Talk:Screw

Types of screw drives section

A note to this article-there's also a rare type of screwdrive (for a reason), whose shape is a triangle. it's called triangle recess, or TP3. 15:03, 28 January 2009 (UTC) —Preceding unsigned comment added by 212.150.245.250 (talk)

There is also a 12-point drive. Commonly used on 4x4 drive shafts. A 12-point socket/wrench fit them.

Carriage bolt, coach bolt and Brunnian's edits

Brunian has made several edits based at least partially on a particular definition of coach bolt.

I was not able to find an internet site that used the same definition as Brunian for coach bolt. The most similar term for what Brunian seems to have intended was coach screw that is defined in places as equivalent to lag screw (lag bolt). Brunian's definition of coach bolt seemed to be equivalent to lag screw (bolt). Unless a source can be found for Brunian's definition of coach bolt his edits with regard to coach bolt should either be removed or edited.

Internet search results with regard to the definition of Coach bolt

(coach bolts and carriage bolts are the same)
http://www.buildeazy.com/glossary/bolt.html

Coach/carriage bolts: are round headed bolts with square shoulders that resist rotation when located or driven into place. They can be called coach bolts or carriage bolts depending on which part of the world you live in. The head end of the bolt does not need a washer, but the other end of the bolt (the nut end) usually does.

(uses term coach bolt to describe what is a carriage bolt in the US)
http://www.screwfix.com/prods/33264/Bolts/Coach-Bolts/Threaded-Coach-Bolts-A4-Stainless-Steel-M8-x-80mm-Pack-of-10
http://www.dealclick.co.uk/product/10908590/Unbranded-Zinc-Coach-Bolt-M12-X-90-With-Nut.php

(defines coach bolt as same as carriage bolt in UK)
http://encarta.msn.com/dictionary_1861687848/coach_bolt.html

U.K. Same as carriage bolt

(uses coach bolt as equivalent to carriage bolt, uses coach screw as equivalent to lag screw)
http://www.fastfixdirect.co.uk/code/navigation.asp?fType=Fasteners&MainCategoryID=6
http://www.interiordezine.com/index.cfm/Interior_Design_Fittings_and_Fixtures/Fixings_2

Davefoc (talk) 16:52, 4 May 2009 (UTC)

Agreed - thanks for the research Davefoc. Wizard191 (talk) 18:26, 4 May 2009 (UTC)

I removed the reference to coach bolt from the screw/bolt differentiation section, I changed coach bolt to coach screw in the screw types section and I changed the definition so that it references the lag screw definition. I think this issue is closed unless Brunnian provides documentation for his edits with regard to this. Davefoc (talk) 17:39, 6 May 2009 (UTC)

Changes to the screws and bolts section

I made the changes for the following reasons: The section was overly specific about what a screw and bolt were: a. some bolts don't have heads designed to be driven. b. some screws don't have heads or at least external heads (set screws). c. threaded fasteners can mate with complementary helixes formed in other ways than tapping.

I realize that the section now repeats some of the opening. This seems a bit awkward and perhaps somebody could improve on the way I did it.

Title of the article

Part of the awkwardness is the title of this article. A long time ago I changed the title of the article to Screws and bolts or Screw/bolts. Somebody came through and changed it back without giving a reason. I still think the article should be titled, Screws and bolts. Long before me, this article morphed into an article describing screws and bolts and I don't see why it's not called that. —Preceding unsigned comment added by Davefoc (talk • contribs) 17:06, 6 May 2009 (UTC)

The impetus for the changes was the change made by 205.179.219.242. I think this is what he had in mind with his parenthetical comment. --Davefoc (talk) 17:42, 6 May 2009 (UTC)

I agree the article title should be something like Screws and bolts or Screw/bolt. The latter avoids plurals. Looking through the archives I dont see any resolved discussion on the title so can we change it to Screw/bolt ? - Rod57 (talk) 20:54, 6 September 2012 (UTC)

Self tapping vs. self threading

I left the term, self tapping, in place. Perhaps self threading would be better though. Self tapping is generally applied to screws designed for use with sheet metal and plastic. The machinery's handbook uses the term, self threading for the general class of threaded fasteners that form their own threads as they are driven. Davefoc (talk) 17:35, 6 May 2009 (UTC)

when I worked in manufacturing the standards office made a similar distinction: self tapping as a hardened screw of no particular thread designed for driving into wood or soft metal (sheet metal, lead battery terminals, etc). Self Threading used a defined thread standard, and was frequently shaped like a tap - a short tapered section with a groove to form a cutting edge and then a parallel threaded section without a groove; Self Threaders were only used in metal, and of a suitable thickness to take several threads. The first type was intended not to be removed, the latter was intended for regular removal and refitting, and could be substituted with a standard bolt of the same thread. Air powered tools were invariably used to drive self-threading screws home the first time.

The (separate) wikipedia entry for Self-tapping_screw seems to conflate both types.

It appears that in the USA the term thread cutting screw has been coined for the second type. I've never heard it in the UK or australia (http://boltproducts.thomasnet.com/Category/screws-screw-threads-thread-cutting-screws). It seems a sensible coinage. Brunnian (talk) 10:38, 19 July 2009 (UTC)

Recent delete of this section

I notice that somebody deleted the whole section and the delete was reverted. In some ways the delete makes sense, IMHO. Part of this section could be used as an intro at the top of this article, combined with the part that is there now in some way or just deleted. This especially makes sense if the title of the article was changed to "Screws and bolts". Other parts of this section might get their own title like the issue of left and right handedness and the issues of rolled versus cut threads. That part needs some changes anyway because it is misleading to call rolled threads a recent advance. Davefoc (talk) 21:12, 6 May 2009 (UTC)

Minor edits for clarity. Davefoc (talk) 21:18, 6 May 2009 (UTC)

Anyone that works in Engineering knows there is a distinct difference between a bolt and a screw. For this reason I think that this article needs to be divided in two to reflect most common usage. No equivalence between the two, a Bolt article and a Screw article. Either that or combine the two under fasteners.Numbat01 (talk) 01:13, 9 July 2010 (UTC)

Once you've read the extensive archives of this page (/Archive 1, /Archive 2), you'll see that there's a lot more to this. You may as well say, "Anyone with correct religion knows that the true God is [insert_favorite_God_here]." Wikipedia lists all of the prevalent views, from natural language usage among the general public, to the conflicting prescribed definitions of various engineering and standardization bodies. — ¾-10 02:08, 9 July 2010 (UTC)

One of the bad things about editing Wikipedia is that it severely undermines your certainty on all manner of topics that you thought you understood perfectly well...who invented radio, what nationality Tesla was, etc. etc. - very discouraging. --Wtshymanski (talk) 02:34, 9 July 2010 (UTC)

Meh...I don't think of it as a negative thing, instead I find it fascinating how "history" predicates towards a certain viewpoint and that when you really study a certain aspect of it its not so clear cut. I suppose I just find the other viewpoints interesting to study. Wizard191 (talk) 12:18, 9 July 2010 (UTC)

Types / differentiation sections

I want to combine the "differentiations" section with the "types of screws and bolt" section. The differentiation section is talking about various types of screws and bolts, so it feel natural to me for it to flow into the various types. Plus the types section has and entry for "screw" and "bolt" that references the "differentiations" section. I think it should be pretty easy segue with something like: "In this article we are going to classify screws into two major categories based on...". Let me know what you think. Wizard191 (talk) 00:32, 23 May 2009 (UTC)

There is definitely duplication between the 2 sections currently. But I am having trouble envisioning how to merge them. I would say give it a shot if the inspiration strikes. Could hash it out on a subpage first. — ¾-10 02:37, 24 May 2009 (UTC)

I attempted it in my sandbox and it didn't go very well. It made sense in my head at the time. I think I'm just going to move the "types of screws and bolts" section under the "differentiation" section. Wizard191 (talk) 12:37, 25 May 2009 (UTC)

change to "Other distinctions" part of the "Differentiation between bolt and screw" section

The citation was removed and a hidden note was added to the source. The note, by wizard191, says that he doubts that the alternative definition for bolt and screw listed in the link exists.

I disagree a bit. Keithonearth believed that this was the distinction in the long discussions about that section. I suspect other people have arrived at a similar idea. It might be the most rational way to define the terms. I used the reference to prove that there is some support for this distinction. The section goes on to explain that the distinction is not one that is consistent with general use or formal specification. I suspect that this may be the only reference to such a distinction on the internet, but given my general sense that at least some people believe that it is correct I thought it was reasonable to discuss it in the article. As such, I thought the section was useful as it stood and didn't need to be changed. --Davefoc (talk) 13:56, 25 May 2009 (UTC)

What I meant was that I don't think there's an online reference for that definition, but if a source can be found else where I have no problem including the info in the article. I couldn't let the previous reference stand because it wasn't a reliable source. Unfortunately, if a source can't be found it will have to be removed per wp:v. Wizard191 (talk) 18:02, 25 May 2009 (UTC)

We had this discussion long ago. I was concerned about the use of a questionable source and you suggested that I shouldn't use it. In general, I suspect we have similar ideas about what a reliable source is and for most purposes this kind of source would certainly not qualify as reliable. However, in this case, this source provides a reliable data point that at least somebody holds this view. Some credibility to the idea that these kind of definitions of screw and bolt exist beyond the existence of the data from this web site is that Keithonearth argued strongly for a similar definition. For me the issue is whether the view is held widely enough to justify addressing it in this Wikipedia article. I don't know the answer to that. It seems like a logical view that some people are going to come to on their own and it is reasonable to address it just for that reason, but I don't have a strong feeling about this and maybe the idea is just too obscure to be worth addressing in this article. --Davefoc (talk) 20:51, 25 May 2009 (UTC)

I put back the citation that was objected to. This kind of citation for this kind of thing seems to be addressed in the link to reliable sources that Wizard191 provided. I also made some minor changes to the screws are small and bolts are big addition to this section. It is difficult if not impossible to provide formal documentation for either idea because nothing formally defines screws and bolts in this way. But these definitions were not presented as formal definitions. They are in the article to discuss the ways that on occasion the terms are used informally.

It is possible that the entire Other distinctions section should be deleted. Certainly if there is a requirement that formal documentation be found for informal usage of the terms screw and bolt that may be necessary. But even without that perhaps this section doesn't add sufficient value to be retained.--Davefoc (talk) 15:37, 2 June 2009 (UTC)

I posted the source in question to the RS notice board, which is found here: Wikipedia:Reliable sources/Noticeboard#Screw source. According to the reply I've removed the reference. Wizard191 (talk) 22:34, 6 June 2009 (UTC)

With respect, I think you have not understood my point. The other distinctions part of this section deals with ideas about the distinction that are not formally excepted distinctions but do have some usage. Formal sources are not likely to be available for usage which might be common but which is not formally supported. If this kind of source is not acceptable to document an informal usage then consideration should be given to removing the entire other distinctions part of this section since it will likely not be possible to provide any citations for it. Also with respect, when you posted the issue about reliable sources you failed to present anything representative of what I had to say about the issue. Perhaps most importantly, that I realized for most purposes the use of this kind of source was clearly unacceptable but that in the very limited case of what it was being used for here it might be acceptable. In the article that you linked to this kind of use for this kind of source seemed to be acceptable for exactly the kind of purpose it was used for here. Davefoc (talk) 13:58, 7 June 2009 (UTC)

If a source can't be found for that section then it should be deleted per WP:V, which states "The threshold for inclusion in Wikipedia is verifiability, not truth". If the information cannot be verified then it cannot be included. I understand that you are just trying to show that other viewpoints exist, but these other viewpoints still have to have a solid foundation. We can't include an entry that says "a screw is any fastener longer than 1 foot and a bolt is anything shorter than 1 foot", just because someone stated it on their tripod website. I realize that the statement in question seems much more plausible, but that doesn't mean it doesn't need to meet the usual reliable sources guidelines. (P.S. In the noticeboard request I gave a link to this talk page, but wasn't going to rehash everything discussed, because there was just too much.) Wizard191 (talk) 22:37, 7 June 2009 (UTC)

Your points are reasonable Wizard191. Although I think this is a gray area that is not as clear cut as you do. An article about prominent urban myths might reasonably enough link to a site that promoted the idea that Elvis Presley was alive. This is a similar case in that the section is about an idea that is prominent enough that Keithonearth argued for it and that I suspect many people believe. What I was never sure of was whether the view was prominent enough to justify mention, however it is a view that I suspect many people come to at some point that have thought about exactly what the two terms mean. Having said that, I think whatever you do with regard to this will be fine.

Davefoc (talk) 05:30, 8 June 2009 (UTC)

I fear that the difference between a bolt and a screw may not be defineable. The definition of being able to receive a nut for bolt seems good, but I remember buying machine screws for work that fit the definition of bolt. Perhaps bolts are a subset of screws. Usage may be arbitrary as in motor/engine. --Weetoddid (talk) 22:49, 6 June 2009 (UTC)

I've added back the "alternative" definition and the link to the Structural Analysis Reference Library. It has every appearance of being a sensible reference work, and the superior usefulness and logic of the definition should tip the balance of any debate in favour of inclusion. There is obviously no descriptive definition for either term that will fit every fastener that has ever been called a screw or a bolt. The ambiguity of the terms is a vicious circle - people called a "machine screw" a screw because an ambiguity existed, and now the ambiguity is entrenched. The "alternative" definition most certainly is not descriptive, in the sense that it doesn't describe how everyone uses the two terms. But it serves as the most useful prescriptive definition - suggesting how the terms should (or at least could) sensibly be used. —Preceding unsigned comment added by Michael S G 82.152.203.195 (talk) 02:03, 12 May 2010 (UTC)

Please re-read the above, the problem is not if it makes sense, its that the source is not reliable per WP:RS. Also, please review WP:V. Wizard191 (talk) 13:30, 12 May 2010 (UTC)

ASME B18.2.1

The nominal thread length, for reference and calculation purposes, for bolts is as follows:

   If the bolt length less than or equal to 6", the nominal thread length is calculated as (Diameter X 2) + 0.25.
   If the bolt length is greater than 6", the nominal thread length is calculated as (Diameter x 2) + 0.50.

Note: Thread lengths specified above are the minimum required thread lengths to be supplied if a thread length is not specified.

Bolts have one smooth diameter which fits closely in the hole to prevent fatigue and are torqued to plasticity to stop vibration causing fatigue cracking, two diameters plus of thread length is for one nut and a lock nut. Anything threaded the entire or nearly the entire length is a screw, tapered or not. This means some short bolts could be called screws, but look at the thickness of the shank. A good bolt MUST have a washer to support the nut because the thread top is level with the shank, nuts would grind into the surface metal. The same applies to coach bolts (putting a washer under the head defeats the purpose of the head, and omitting the large washers means the nut just pulls into the wood) Lag bolts are a slight variant but the same principle, the (usually)screw end replaces the threaded end to both put tension in the bolt and open the lag shields to anchor them in the concrete. The not-threaded /not-screw length can of course be any length. Machine screws are just that, essentially fully threaded constant diameter fasteners, not intended to be used with nuts but threaded holes. Spaghettij (talk) 16:27, 8 April 2013 (UTC)

Explanation for reversion of good-faith EL change

One would think that the info would be "surely available through noncommercial sites", but I have actually looked into that and found that the best info on fasteners and tools tends to come from supply houses. I deduced that the reason for this is that the only people with the time and money to make these really great information resources (ie, thousands of pages of brief descriptions with great photos) are the ones whose livelihoods are tied to it. For example, the MSC, McMaster-Carr, and Enco catalogs are collections of information (especially the photos) that would be excellent to have for Wikicommons, but of course it cost them a lot of money to amass this resource and they only give it away to the extent that it leads people to buy from them, which is entirely understandable. Eventually we can get GFDL photos of every type of fastener and tool in the world, but it takes time, which equals money. Here's a toast to continuous improvement and pro bono moonlighting. — ¾-10 23:25, 29 May 2009 (UTC)

I had a discussion with the reverting editor on his talk page and am in the process of trying to add the info to the article. I've just uploaded SVG versions of the head marking and just need to start on the table. But I have to agree with you that there's a lot of real good info out there at commercial websites (especially McMaster). I know I personally use it on a daily basis for design information at work. Wizard191 (talk) 23:43, 29 May 2009 (UTC)

What to do with bolted joint?

So I've been working on some of the mechanics of this article, but the sections still need a lot more work. Right now I'm apprehensive to make more drastic changes, because of the bolted joint article, which has some good information, but overlaps some of its content with this article. For instance, both articles have info on bolt strength, proper torquing, and property classes. Now I realize there's going to be a slight overlap on some information, but I think we need to figure out properly split the information. Right now this article is 70 kB, so it's pretty big, but I suppose one option is merging bolted joint into this article. However, right now I'm leaning more on taking the strictly screw information, like property class information, and moving that from bolted joint into this article, and then taking the information about torquing, etc., and moving that to bolted joint. However, I'm definitely open to other ideas. Wizard191 (talk) 01:02, 10 June 2009 (UTC)

129.97.36.75 's edits about computer controlled torquing

The revisions in question are these:
Wizard191 version:

Large volume users such as auto makers frequently use computer controlled nut drivers. With such machines the computer in effect plots a graph of the torque exerted. Once the torque ceases to rise (the point where the bolt begins to deform) the machine stops. Such machines are often used to fit wheelnuts and will normally tighten all the wheel nuts simultaneously.

129.97.36.75's version:

Large volume users such as auto makers frequently use computer controlled nut drivers. With such machines the computer in effect plots a graph of the torque exerted. Once the torque reaches a set maximum torque chosen by the designer, the machine stops. Such machines are often used to fit wheelnuts and will normally tighten all the wheel nuts simultaneously

I believe that two different ideas have been confounded here. The use of computer controlled tightening machines to achieve the optimal torque by tightening until there is a drop in torque and the use of computer controlled tightening machines to automatically achieve a particular preset torque.

I suspect that lug bolts are torqued until a specific torque is reached and are not torqued to achieve the optimal torque for resistance to unwanted resistance to loosening. I am not sure though and neither editor has provided a citation for their edit.

I believe that some head bolts are torqued using the procedure that Wizard191 mentioned since there are some head bolts which are designed to be used only once.

Either way it seems like the paragraph as it now stands has problems because of a lack of citations and the possible confounding of concepts.
--Davefoc (talk) 20:58, 16 June 2009 (UTC)

FWIW, I didn't write that paragraph, however I believe you are right DaveFoc. There are two different concepts/procedures being described and they are both probably right. As such, they should both be described. But I think a source needs to be found for each concept first. Wizard191 (talk) 21:38, 16 June 2009 (UTC)

Unified thread standard

I'm having huge difficulty believing 'At least 85% of the world's fasteners are dimensioned to Unified thread dimensions'. It is certainly contrary to my experience, where ISO metric threads seem to dominate. I've tried to buy UNC fasteners on every continent to repair US made machines, and rarely succeeded immediately outside the USA. Even Canada seems to use more Metric than Unified threads. Brunnian (talk) 14:13, 15 July 2009 (UTC)

You are quite right. There's no such source as "The World Fastener Review". I think it's some really old sneaky vandalism. Wizard191 (talk) 14:45, 15 July 2009 (UTC)

Check with the Industrial Fastener Institute (IFI), a very real organization. Joe Greenslade is the director. —Preceding unsigned comment added by 72.72.20.207 (talk) 17:43, 20 January 2010 (UTC)

Triangular slot?

I've seen screws with a triangular slot, similar to the Robertson head but having an equilateral triangular depression instead of a square hole. I've seen it primarily used in plastic kid's toys, e.g., the kind you get with a McDonald's Happy Meal. Any idea what this head type (or driver type) is called? — Loadmaster (talk) 17:56, 17 July 2009 (UTC)

See top of this talk page. Ortolan88 (talk) 15:33, 19 July 2009 (UTC)

Acme Thread

What about the Acme thread, a trapezoidal thread from used for feedscrews, high-torque and self-braking mechanisms? Does it deserve a bit more detail than being stuck with the obsolete threads? —Preceding unsigned comment added by Brunnian (talk • contribs) 21:22, 8 August 2009 (UTC)

Really there needs to be a small topical section created for leadscrews thread forms, which contains the acme thread form. Wizard191 (talk) 22:57, 9 August 2009 (UTC)

Acme thread are hardly obsolete. They are commonly found on bench vises and heavy-duty C-clamps.

What does shank mean?

From the opening section:

Some screws have an unthreaded portion of the shaft under the head, which is known as the shank.

In every other place the word shank is use it sounds like it means shaft. For instance:

Fasteners with a non-tapered shank are designed to mate with a nut or to be driven into a tapped hole.

The word shaft was replaced with the word shank throughout the article. That seemed to make sense if shank means shaft with regards to screws. Shank seems like a more specialized fastener type word. But if shank actually means the unthreaded part of the shaft then consideration might be given to modifying at least some of the sentences that use it to mean the whole shaft.

The nail article defines shank as:

the body the length of the nail between the head and the point; may be smooth, or may have rings or spirals for greater holding power

It seems like shank=shaft when it comes to screws. I would like to have confirmed that with a dictionary definition but the definitions I saw didn't cover this issue, at least not unambiguously. What is the source for the definition of shank provided in the opening paragraph? --Davefoc (talk) 10:19, 18 September 2009 (UTC)

Hey Dave, good to see you back again. I was the one who made the change from "shaft" to "shank". The source for the text in the intro came from: [1]. In my mind I think of the terms shaft and shank interchangeably, but I think you make a good point above. Whenever the text is referring to the body under the screw threads I think it makes sense to call that the "shaft". I would be willing to change those instances back to "shaft". Wizard191 (talk) 14:34, 18 September 2009 (UTC)

Hi Wizard191, from page 39 of your source:

D. Shank-the cylindrical part of a bolt that extends from the underside of the head to the point.

The drawing above that text ambiguously points to the unthreaded part of the bolt as the shank, but that may not mean that the entire shaft of the bolt isn't the shank. The text seems to make it clear that the entire shaft of the bolt is the shank. This suggests to me that the opening paragraph is wrong when it states otherwise. Davefoc (talk) 15:56, 18 September 2009 (UTC)

Hrm, you are quite right. I just based the text in the opening paragraph on the photo and never realized there was text that went with it. I will updated the opening paragraph to reflect this. Thanks for you diligence. Wizard191 (talk) 16:31, 18 September 2009 (UTC)

Good job. I think this issue is closed.

I cannot recall ever seeing 'shaft' used in this manner; 'shank' is the right term. —Preceding unsigned comment added by 72.72.20.207 (talk) 17:43, 20 January 2010 (UTC)

Darysys October 4, 2009 edits

Darsys, made a number of edits to the Fasteners with a tapered shank (self-threading screws) section: They provided interesting information, however I believe there are some issues with his edits.

(Teks® screw)

I thought adding the ® was a good edit and a reasonable thing to do, so much so that when I put that item in the list I included it originally. Somebody came through and took it out without comment. I didn't know why. I thought if somebody thinks it should be removed again, they might stop by and explain why before they delete it again.

Wizard191 deleted the trademark symbol. He said that it violated Wikipedia standards to use it. He seems to be right: MOS:TRADEMARKS--Davefoc (talk) 08:58, 4 October 2009 (UTC)

Addition of size information about Teks screws

I thought this was useful information and probably should be retained. However these are not the bad old days of this article (of which I was a participant) when unsourced material was just added willy nilly. At least for new material, sources should be supplied otherwise we are going fall farther behind on proper sourcing for this article.

Asymmetrical threads on particle board screws

I didn't know that particle board screws have asymmetrical threads and that is interesting, but I don't know what asymmetrical threads are. Perhaps a reference to where that is explained would be helpful. And the no source comment applies to this item also.

If you look at cross-section of an individual thread, it is often in the shape of an upside-down V with both sides symmetrical about an imaginary axis that runs from the tip of the thread to the bottom of the profile, like an isosceles triangle. Asymmetrical threads have been optimized for the material the screw is designed for. The cross-section of the threads are not symmetrical: one side is steeper than the other. This configuration may be to reduce installation torque or to maximize the pullout force required to rip the fastener out of the material (as opposed to unscrewing it). —Preceding unsigned comment added by 72.72.20.207 (talk) 17:43, 20 January 2010 (UTC)

Auger tip for decks screws

Again good information. This is difficult to source because it includes a conclusion that most deck screws have this kind of tip. I'd settle for a couple of cites of prominent manufacturers of deck screws that have auger tips. Also, some link to a place where auger tips are described would be helpful. —Preceding unsigned comment added by Davefoc (talk • contribs) 02:40, 4 October 2009 (UTC)

Auger point, also called Type 17 point, are indeed common in deck screws because they do not require predrilling. I don't think they are universal as there may be some other proprietary designs, but I can say that the auger point is the one feature that distinguishes deck screws from 'standard' flat-head wood screws (other than the corrosion-resistant coating). Note that there are many other screws that have an auger point. —Preceding unsigned comment added by 72.72.20.207 (talk) 17:43, 20 January 2010 (UTC)

205.243.112.50 's edit to bolt/screw distinction section

205.243.112.50 changed the opening section so as to directly quote ASME B18.12 as to what the difference between a screw and a bolt is. The previous version quoted the distinction listed in the Machinery's handbook which I believe was derived from ASME B18.12. That seems to be an improvement in that a primary instead of a secondary source is quoted.

However I reverted his change overall, because:

1. The wording might be improved
2. It includes the comment that "This definition is distinctly different from that of a screw". I think this is obvious. The difficulty is that the definitions are not mutually exclusive. Some things can be both a screw and a bolt as per the definition. And in common usage some things that are usually referred to as bolts are actually screws based on the ASME B18.12 distinction.
3. It fails to provide a lead in to the section that follows that discusses in detail some of the issues associated with the distinction of bolts and screws.

I thought that ideas as to possible changes to the section had some merit. Perhaps the paragraph should start out with the ASME B18.12 distinction. It should then follow that up with a sentence that explains that not all fasteners can be unambiguously determined to be a bolt or a screw using the ASME B18.12 distinction.Davefoc (talk) 05:35, 13 October 2009 (UTC)

I agree with the reversion. By all means, I support good-faith contribution, but looking at 205.243.112.50's edit diff, my first reaction was, essentially, what Davefoc said regarding "fails to provide...". This is just one of those parts of Wikipedia where you really need to read closely everything that's currently there before attempting to improve it, because the amount of exhaustive analysis already poured into it was very large. Best to all, — ¾-10 02:48, 14 October 2009 (UTC)

Reverting this change was a mistake. The language maybe should have been cleaned up but this edit actually provided the real, verifiable, source appropriate definition of the differences between a screw and a bolt. There are standards organizations throughout the world that are composed of industry experts. ANSI is the nationially accepted standards organziation in the USA. They are the definitive authority on such things as fastener standardization. ANSI, simplistically, farms the standardization of fasteners out to ASME. ASME is the clear authority when it comes to defining the difference between bolts and screws. All relative fastener organizations (ASME B18, ASTM F16, ISO TC/2, etc...) agree on the ASME B18.12 definition. There is not a single reference in any fastener technical publication anywhere to Machinery's Handbook. It is not an authority on the subject and is frequently representative of out of date information. I am willing to clean this up if it isn't going to be changed right back to inferior references like the Machinery's Handbook. (chwillia1) — Preceding unsigned comment added by Chwillia1 (talk • contribs) 21:56, 28 November 2012 (UTC)

In general, I oppose the removal of material solely because it is "obvious" -- see WP:OBVIOUS. I also even more strongly oppose deleting references to relevant standards organizations because of writing issues such as "The wording might be improved" or "It fails to provide a lead in". Such writing issues are relatively easy to fix once the information is in the article. All too many Wikipedia articles lack good references -- which seems to indicate that a lack of references is relatively difficult to fix. --DavidCary (talk) 01:56, 21 July 2013 (UTC)

"locate objects"?

All that comes to mind is a metal detector or something. That part should be rewritten. -Craig Pemberton 09:52, 12 November 2009 (UTC)

I think the poster is referring to this sentence in the first paragraph: "Their most common use is to hold objects together or locate objects." I agree with the comment.

It is not clear to me what locate objects is meant to mean.--Davefoc (talk) 16:09, 12 November 2009 (UTC)

Does this help: [2]? Wizard191 (talk) 17:47, 12 November 2009 (UTC)

Yes it's better and I thought that was what you meant. But I'm not sure it's useful to have "position objects" in the sentence at all. The distinction between holding objects together and fixing an object into position seems very subtle to me. One can attach a picture to the wall using screws or one can position a picture on the wall using screws. It seems like it's just two different ways of saying the same thing. Maybe I still don't get what you mean by position objects.--Davefoc (talk) 18:30, 12 November 2009 (UTC)

I'm really referring to things like jack screws, where the screw is used to set a position but it doesn't actually anchor anything. Wizard191 (talk) 18:40, 12 November 2009 (UTC)

maximal diameter?

The sizing section says: "The numbering system follows a roughly logarithmic series where an increase in each screw number size approximately doubles the tensile strength of the screw and the screw number is found by $d=.060''+(\#\times .013'')$, where "d" is the nominal diameter." However, I suspect that maximal diameter is meant instead of nominal? —Preceding unsigned comment added by 64.105.21.209 (talk) 04:06, 16 December 2009 (UTC)

Thanks for the heads up. I've fixed it in the Unified Thread Standard as I'm going to trim up the section here. Wizard191 (talk) 15:35, 16 December 2009 (UTC)

One-way and Clutch are NOT the same, not even close

I am surprised to see this kind of error on Wikipedia, shown on the screw profiles at the right edge of the article. A one-way screw is as illustrated, a modified slotted recess with ramped edges that prevent removal without a special tool. It is a type of security or tamper-resistant/tamper-proof fastener. A clutch recess, sometimes called a butterfly screw, comes in two basic styles, A and G. Both are 'traditional' recesses in that they are symmetrically formed into the head; installation and removal are equally easy. It is uncommon but not really considered a security fastener. —Preceding unsigned comment added by 72.72.20.207 (talk) 17:43, 20 January 2010 (UTC)

Quite right; I've corrected the template. Wizard191 (talk) 18:42, 20 January 2010 (UTC)

That very topic had been bugging me for a while, but I couldn't decide how to address it, because I couldn't think of how to differentiate one-way from clutch within the constraints of the B&W (i.e., nongrayscale) stylized drawings, which is the illustration style used throughout that template. I had visions of a vector graphic with a gradient screen to stylistically represent the sloping contours of the one-way head (not sure if I described that very well—I know what I mean!), but my Adobe Illustrator skills are still too remedial to execute such a slick idea. Anyways, there's always tomorrow … — ¾-10 00:40, 22 January 2010 (UTC)

Flange bolts?

No mention is made of flange bolts in this article. This would be helpful information. Wakablogger2 (talk) 01:07, 1 March 2010 (UTC)

I've added a section about flanged heads. Thanks for the heads up. Wizard191 (talk) 16:15, 1 March 2010 (UTC)

Wow, very nice. Thank you :) Wakablogger2 (talk) 02:06, 2 March 2010 (UTC)

Taptite screws

User 86.181.159.85 added a description of Taptite screws to the "Fasteners with a tapered shank (self-threading screws)" section.

Taptite seems to be a particular brand of screws. Perhaps there is common usage of the word, taptite for a particular kind of screw, but based on a review of the company's web site it looks like they make a range of screws and the use of the word taptite for a particular kind of screw may not be appropriate here.

There is already an entry for "thread rolling screws" in the "Other threaded fasteners" section. The term, thread rolling screws, may be the generic name for the screws that were described by 86.181.159.85 as taptite. Perhaps the "thread rolling screws" entry should be moved to the "Fasteners with a tapered shank (self-threading screws)" section? The text for the section might be derived from the existing "thread rolling screws" text and the text created by 86.181.159.85.--Davefoc (talk) 18:01, 10 April 2010 (UTC)

Agreed. I've removed the taptite section and moved the thread rolling section up. Wizard191 (talk) 16:55, 13 April 2010 (UTC)

spanner head

Should be renamed to "snake eye" or "pin head", spanner implys a hexagon or square head. Try a google search for a "pin spanner" —Preceding unsigned comment added by 92.30.36.125 (talk) 20:15, 14 May 2010 (UTC)

The Wikipedia policy for inclusion is a reliable source; a google search is not a reliable source. If you can find a reliable source then feel free to add the other names in addition to "spanner". Wizard191 (talk) 21:30, 14 May 2010 (UTC)

Where to place info on gauge diameter?

I found this technical info on the equivalent mm diameter of various gauge sizes for self-tapping screws and wanted to add it to this article, but I'm not sure where to place it:

Gauge number	0	2	4	6	8	10	12	14
Approximate diameter (mm)	1.5	2.2	2.9	3.5	4.2	4.8	5.5	6.3

Source: [3]

There is also more valuable info on this site, such as

1. Metric-Imperial conversion table → could go to "ISO metric screw thread"
2. Metric Thread Pitch and Tapping Drill Table → could go to "ISO metric screw thread"
3. Imperial thread pitch table → could go to "Unified Thread Standard"

Let me know what you think. invenio tc 12:23, 1 June 2010 (UTC)

We already have all that info in the following articles: Unified Thread Standard, List of decimal-fraction equivalents: 0 to 1 by 64ths, and ISO metric screw thread. Wizard191 (talk) 15:41, 1 June 2010 (UTC)

Deleted link

"This link does not provide any additional information (reason for deletion)," but that is not the sole criteria for external links. Wikipedia users do not want to sift through hours of information to receive the basics. There are many people who have used this link efficiently, which I know through 4Q survey information. This is a solid link that contributes to the wikipedia page by highlighting the most desired and important information in a short span. This creates a unique resource that is efficient and palpable for users. I will not put the link back up again myself, but I sincerely believe that the link should be reinstated due to the reasoning given above.

Thanks for your time, 12.170.211.135 (talk) 18:14, 5 July 2010 (UTC)Dane Lawless

The preceding is the message I posted to the current main editor of the "screw" page here on wikipedia (message slightly modified since). I was told to bring the issue of the deleted external link up on the screw talk page. So, I am not sure if I need to attempt to gain popular support here for reinstating the link or simply bring the issue up and hope the powers that be reinstate it. The external link had been listed for close to a year and was beneficial to many. I am perplexed that one respected editor does not agree with my assessment. Thanks for everyone's time in reading and considering this issue.

98.115.66.194 (talk)Dane Lawless

Here are the Wiki guidelines which support the reinstatement of deleted EL: www.hingedummy.info/screwinfopage2.htm Writing in brackets below has been added.

What to Link

There are several things that should be considered when adding an external link.

• Is the site content accessible to the reader? [Yes]
• Is the site content proper in the context of the article (useful, tasteful, informative, factual, etc.)? [Yes]
• Is the link functional and likely to remain functional? [Yes] —Preceding unsigned comment added by 98.115.66.194 (talk) 17:51, 8 July 2010 (UTC)

I contend point 2: I don't think the link is useful. All of the info is already present. You also forgot to judge the link by: "Each link should be considered on its merits, using the following guidelines. As the number of external links in an article grows longer, assessment should become stricter. When in doubt about the appropriateness of adding new links, make a suggestion on the article's talkpage and discuss with other editors." The amount of links that were here before, as enormous, so I cleaned house, and only left those which are still useful. This article has grown a lot since your link was here. Also, your link doesn't qualify for any of the points at WP:ELYES or WP:ELMAYBE. As such, the link should not be re-added. Wizard191 (talk) 19:29, 8 July 2010 (UTC)

I looked at the proposed link and I agree that it contains nothing that can't be duplicated here, or is not already here. Plus it's a web site selling screws, so it's spam. --Wtshymanski (talk) 02:34, 9 July 2010 (UTC)

TO WTSHYMANSKI: It is far from a website selling screws. It has one advertisement on the side bar of the page. You cannot buy screws from this website, nor does it sell anything else. If you consider spam any website with one advertisement on it, you would not be able to link to the majority of the web. Your statement is completely false, with the only shred of truth based on the fact that there is a small square single ad in the corner of a content filled page. —Preceding unsigned comment added by 98.115.66.194 (talk) 13:53, 9 July 2010 (UTC)

TO WIZARD191: You have been responsive and professional. I contend that the link does qualify with all of the above including WP:ELYES and WP:ELMAYBE due to the bold reasoning given above. However, I concede that I am in the minority and this will be my last post on the matter. Thank you.

TO WIZARD191: I was hoping my last post was the end of the matter. However, Wtshymanski has also removed my www.hingedummy.info link off of the wikipedia hinge page. This is due to me posting on his talk page with a complaint. He has a personal vendetta against me. The link on the hinge page is completely legitimate and it is nonsense to argue otherwise. The entire site is dedicated to hinges and provides a wealth of information that is not present on the page. The site has installation instructions for several different types, descriptions of hinge types, hinge anatomy illustrations, hinge glossary, hinge faq's, hinge history, hinge finishes listings, door and hinge removal instructions, etc. No site has even close to this kind of comprehensive coverage of the hinge. Please talk some sense into him. This is not professional wikipedia editor behavior. I have been nothing but professional and have followed wikipedia guidelines for suggesting an external link be included. Wtshymanski has taken to name calling and pettiness in this otherwise professional debate. —Preceding unsigned comment added by 98.115.66.194 (talk) 14:18, 9 July 2010 (UTC)

I'm sorry you feel there's a vendetta against you; for it to be personal, I'd have to associate edits with a person. I do edits, not vendettas. Please read Wikipedia:External links. We don't link websites because they are good websites, we link websites as a poor substitute for putting data into the article or for linking to materials that otherwise can't be cleared to use on Wikipedia. Parts catalogs are in my opinion generally not good links for an encyclopedia. --Wtshymanski (talk) 16:29, 9 July 2010 (UTC)

The website is not a parts catalog. You are not being truthful. I just listed the websites attributes in the last post. This is clearly a vendetta against me otherwise you would not have gone out of your way to delete the other external link. Please do not insult my intelligence and the rest of the Wiki communities'. The website surpasses all qualifications and should be included on the hinge page. And the website would be considered a "poor substitute" for not putting data in the article, as there is very little in the hinge article. I would like others to comment on this issue. —Preceding unsigned comment added by 98.115.66.194 (talk) 18:56, 9 July 2010 (UTC)

Keep out per WP:ELNO#1 - the information is redundant.

Keep out per WP:SPAM - the site is a promotional vehicle for a hardware store and was added against a WP:COI.

The burden is on the editor wishing to include the link. Best to give a very WP:CIVIL argument if you want you perspective to be considered.

Looks like sockpuppetry going on as well. --Ronz (talk) 20:40, 9 July 2010 (UTC)

I am the one being civil. I was called a link spammer and have been outright lied to a couple of times. How can I be a link spammer when I have only added one link to the screw page, and when it was removed I just requested that it be reinstated? I am trying to make an intelligent arguement. Will someone join me please? Sockpuppetry? I am not sure what you even mean by that. And I did not add the link on the hinge page, it was removed after I complained about the screw page link (which I did add) being removed. And if I was COI, that does not mean I cannot edit at all. I have not even done any editing, I am just requesting that someone elses editing be undone because it was a personal attack. —Preceding unsigned comment added by 98.115.66.194 (talk) 21:00, 9 July 2010 (UTC)

Responded on your talk page. Sorry I hadn't notified you prior. --Ronz (talk) 21:08, 9 July 2010 (UTC)

Yes, you should avoid or exercise great caution, not that you cannot comment at all upon certain edits. The link deleted was clearly a personal attack, by Wtshymanksi, when you look at the screw talk page. The link on the hinge page exceeds all expectations of a wikipedia link, and was believed to be a sufficient link by many other wikipedia editors for over a year. I believe Wtshymanski, now has a personal issue or COI in this dispute and his editing should be undone. —Preceding unsigned comment added by 98.115.66.194 (talk) 19:19, 12 July 2010 (UTC)

Ronz is right, it's a promotional site for a hardware store. It shouldn't be linked anywhere unless we had an article on the Lawless family. Dougweller (talk) 20:24, 12 July 2010 (UTC)

It's borderline. However, seeing how the site has had spam issues in the past and there is consensus above, I believe it is best to leave the site out of the article. I'm sure there are plenty of other better sites out there. Wizard191 (talk) 02:01, 13 July 2010 (UTC)

All this shows is that some Wiki editors are more concerned about "spam" than they are their readers (or "winning" a debate). Hingedummy is the most informative site about hinges on the entire internet! The Wiki community is better benefited as a whole including the hingedummy link, but you guys are so concerned about "spam" that you blindly ignore an objective look at the issue. Show me a better link, that is not a book, and I will concede. I would even contend that a book would not be better, as it is cumbersome to find the desired information.

Look at the EL's for the "chair" page on Wiki. This is outrageous. Can I delete the "chair" page links and then make them prove their worth? They have Google Ads featured on them so I'd say its "spam." According to these standards, I could delete almost every Wiki EL and they would never be reinstated. On a side note, the expansive use of the word "spam" here is quite entertaining.

Thanks for responding Wizard. I must inform you though that there is not a better site about hinges than hingedummy. This is just a simple statement of fact, no hyperbole. I believe you have been crippled by your peers, but I understand your reasoning. —Preceding unsigned comment added by 98.115.66.194 (talk) 16:58, 13 July 2010 (UTC)

So, anyone want to explain the "chair" page links to me? Policy must be consistent here at Wikipedia. Please explain why the "chair" page links are considered OK, but the hingedummy link on the hinge page is not. —Preceding unsigned comment added by 98.115.66.194 (talk) 16:45, 15 July 2010 (UTC)

There are loads of bad articles, bad links, etc. That's no excuse to sink to the least common denominator. No editor has any responsbility to do anything about another article because you are unhappy. Dougweller (talk) 18:41, 15 July 2010 (UTC)

I would not associate the most apropos site concerning hinges on the entire internet with the least common denominators on the "chair" page, but I digress. I guess I will help you guys out then and begin enforcing your EL policies. —Preceding unsigned comment added by 98.115.66.194 (talk) 19:15, 15 July 2010 (UTC)

wizard191 Vincent Yotti-concrete screw

please explain your revert. —Preceding unsigned comment added by Kilbert (talk • contribs) 20:28, 7 September 2010 (UTC)

"rmv dubious claim to an inventor using a primary reference; I couldn't find anything on the internet that supported the statement". Wizard191 (talk) 20:41, 7 September 2010 (UTC)

History (2010 discussion thread)

If the screw was described by Archytas of Tarentum (428 – 350 BC), it cannot have been invented by Archimedes (c. 287 BC – c. 212 BC). Engelsman (talk) 18:16, 14 October 2010 (UTC)

I marked the two sentences with dubious tags. Wizard191 (talk) 15:53, 31 December 2010 (UTC)

The 15th century is in Rybczynski. David R. Ingham (talk) 06:02, 15 March 2012 (UTC)

Types section

What does everyone think of converting the types of screws section into a table format, like the one at wrench, so that images can be included with the descriptions? I think its a cleaner layout as well. Wizard191 (talk) 16:05, 31 December 2010 (UTC)

Support. I think that's an awesome idea. I may be slightly biased, but that's my two cents. — ¾-10 18:08, 31 December 2010 (UTC)

I'd like to incorporate my changes. Peter Horn User talk 15:44, 16 February 2011 (UTC)

Well I finally had time to finish this off. Some notes I'd like to bring up from doing this:

• I removed the "stud" entry, because I don't *think* a stud is a screw, however I'm not 100% sure. That's why I'm bringing it up here. The current threaded rod article, which also covers studs, doesn't refer to the fastener as a screw, which is why I removed it. Please advise if you don't think this is the best course. Also, there's still an entry for "Double ended screw"/"dowel screw" which is really a stud, so what should we do with this?
• I also left out "thumb screw" because I think it's a screw drive, and ought to be listed there. Opinions? Wizard191 (talk) 20:08, 8 April 2011 (UTC)

These tweaks sound fine to me. As Wizard apparently already knows (explaining here for anyone else who wonders), a thumb screw is one of those screws with a head easily gripped by the human fingers, such that you can drive it with your fingers—the male homologue to the female wingnut. IMHO whether one discusses it in this article or in the drive types article has to be an arbitrary coin-toss, so I'm fine either way. Same with studs. They're a threaded fastener, but if this article is implicitly only about threaded fasteners that aren't driveless, then I suppose that studs should only be mentioned here in a see-also, in-passing kind of way. Makes sense. Interestingly, the distinction is "driveless", not "headless". Many types of set screws are classed as headless (no head that sticks out past the threads), but they're not driveless, because they have drives such as slots or hex sockets. — ¾-10 16:46, 9 April 2011 (UTC)

P.S. Nice tables. — ¾-10 16:51, 9 April 2011 (UTC)

The definitions under Cap Screw are incorrect (albeit very minor): "A socket cap screw, also known as a socket head capscrew, socket screw, "set screw" or Allen bolt, is a type of cap screw with a cylindrical head and hexagonal drive hole."

a set screw, as defined further in the same table, has no head. Any screw with 'cap' in the title is by this definition headed ("with a cylindrical head") therefore a set screw by virtue of being headless cannot be a cap screw. Ken (talk) 14:31, 13 August 2014 (UTC)

Coatings

Six different tanks for blackening? I only counted 4.

The discussion is oversimplified as it does not deal with typical protective coating processes such as anodizing for aluminum; ozide treatments for brass; passivation for stainless steels; conversion coatings (phosphate and oil), or mechanical plating, or galvanizing and electroplating of zinc, cadmium, nickel, and copper-nickel-chrome for steels.

Picture

Also, the picture of the Carriage Bolt is labeled in error; the square shank is directly below the bolthead, then there is a round, unthreaded shank, followed by the threaded section. Acey-Deucy 16:57, 28 December 2006 (UTC)

The bolt picture is valid as there are several types of bolts, each of which have several types of geometrical features present along there shank. This picture could be said to be one of the more general cases which features the commonly found features on a bolt.

The text also seems to be missing the information pertaining to the labeling 1, 2, 3, 4 A diagram of a carriage bolt. 1. Bolt head 2. Round part 3. Square part (or carriage) 4. Bolt threads —Preceding unsigned comment added by 61.90.18.43 (talk) 04:00, 15 February 2011 (UTC)

I note that all the pan head screws I have seen actually have a chamfered/rounded lower edge to the head (it makes sense since the screw is pressed rather than cut). You can just see it in the pictures here:http://www.indiamart.com/chintamani-industries/machine-screws.html, or here: http://img-asia.electrocomponents.com/catimages/R5465604-29.jpg, but for some reason it is rarely shown on diagrams. — Preceding unsigned comment added by 203.206.162.148 (talk) 12:03, 19 September 2011 (UTC)

Thread Rolling Diagram needed

The article needs a diagram to show how the dies are used to roll threads. There are two or three basic machine types. One rolls the thread between two flat dies (one stationary, one moves at right angles to the shank (back & forth). Another type of machine rolls the thread between two arc dies, one concave, one convex. One or more convex dies is mounted to an inner shaft which rotates. The concave die is fixed. The bolt/screw is rolled between the dies, being inserted on one side of the fixed die, and rolling off completed on the other side. A third type is used to create threaded bar stock (and to roll shot). This machine uses cylindrical dies, and both dies rotate. The dies rotate in the same direction so that the bar stock rotates in place(the opposite direction) along its axis. The rotational axes of the two dies are not parallel but are offset by a bit so that as they rotate, they pull the barstock through the machine.

Note also that the die rolling process can shape the shank of the bolt or screw. --71.214.233.109 (talk) 18:15, 14 July 2010 (UTC)

See thread rolling. Wizard191 (talk) 18:58, 14 July 2010 (UTC)

Peter Horn edits about wood screws

Peter Hom added the following to the wood screw description section:

A wood screw is defined as a male screw made of a metal with a slotted head and sharp point. A wood screw is commonly furnished with a flat, round or oval-head.

Twinfast screw A type of wood screw with two threads (i.e. a lead of 2), so that it can be driven twice as fast.

There are some problems with these edits I think:

1. No citation for the definition of wood screw provided.
2. The definition is highly non-standard by today's usage. Many wood screws and almost all wood screws used in commercial or professional woodworking would not use a slotted head.
3. If a source for a current definition of wood screw can be found it should be used as the primary information for the section and the original sentence can be replace with it.
4. Today pan head screws are much more common than round head screws and round head screws are almost never used in any kind of commercial applications.
5. Are twinfast screws still available today? The reference is from a 1957 book. I found Twin fast being used as a trademark for self drilling screws on the internet. There might have been a market for a doubly threaded screw in 1957 when most wood screws were still driven by hand. I do not know of any usage today when almost all wood screws are power driven.

--Davefoc (talk) 06:45, 15 February 2011 (UTC)

With respect to the twinfast screws, I did some research about them recently and couldn't find any modern references to them. But I could have missed it, because I'm not familiar with them. Wizard191 (talk) 18:33, 15 February 2011 (UTC)

I also did some research and the situation seems confusing. It appears that Twin-fast may be a trademarked name which is applied to screws that don't necessarily have a lead of two. It also seems that twinfast is used generically also to describe a screw with a lead of two. It seems the term may be used often enough to justify some mention of it, but I'm still not quite sure what it is. Peter Hom has continued to make edits in a way that suggests he is not aware of this discussion of his edits. Perhaps something could be done to make him aware of this section? --Davefoc (talk) 02:39, 16 February 2011 (UTC)

I did a little more looking around: Double lead may be a generic term for what a twin-fast screw is. However double lead might apply to any screw fastener or device with a lead of two whereas twin-fast may be a more limited term. These are the most relevant sources I found:
http://www.deerwood.com/catalog/DeerwoodWoodFastenerGuide.pdf
http://books.google.com/books?id=HCEDAAAAMBAJ&pg=RA2-PA207&dq=twin-fast&hl=en&ei=2-pcTcPrAYG4sQOHjNniCg&sa=X&oi=book_result&ct=result&resnum=8&ved=0CEcQ6AEwBw#v=onepage&q=twin-fast&f=false
The second source is from a 1952 Popular Science magazine that says that the twin-fast screw is a new invention.
I never found the original source of the term twin fast although I believe it was at least originally a trademarked name. --Davefoc (talk) 09:25, 17 February 2011 (UTC)
I had begun to suspect that fine thread drywall screws were twinfast but this is confirmation:

Fine thread Drywall--Sharp point: A bugle head screw with twinfast thread, extra sharp point and black phosphate finish.
Fine thread Drywall--Drill point: A bugle head screw with twin lead spaced thread, self drilling point and black phosphate finish.

From: http://www.mutualscrew.com/media/refGuides/Stdrywallf.pdfDavefoc (talk) 10:06, 17 February 2011 (UTC)

This is good info, is there any way you can incorporate any of it? Wizard191 (talk) 02:43, 18 February 2011 (UTC)

Thank you, I am not sure exactly how to proceed. Some thoughts:
Wood screws issues

1. Wood screws only with slotted heads - this one is simple, if wood screws were ever defined as having slotted heads only this is certainly an obsolete definition now. But finding a good current documented wood screw definition may be difficult.
2. Wood screw problem in general - Rolled thread wood screws replaced all wood screws with cut threads quite awhile ago in construction and woodworking. The old fashioned screws have no usage at all I believe beyond their use for amateur repairs and perhaps some use by people trying to duplicate old furniture fasteners. The problem is finding sources that document this (assuming I'm right). Another issue is that screws used for fastening wood are evolving and there is a class of screws that are occasionally called construction screws that vary from manufacturer to manufacturer but I suspect that they are all much better than what has been available in the past. I just used some screws on a renovation project that I was doing that drove much easier than the screws I had been using and yet were significantly stronger and had enough corrosion resistance that they were rated for use with the new treated lumber. I am not sure what the manufacturer called them though(I'll look the next time I get a chance), but I don't think it was wood screws. The term construction screws doesn't seem to have been standardized on and I couldn't find a documented definition of that term.
   

Twin-Fast issues

1. The term Twin-Fast seems to have some usage as a brand name. I think, but I'm not sure, that Asian manufacturer(s) bought the rights to the name and use it as a name brand. This seems like it might be an example of that: http://www.allproducts.com/twfastener/changy/05.html
2. Even when it is used in a generic sense the term seems more like an adjective as in twin-fast wood screws or twin-fast drywall screws or twin-fast self drilling screws so just describing it under wood screws may not be entirely correct.
3. It's not clear how to spell it. twin fast, twinfast, twin-fast, and Twin-Fast are all present on the web.
4. Double thread and double lead are used occasionally as an alternative name for a twin-fast screw but I haven't found a formal definition or enough usage of those terms to verify that they are good equivalents for twin-fast.

I found a mention of a patent for twin-fast screws but I couldn't find a patent for them using any of the on-line patent search tools. I wouldn't be surprised if somebody applied for one and got shot down because of earlier art on double leaded screws.Davefoc (talk) 06:25, 18 February 2011 (UTC)

Dave, you might want to break up this discussion, because you are now talking about two topics, wood screws and twin fast screws. I was confused earlier and thought we were just talking about twin fast screws. From a search of trademarks in China and the US there are no active trademarks for "twin fast" or "twinfast". The only place that the trademark is active is in Great Britain; see [4], which shows that Trifast PLC owns it. Their website is http://www.trfastenings.com, but a search of their site shows that they don't produce it anymore. As such, it appears to have become a generic term for a wood screw with two starts. Wizard191 (talk) 16:03, 18 February 2011 (UTC)

Thanks Wizard191, I had also looked for twinfast trademarks and patents and I had found neither (except for it use as a trade mark for a diet supplement). That was some pretty good searching to find it in the UK. I am now convinced that it is a legitimate screw term that is used commonly enough that it should be included in the article. There is the remaining issue of how to treat the fact that it is more of a general adjective than just describing it in the wood screw section might imply. I would like to have found a quantitative description of its advantages and some specific information about its origin. I didn't find either. However, I am afraid that my various ramblings in this section have made it difficult to discuss anything here and I think you are right that new sections would be in order to break apart the issues.--Davefoc (talk) 17:49, 18 February 2011 (UTC)

Lost info about wood screws

All this info was lost in the merger/redirect: [click "show" at right to view]

A wood screw is defined as a male screw made of a metal with a slotted head and sharp point. A wood screw is commonly furnished with a flat, round or oval-head.

Briefs

In the manufacturing of wood screws, normally, steel with low carbon contents is used as a metal, manufactured by steel mills in the shape of billets which are purchased by wire rod manufacturing mills. This wire rod is further drawn by wire drawing units into different sizes of wire, required by screw or fastener manufacturers. Drawn wire has a variety of other uses as well.

Process

A wood screw passes through the following processes before coming to the packing department in a wood screw manufacturing factory where three separate machines are used for heading, slotting and threading to manufacture wood screws.

• Heading
• Slotting
• Threading
• Polishing
• Galvanization, Blackening, Coating (these processes are omitted when not required by users or sellers)

Heading

This process is called cold forging. Wire coil is put on a stand and wire is fed into a heading machine known as the Header. This wire should not be rusty. The wire is cut into a specified size by a cutting mechanism and is pushed forward towards a die hole. A punch, fixed on a moving block, punches this wire into a die made of Carbide, encased by a protective steel covering or a die of any other suitable material to make a plug. Then a second punch presses this plug to form a blank. The shape of the head is formed according to the design of the second punch. For a flat head wood screw, a flat punch is fixed. Half round or phillips head wood screws are manufactured by grooving or embossing the shape as required on second punch. When the blank is made, a pin moving in the round die, pushes the blank out. This heading machine is also known as the Double-stroke Header. Frequent lubrication is necessary to all parts of the heading machine. Before introduction of the Double-stroke Heading machines, Single-stroke Headers were used to make blanks but are obsolete now.
For the working of a Single-stroke header or "former" see also bolt manufacturing process.

Slotting

Blanks made by the heading machine are transferred to the slotting machine after polishing. Polishing is a necessary process to clean oil, dust or rust from the blanks. Rust or corrosion can damage or reduce the life of the cutter used to make slots. Blanks are put in the hopper fixed on the slotting machine, and they slide down through railing towards the rotating grooved dial which moves them towards the round cutter which is fixed on rotating adjustable shaft. Regarding the cutting speed, it is constantly proportion to the rotation of the dial. The cutter is controlled by a separate motor in some other models of slotting machines. The cutter makes the slot in the centre of the blank's head. When the blanks reach down they are dropped. Continuous lubrication is needed to increase life of the cutter. The process of slotting is skipped when the slot is made on the head by second punch on the heading machine. Slotting machines perform their function at high speed reaching up to 1600 pcs per minute (theoretically). In practice, however, a much less number of pieces is manufactured than claimed by the manufacturers of machines.

Threading

Feeding Finger at work

Threads are made either by rolling or cutting.

Rolling

After being polished the blanks are put in the hopper fixed on the threading machine, and they slide down the railing towards dies. Two flat dies are used, one is stationary and other is moving and the rolling faces of the dies are located opposite each other. One blank at a time is pushed towards the dies with the help of a plate known as the feeding or the starter finger.

Flat die moving direction

When it is gripped between hardened steel dies, the moving die rotates it and threads are formed(see notes 1) and a point(see notes 2) is made as per threading dies. The moving die is fixed in a die pocket on the block which moves further ahead and the screw is dropped(see notes 3). Threading machines perform their function at a high speed. The process is called cold forming and continuous lubrication is required to keep the dies below certain temperature.

Notes:

1. The threaded faces of these dies are pressed against the periphery of the plain cylindrical blank and re-form the surface of the blank into threads as the blank rolls on the die faces. The working faces of the dies have a thread form, which is the reverse of the thread to be manufactured. While penetrating the surface of the blank, the dies displace the material to form the root of the thread and force the displaced material radially outward to form the crests of the thread. The blank has a diameter part way between the major and minor diameter of the thread. There is no appreciable axial movement of the blank during rolling. The diameter of the finished thread is controlled by the diameter of the blank and the distance between the faces of the dies and the finish end of the stroke.

2. A small material is cut-off from the point.

3. On some type of work, it is necessary to employ a "Knock-off" device to prevent the finished screw etc. from being caught by a return motion of the dies. Some machines are equipped with such a device, if not, then it is a simple matter to make one and attach it to the machine.

Cutting

The other method of making threads is cut-thread. These machines are different form Thread-rolling machines. Blanks slide though rail from the hopper (different than the hopper used in thread rolling machines) and are gripped by feeding finger one by one. The feeding finger presses down and pushes the blank into spindle head and moves up to grip the next blank. The timing of this mechanism is controlled by gears and a rotating cam along with other cams. As soon as the spindle head is closed, and the head of blank is gripped, a cutting tool moves forward to cut the other side of blank to make a point. While this tool is moving back, another tool fixed on a shaft starts cutting the threads. Cutting of threads is a three to five steps process depending upon the length and the diameter of blank. When the threads are cut and the spindle is opened, the feeding finger comes down, pulls out the screw, feeds in the next blank, moves up and before it reaches its original position, a shoot ahead part takes the screw from it.

Polishing

Polishing of blanks is repeated after they are made, slotted and threaded. A hexagonal steel drum is used for blanks polishing and a hexagonal drum made of wood is used for polishing after threads are cut or formed. Wood and leather waste is jointly or separately put inside the drum along with blanks in humid weather. Wood waste alone can do the work in dry weather. When these drums rotate, wood and leather waste absorb oil and continuous rubbing cleans and polishes the surface of blanks and screws.

Galvanization, Blackening, Coating

The process of hot-dip galvanizing, blackening or coating is done only when it is required by wholesalers, retailers or is desired by users.

See also

• Blackening (chemistry)
• Fasteners with a tapered shank (self-threading screws)
• Galvanization
• Heading (metalworking)

{{DEFAULTSORT:Wood Screw Manufacturing}} [[Category:Metalworking]] [[Category:Screws]]

It might have been useful to retain this info. Peter Horn User talk 02:19, 16 February 2011 (UTC)

I just noticed this new section. I don't know if Peter Horn was aware of the section above this. This section introduces a new issue about whether a lot of information about the manufacturing of screws should be added to this article. I think almost certainly not. The article is already on the long side and detailed information like this should perhaps be part of an article on screw manufacturing but is significantly over detailed for this article IMHO. I think most of it should be removed from the discussion section also because it unnecessarily takes up a lot of space.--Davefoc (talk) 02:46, 16 February 2011 (UTC)

That would esentially mean reinstating the Bolt manufacturing process and the Wood screw manufacturing articles and combining the now lost info into one article.

I used {{hidden}} and <div style="color:purple"> tags to package the content above more comfortably (click show/hide). Regarding spinning the mfg processes back out into separate articles, IMO this is reasonable to do, because there's enough content to justify separate articles (e.g., purple above), and enough content to make one article too long. Threading (manufacturing) is a more general article about all possible processes for thread generation of any kind. I feel that there's room also for article(s) (1? 2?) on bolt / machine screw mfg and wood screw / sheet metal screw mfg in particular. With links between the 3 (4?) articles as needed. Regarding definitions of the terms, all I can say is that it depends on who you ask and there's no one right answer, so any changes need to be in addition to what we've already hashed out with extensive work and discussion, rather than replacing any of it. See earlier talk on this page and its archives for details. I still like Wizard191's idea to use a table instead of a list. Guess those are all the thoughts I have for tonight. Off to bed. Later, — ¾-10 04:51, 17 February 2011 (UTC)

Sorry for the very belated reply, but I did the merges because really most of the content is really describing the specifics of each sub-process used to make a screw; specifically: heading, thread rolling, machining, and coating. Each of these are vast topics that ought to be discussed in their own regard. As such, I don't support having separate articles about screw making, because they will be copies of these other base processes. Instead how these processes are ordered and used ought to be covered with links to the main article. On a side note, I'm stilllllllllllll working on merging most of the heading section to heading (metalworking).

As for the table thing, I started that too, at User:Wizard191/Sandbox2. Wizard191 (talk) 02:56, 18 February 2011 (UTC)

I came to this page looking for information on the size markings of woodscrews, but there is nothing. Please would someone add this ?

Also, I would like to propose that the woodscrew information that was deleted should be fully restored, as it is both important and interesting. This could either be on this page, or on a page devoted to woodscews, considering the vast amount of information on all types that has been accumulated to date. Darkman101 (talk) 01:00, 26 July 2012 (UTC)

On a side note

Based on all of the above I started the following discussion which might be of interest to those here: Wikipedia_talk:WikiProject_Metalworking#Heading_.28metalworking.29_and_upsetting.

Screw Dimensions

The correct method of specifying the dimensions of different types of bolts is summarised clearly here: http://www.hintsandthings.com/workshop/measuring_fasteners_screws.htm

This is particularly relevant to the length of CSK screws & bolts, which causes confusion if done incorrectly. I suggest adding this information in a separate paragraph. GilesW (talk) 00:06, 27 June 2011 (UTC)

Addition

A new editor, Glooop, made the following addition to the introduction, but not in the right place. Perhaps it can be worked into a scientific description:

"A screw is also an inclined plane wrapped around a cylinder."

Amandajm (talk) 06:02, 31 March 2012 (UTC)

No, its not. this more closely defines a screw thread but not a screw. — Preceding unsigned comment added by 205.243.112.221 (talk) 21:11, 28 November 2012 (UTC)

The view of a screw in simplest theory as an inclined plane wrapped around a cylinder is already mentioned in the lede of the "screw (simple machine)" article (which is the most appropriate place for it), but Glooop's edit was natural enough, as the limitations of the hatnote prevented that from being easily noticed. A good way to address this is to arrange the hatnotes so that screw [fastener] and screw (simple machine) can be jumped between directly. Then Screw (disambiguation) for all the rest. I just evolved the hatnotes to accomplish this. The added navigation power from the hatnote improvement will help to prevent other users from thinking that the simple machine theory is "missing" from the screw [fastener] article in future edits. Thanks, everyone, for your efforts. — ¾-10 17:15, 31 March 2012 (UTC)

I think your edit was an improvement, ¾-10. Awhile back, one of the editors of this article suggested that the name of the article should be something like "Screws and Bolts" which would have reduced confusion on this issue. But, despite the brilliance of the suggestion, there wasn't a consensus for the change and the title of the article remained as it is. Along the lines of your change, it seems like this sentence in the lede should be removed also: "More generally, screw may mean any helical device, such as a clamp, a micrometer, a ship's propeller or an Archimedes' screw water pump." --Davefoc (talk) 23:31, 31 March 2012 (UTC)

The problem was not with the information, but the placement of it, which didn't follow through from the previous sentence. I think both could be incorporated, but I'd rather it was done by someone who has a particular interest here. My tiny brain is stressed to the max with Romanesque architecture. Amandajm (talk) 01:55, 1 April 2012 (UTC)

When I noticed the sentence you added I saw it as a generalized description of screw, which I thought was outside the topic of this article. I think I misunderstood your intent now. But I'm still not quite sure of what your intent was with regard to the information you (Amandajm) added. Was it to provide information about how one might understand the operation of a screw fastener? Or perhaps it was to show how a screw fastener was a kind of screw in the general sense of the term?

I continue to think this sentence is outside the scope of this article: "More generally, screw may mean any helical device, such as a clamp, a micrometer, a ship's propeller or an Archimedes' screw water pump." This does sound like something that belongs in the screw(simple machine) article. --Davefoc (talk) 07:38, 1 April 2012 (UTC)

Staining wood

If the reason for staining wood is rust, then stainless steel would work the same. It is not the reason for using brass.

Reasons for using brass would be aesthetic, perhaps avoiding interference or reception of electromagnetic radiation. — Preceding unsigned comment added by 31.210.187.89 (talk) 19:36, 17 November 2012 (UTC)

reasons to use brass hardware include not sparking when struck with a steel tool. required in explosive environments. In some cases non-ferrous tools are used for the same benefit. Ken (talk) 16:53, 28 March 2013 (UTC)

Phillips vs Cross recess

I note almost universal usage of "Phillips" within the text to descripe the more generic cross-recess drive type. Phillips is a trademarked name and as such refers to a specific manufacturer's product. While many patents have expired, the correct term is "cross-recess". Phillips, JIS, JCIS and others are sub-types of cross-recess drive.Ken (talk) 20:55, 4 March 2013 (UTC)

Woodscrew Size Conversion

I came here looking for a Woodscrew Size Conversion Chart, between metric and screw number sizes. Please can anyone add a chart or a link to one ? Many thanks ! Darkman101 (talk) 19:32, 7 August 2013 (UTC)

Order of Sections

I think the order of sections in this article is a bit odd. I would have expected history to be first, followed by types of screws. It seems strange to me to have "differentiation of screws and bolts" as the first section. I don't think the majority of people come to this page looking to learn about the differences between screws and bolts; I'd imagine that history of screws and screw types are the most frequently sought after sections. — Preceding unsigned comment added by Blelbach (talk • contribs) 05:34, 19 October 2013 (UTC)

History

When was the wood screw developed? The nut-and-bolt? When did they become cheap enough for common use? Paul, in Saudi (talk) 14:18, 1 November 2013 (UTC)

The thumbnail answer is that both are quite ancient in terms of invention. The ideas stretch so far back into antiquity that there's no compact invention storyline such as those for many more modern devices such as, say, the telegraph or phonograph. But neither became cheap and widespread until the late 18th into the early 19th century, when they both did so during the same era. Even so, they were still more expensive and less ubiquitous than the average person today would readily appreciate. (For example, even after wood screws were a viable option, carpenters often didn't feel the need to use very many; the preexisting material culture had inertia. The same was true of threaded bolts and nuts for metal fabrication. For many more decades it remained common to build a lot of things—from barns to boilers—without very many screw threads.) Throughout the rest of the 19th and the beginning of the 20th centuries, they continued to get cheaper and more widespread.

The complete history is complex and interesting; it is broad enough that it is touched on in various Wikipedia articles. Screw > History gives a good overview. The top 4 links listed under Threading (manufacturing) > History round out a multifaceted view.
— ¾-10 22:52, 1 November 2013 (UTC)

I am an Old, Old, Man. So there was a history section and I just skimmed over it? Please excuse me. Paul, in Saudi (talk) 04:21, 2 November 2013 (UTC)

Quite alright, I do that myself from time to time. — ¾-10 22:43, 2 November 2013 (UTC)

What's mean of R.H.P.M.S and F.H.P.M.S?

We are choosing some screws for metal door use, and would like to find the mark's means. Thanks in advance. — Preceding unsigned comment added by 183.26.40.117 (talk) 01:06, 7 December 2013 (UTC)

Abbreviations: FHPMS, flat head phillips machine screw; RHPMS, round head phillips machine screw. For more info on head shapes, see Screw > Screw head shapes. For more info on screw drive types, see the list of screw drives. I will gather together some more of these abbreviations and their expansions and add them to this article or a related article sometime (maybe today?). Regards, — ¾-10 18:44, 7 December 2013 (UTC)

Well done Three-quarter-ten. I didn't have a clue. I don't think I've ever seen those abbreviations before. I took a look on the internet and didn't get any hits. They might be old. Round head screws aren't used in manufactured items anymore and I believe the current standard books recommend that pan head screws be used instead. Davefoc (talk) 07:58, 8 December 2013 (UTC)

Thanks. Yeah, abbreviations of that type are pretty obscure; there are a few that non-fastener-specialist machinists and engineers may know, which are SHCS (socket head cap screw), SHSS (socket head set screw), and BHCS (button head cap screw). But the rest are so cryptic as to be of little use outside of fastener company internal communication. When I get time I'd like to assemble a list. This would be cool because then when people google them, they might crop up at the top of the results (thanks to being in Wikipedia). — ¾-10 17:40, 8 December 2013 (UTC)

Thanks for explaining these obscure abbreviations. I encourage you to add them to the article, because even the mighty Google turns up little of use. Explaining them in Wikipedia will be a benefit for baffled readers worldwide. Reify-tech (talk) 17:57, 8 December 2013 (UTC)

Inter/national standards

I am finding this page confusing or at least not confidence-inspiring because differences between various national or international standards are not made clear. For example, wood screw gauge is a number in the US and the UK. But is it the same number? Are US inches even the same as UK inches? The page doesn't say, and it refers to gauges without saying which system they come from. Hence, my lack of confidence in the information in this page ... yes, yes, I should add this info myself. But it's not my area of competence, which is why I came here in the first place. 87.113.51.124 (talk) 10:29, 18 March 2014 (UTC)

I've had a quick look at some US and UK wood screw size tables. They appear to be similar but I haven't seen a clear statement that they are the same. Wood screw sizes don't seem to be precisely defined as I see visible variation in the size of (UK) wood screws of the same nominal size. US and UK inches are now both the same size as they are both defined to be 25.4 mm (see Inch). (Prior to the metric definition US and UK inches seemed to differ by 3.7 parts per million.)

In the Lag Screw section I've removed the rider "though this can also refer to carriage bolts (round head)" from the statement "In the United Kingdom, lag bolts/screws are known as coach screws". In UK usage a coach screw only has a tapered wood screw thread. The corresponding parallel-threaded bolt for use with a nut is known as a coach bolt or a carriage bolt. These usages are already correctly shown in the Types of screw and bolt tables. GrahamN-UK (talk) 23:32, 29 May 2014 (UTC)