Hewing

A German carpenter (zimmerer) hewing a log into a beam. Note the blue chalk line snapped on the log to which the hewer works.

In some medieval Scandinavian buildings a special method of hewing which produces a herringbone pattern on the timbers, have been used (Swedish: Slinthuggning, Norwegian: Sprettejling). This is a modern reconstruction in Stråsjö Chapel in Hälsingland, Sweden.

Stråsjö Chapel

The word hewing is a general term meaning to strike or blow with a tool such as an axe or sword; to chop or gash. This article is about hewing as the process of converting sections of a tree trunk from its rounded natural form into a form with more or less flat surfaces using primarily, among other tools, an axe or axes. It is an ancient method still used occasionally to square up beams for building construction.

Methods

As an ancient method of conversion, different methods of each step in hewing have developed in history.

Prepare log

After a tree is selected and felled, hewing can take place where the log landed or be skidded or twitched (skidded with a horse or oxen) out of the woods to a work site. The log is placed across two other smaller logs near the ground or up on trestles about waist height; stabilized either by notching the support logs, or using a 'timber dog' (also called a log dog, a long bar of iron with a tooth on either end that jams into the logs and prevents movement). The hewer measures and locates the timber within the log on both ends and marks lines along the length of a log, usually with a chalk line.

Scoring

The next step is to chop notches every foot or two, almost as deep as the marked line using a chopping or scoring axe, called scoring. At least three methods are used in scoring. 1) Standing on the log and swinging an axe to chop the score; 2) In Germany a method of two carpenters standing on the ground with the log on trestles and swinging downward to slice the scores. (see video in link below); 3) A modern method of using a chain saw saves labor and time.

Joggling or Juggling

The pieces of wood between the notches are knocked off with an axe , this process called juggling or joggling. This results in a rough surface pared down just shy of the marked line. Scoring and juggling remove a fair amount of wood, make hewing easier and prevent long shreds of wood being torn off.

Hewing is the last step in this whole process, which is also collectively referred to as hewing. Hewing is done on the logs sides with a broadaxe. Hewing occurs from the bottom of the stem upwards towards what was the top of the standing tree, reducing the tendency of the broken fibers to migrate inwards towards the eventual beam.

It is widely published that an adze was used to hew the top surface of a log flat in the same manner as an axe is used on the sides of a log. However, physical evidence of looking at the marks left by the hewing tools in historic buildings, called tracology, are swung in an arc and thus made by an axe, not an adz. Shipbuilders frequently used adzes in shaping ship timbers, the choice of tool being made by the position of the surface being hewn, the sides best hewn with an axe and the face best hewn with an adze. Historic illustrations do show some Asian carpenters hewing building timbers with an adz. Further smoothing can then be done using a hand plane, drawknife, yariganna (an ancient Japanese cutting tool) or any other established or improvised means.

Some 19th century timber buildings in the U.S. have hewn long timbers in the same framing with vertically sawn and the later technology of circular sawn timbers. The reason for this is the long timbers were easier to hew with an axe than to take to a sawmill due to poor transportation routes.

External links

• Video of the German method of hewing
• Video of a widespread method of scoring a log in the process of hewing