The Book: Your Log House

9. Timber Layout

From the earliest beginnings of log building, there was a need for near-dimensional timber, that is, timber with definite size and shape. Everything cannot be done in the round with a set of scribers. Carpentry measurements of a conventional sort can be used in the assembly of floor and ceiling joists, carrying beams, rafters, trusses, housed stair runners, half logs, and even kitchen counter tops. The raw log can be used for all of these. The forest or log pile is the only lumberyard needed.

The best way to approach creating the materials mentioned, is to visualize squared timber hiding within the confines of the log. It will be necessary to expose the entire squared timber from time-to-time. But as often as not, only certain portions of the timber are required; for example, Figure 23 shows a floor joist with an entirely flattened top for the purpose of nailing on flooring.

The rest of the hidden beam might as well hang onto the rounded slabs of wood with which it was born. They add strength and save the labor of removing them. At either end of the joist, however, some sort of connection to the wall will be required. Therefore, we simply expose enough of the hidden tenon, the dimensions of which are arrived at in precisely the same way we would layout an entire beam.
There are some rules to follow in these layout procedures in order to produce an entire beam (as shown in Figure 26), or necessary portions of that beam. First, the log should be firmly anchored a few inches above the ground. This will save the cutting edge of the broadaxe and will also get the log to a comfortable hewing position. An easy way to keep the log from moving about, is to wedge it into a notched skid log as shown in Figure 25.

Once the log is anchored and cleanly cut to length, all the reference points of the entire set of timbers should be laid out before any line snapping or cutting begins. This will allow for a better chance of consistent measurement throughout the members. It also saves the time of switching from measuring instruments to tools and back again. Measuring and finishing one member at a time (such as a joist) and then starting and finishing another destroys the rhythm of the job. This tends to create slight differences in the pieces of wood in a situation where being identical is a convenient virtue. What frame house builder would cut one wall stud, measure another and cut it, then put down his saw and measure another, and so forth? There is room for routines and efficient organization of time in every job. Log building is no exception.

To lay out the log shown in Figure 26, for the purposes of making an 8x10 timber, follow the numbered sequence illustrated. Using a level horizontally and perpendicularly, draw the center lines (1 & 2) with a lead pencil (not a lumber crayon). The center will generally be the tape-measured center of the log rather than the pith of the log, which will often have grown in an inconvenient offset position. Next, measure up from center and draw line 3 horizontally. The next step is where builders often take a chance on error. DO NOT ARRIVE AT LINE 4 by measuring down from line 2 to line 4. Rather, measure 10 in. down from line 3 to line 4. This may seem like a small thing, but it is one more way of ensuring maximum accuracy of measurement. I like the expression, “Measure twice, cut once.” This is a good rule — especially for beginners. The same procedure is followed for vertical lines 5 and 6. Before going for coffee, follow the same procedure on the other end of the log or on all of the log ends to be laid out.
If all of this seems confusing at a first reading, do not despair. The following pages include the same procedure in photographically illustrated, step-by step order.

Figure 27 shows the other end of the log laid out at Figure 26, that is, the top end or small end. Indeed, it is the small end that largely controls the dimensions of timber that can be taken out of the log.
At this point, I would like to mention an important fact about using chalk lines. In both of these drawings the arrows drawn indicate the direction to snap the chalk line. Always snap the chalk line IN THE DIRECTION OF THE CUT. In other words, the direction of the intended fall of the hewing axe will determine the direction of the snap of the line. Many good timbers have been destroyed by imprecision or ignorance in this matter. This rule is always true.

To anchor the chalk line at its beginning end, simply loop it onto a nail hammered approximately in the center of the log end. Run it through a couple of knife cuts as shown in exaggerated fashion in Figure 27. Anchor the line in similar fashion at the other end and grip the line near the center of its span. Pull the line back to near breaking point. When you have sighted it perfectly vertical or horizontal (depending on which line you are working on), let it snap. Rarely can the same line be used to indicate adjacent faces of the timber.

With all this layout work done and with the log still in its first position, the top face (represented by line 3) can be scored with the chainsaw. With a quarter turn of the log, face 3 can now have the bulk of the wood chopped off.

After the slabs have been chopped off, face 3 can be hewn off with the broadaxe. Now, one of the formerly vertical faces will be in a horizontal position and ready for line snapping and scoring. The procedure of rotating and hewing is repeated. For greatest accuracy in hewing, HEW ONLY HALF-WAY DOWN, but of course, all the way to the other end. The bottom of face 3 will eventually come up again. The other half can be hewn off. Unless the wood is of particularly good grain, hewing right through from top to bottom will result in breakage at the unseen line. Railroad tie-hackers always hewed the entire face in one operation. Carpenters rarely did.

Generally hew with one knee on the log and the other foot on the ground. Some builders are more comfortable walking beside the log. Tie-hackers usually walked along the top of the log and performed the job with a full swing of the mighty axe. For many, this technique took years to perfect. The carpenter-hewer can perfect the less dramatic technique with a week or two of constant hewing.
A brief word about scoring is in order here. If, by using the chainsaw to score, slight chainsaw marks are left, simply plane them across the grain with a slick or hand plane. If a heavy axe is used, the overscore marks are pleasing to the eye. With an axe, always score in the same travelling direction that you intend to subsequently hew. This will help to keep your broadaxe from glancing off the log and possibly slicing some part of your leg. Hewing is pleasurable and satisfying work.

Reference to this chapter will be made throughout subsequent processes in this book.

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