Cupped Logs Fit Snugly
A third method is to use “cupped” logs. The same saddle and notch is used at the corners, but the upper log has a concaved channel cut its entire length, which makes it fit down snugly over the lower log. The cup may be cut with curved-blade adz or with a heavy gouge. This is more work but well worth it. Cut each cup to fit its individual lower log, marking the cup with a pair of dividers to insure a close fit. When you have a perfect cup (which means rolling the log into position several times to try its fit) lay a layer of heavy oakum along the lower log, roll the upper into its final position and spike it down.
The finest method of all is a further refinement of the cupped log style. The upper log is cupped as above but, instead of a simple notch at the end, the upper log is cut out exactly to fit down over the lower tightly, while the lower is not notched at all. Oakum is strung the same as for other methods and laid in at the corners. In the best work of this type no oakum should show. Although the pioneers put their cabins together without nails, they did so because they had no nails to use. To be safe, spike all logs together with 12-inch spikes—the largest size made.
Before you get the walls too high, give a thought to windows and doors. There are two ways of taking care of them. The extravagant way, much used by our forefathers, was to build with logs to the top line of the proposed opening and then cut out a hole the required size. An easier—and less wasteful—way, if you are doing your own work, is to use short logs, leaving a more or less rectangular opening. Then nail a couple of straight boards where your frames should come and saw off the rough projecting log ends as illustrated above.
PLANKS NAILED AS GUIDE FOR CUTTING
LOWER LOG HEWN OUT
Incidentally, in planning your house remember to take into consideration that a log cabin’s interior absorbs a great deal of the light unless—God forbid—you intend to whitewash the walls. Therefore, plan for as many windows as your walls will allow without unduly weakening them or disrupting your interior plans.
Use timber at least two inches thick for window and door frames and wide enough to protrude slightly on the outside of the log wall. The bottom piece—or sill—of the window frames should have a pitch of about one inch to the outside and project two inches to allow for drainage of rainwater. Don’t try to build your own windows. Order them to size from a mill and set them in.