|4. Cut the V-groove with a chain saw to a depth of 1/2 to 3/4 in. Remove the waste, then roll the
log back into position and re-scribe the corner notch as well as the log end extending past the
notch. (By cutting the V groove, there is now some space between the scribed log and the one
below.) Cut the notch to the new scribe line and cut the tail end of the log using a gutter adze. This
tool yields a concave groove that is tighter and more attractive at the exposed log ends.
|5. Reposition the log, then pick up one end and drop it into place. This is called "thumping" and it
will leave compression marks on the parts of the log that still need trimming. Make any necessary
adjustments, then pack fiberglass insulation into the groove and roll the log into place. The
fiberglass will act as a sort of "internal chinking."
|With the notching complete, bore a 2-in. dia. hole about 8 in. in from each corner and insert an
alignment peg. The peg should be loose fitting, recessed about 1-1/2 in. below the top of the hole,
and extend about halfway into the log below. Install these pegs every 8 ft. in the length of a log and
within 1 ft. of each window and door opening.
|As you move up the walls, alternate each successive log so that their smaller, tapered ends are not
all on one end of the wall. Once the logs reach waist height, cut out the door opening. Brace the
logs on both sides. Of course, if your cabin is larger than the one shown here, you'll have several
interior partitions. These can either be made with logs notched into the outside walls or with framed
walls later on. Notching the logs is preferred because it yields the same interior finish on all walls
and strengthens the structure.
|When the logs reach the top of your planned window and door openings, brace the walls and cut
out all the openings at once. Then cut a groove, as shown, in the log ends on both sides for a
permanent stiffening spline. Cut and insert the spline and then add at least two more logs over the
openings. The top wall log is called the plate log and it should be pegged at least every 4 ft.
|The roof on the cabin shown is a combination of purlin and rafter construction to give an idea of
what's involved with both. Normally, you would use only one. The purlins are set into notches cut
in the gable ends; the rafters are notched into the plate log and ridge log.
|Once purlins or rafters are installed, apply roofing boards for the roof sheathing. Next, apply 15-lb.
roofing felt and either asphalt shingles or cedar shingles.
|Finally, pre-assemble all window and door jambs, install them in the openings, and add the
windows and doors. Allow 3/8-in. clearance for each vertical foot of opening above the jambs for
the logs to settle. The spaces around the jambs should be chinked with okum (hemp and pine tar).
|Wash the logs with detergent to remove any dirt, and then with a solution of two parts household
bleach to one part water to lift out any stains. Rinse the logs thoroughly with water and let them dry
for a week. Then apply a mixture of one part linseed oil to five parts turpentine to the outside of
the logs. This treatment should be repeated every five years.
|This article is from a Popular Mechanics issue - December, 1983