The 21st Century learning experiences gained as the community, school and businesses design, plan and build a 32 foot long Town Lattice Truss covered bridge for the Village of South Wayne, Wisconsin.
Sunday, April 12, 2015
Squinted half lap joints anyone?
As the cabin approaches full height we will begin transitioning to the task of making the bottom chords for the rafter trusses. These will need to be 18 feet long to provide a 2 foot overhang to protect the log walls. Since Sue only had two 18 foot logs in her group of logs we will need to join two together to get the length we need. Not a problem.
For this joint I think a squinted half lap joint will do the job nicely. A bit tricky to layout and cut but I am sure Sue and John are up for the challenge as they have done very well the 1/2 dovetails for the walls. This first one was made as an example for them to see and put together with screws. We'll see if they want to go with pegs and really get the look of a timber framed truss.
While they were cutting the final wall logs I went to work laying out and rough cutting half of the eleven bottom chords we will need to cover the 24 foot length of the cabin roof (12 foot cabin with 6 foot porches on each end). Sue will be working on laying out the other 11 to match these. Then we'll saw a few by hand with the rip saw to appreciate how it was done years ago, before chainsaws!
Next, we will get down to the business of trimming and fitting the faces of the laps and then sawing up the squints for a tight fit. Again, so there is a real appreciation for that was done by the pioneers years ago. Should be a great experience and a a lot of work, but look what she will have when it's done. Priceless!