Time to make the Swiss Cheese

Things went well with the assembly and clamping of the first truss.

Came up with a good idea for holding the backer block in place when drill the trunnel holes to miminize the damage to the wood surface as the drill bit exits. On the South Wayne bridge I used my hydraulic floor jack to hold the backer piece up tight to the truss. The jack was heavy, bulky and slow, requiring several pumps to raise the jack each time. After some thought and digging through my shed I found an old air cylinder with a 3 inch stroke. Made a base and plumbed in a supply and exhaust valve. Works like a charm. Will be a nice addition to the ol' bridge building tool kit!

Do to the heat again today (over 100 degrees for the past 5 days) had to take a break and put off drilling until things cool off weather wise. Real heat wave this summer in southern Wisconsin. One for the record books for sure. 

Superior method

Without a doubt laying the lattice out in place and then cutting them is a superior method compared to the way carpenters cut roof rafters. A pattern is still layed out and used though.

In this picture you can see the knots in the chord and lattice piece. Taking advantage of the extra length of the lattice this piece can be slid down and the knot in the lattice be placed below the chord.

With all the first layer of lattice in place now the pattern can be used to layout the length and angles. This method was very organized and efficient as each set of tasks were completed in groups, placing lattice, adjusting for knots, tracing pattern, cutting angles. Saved a lot of time and handling.

Second layer of lattice applied and cut the same way. Good days work!

90 clamps latter and truss number one is coming along nicely. Soon I will have to shift gears and start the cribbing prep work at the site.