Building the Jig

Building a jig seems pretty simple for someone with a reasonable set of skills and a few hand tools. And about two days later, I finished it. The challenges were finding long enough and strait enough wood from my neigbors scrap pile (with permission of course), coaxing out the bends and bows, leveling the contraption (on a not so level garage floor), and anchoring it to the floor.

One of the best ideas thus far is the attachment of two identical measuring tapes ($4.88 from Walmart) which run the length of the jig. This provides a solid measuring platform that eliminates a tape measure for placing the critically spaced laterals for holding the bulkheads. Using a carpenters tape is not such a good idea, at least not the ones in my toolbox. The end of my tape measure has about 1/8" of play and depending if you are pushing or pulling this can introduce a 1/4" error. This is way to much for an airplane structure in my opinion.

Be sure to buy a metal ruler. It is much more accurate and you can lay it across the jig for perfect alighnment on both sides of the aisle. I had to get creative to get my jig straight.

Things I learned:

1. The measurements called out for jig building do not align with the measurements on the blue prints for the fuselage. There is 3/4" difference to accommodate the mounting of Bulkhead #1 (F402). You'll need to reposition the tape running along the sides of the jig after the jig is finished, should you decide to use the tapes.
2. Using (2)1X6 X16's instead of (1) 2X6X16 will improve the likelihood of a straight jig or at least the ease of straightening a crooked one. Be sure to put the corssmembers and bracing triangles in place before you disconnect your straightening aperatus - unless you want to start over.
3. You have to start thinking about building this fuselage upside down. It can get a little confusing at first.
4. Liquid nails in reasonable abundance does a good job of securing the jig to your garage floor. Be sure it is straight, level, and well braced before doing so.
5. And just in case your wondering, the instructions for the jig are in the plans for the airplane, so don't try to do this in advance (like I did).

Using a chain, 2X4, string, and small spreader to straighten jig