I'm currently building a replacement set of flaps (long story) and remember that I had a heck of a time keeping them straight the first time around. I took the advice of several builders and built a super straight box out of MDF and lots of glue and screws. This little coffin is the same size as a flap and weighs about 20 times as much, but is dead straight so thanks to all who advised. I was able to cleco much of the structure to the box while drilling skins to ribs and such, and things came out perfect.
Now for the non-standard part. I felt that on my first set of flaps it was actually possible to drill things perfect and still build in a bit of twist/warp during the riveting process due to the v-jig being less than perfect, so this time I did the following:
1. Rivet lower flap skin to inside ribs.
2. Rivet false spar to inside ribs.
3. Cleco the whole shebang together (except for the spar), place double-sided foam tape on lower skin along rib rivet lines and stick this dude right down onto my super strong elf coffin.
4. Reach in and rivet upper skin to ribs.
5. Remove, flip, and shoot rivets along false spar.
6. Install spar.
If anyone is wondering how to get it unstuck from the box, you make a garrot (sp) out of some safety wire and just pull it between the box and the flap one tape strip at a time. Works like a charm.
Now for the non-standard part. I felt that on my first set of flaps it was actually possible to drill things perfect and still build in a bit of twist/warp during the riveting process due to the v-jig being less than perfect, so this time I did the following:
1. Rivet lower flap skin to inside ribs.
2. Rivet false spar to inside ribs.
3. Cleco the whole shebang together (except for the spar), place double-sided foam tape on lower skin along rib rivet lines and stick this dude right down onto my super strong elf coffin.
4. Reach in and rivet upper skin to ribs.
5. Remove, flip, and shoot rivets along false spar.
6. Install spar.
If anyone is wondering how to get it unstuck from the box, you make a garrot (sp) out of some safety wire and just pull it between the box and the flap one tape strip at a time. Works like a charm.
