Two weeks ago, I left off getting ready to match drill some of the rear spar double plates. I spent last Saturday at the doc-in-a-box waiting (and waiting) to get a prescription written. Sigh! I dove right in this Saturday and got all the match drilling done. Watch the holes carefully, it is easy to miss one. I almost did, but caught it when I double checked.
One of the doublers needs a cut out for the aileron push rods. Vans provides templates. Since I have the PDF files for the plans, it was pretty easy to just print out those templates. Do be careful that they are printed at 100% size. My son came out to help (and get some lunch at the Chinese restaurant!). I mounted the templates on the doubler plates (I just clecoed them in place) and he drilled the pilot holes on the drill press. Since the clecos raised the plate up a little, I used a leftover piece of styrofoam as a waste board. The clecos pressed into the foam leaving the doubler plate level for the drill press.
The original instructions have you drill a pair of 1″ and (it says 3/8″ but is really) 3/4″ holes and then clean up the edges. The newer instructions have you trace the outline of the aileron push rod hole. I did it the original way (mostly). I used some spade bits to cut the holes and then cleaned the edges up with a file. It came out pretty close to the original hole. I think the new method would have been easier… maybe drilling a bunch of #30 holes just inside the perimeter and then filing to shape.
The next tedious step was deburring and edge filing. Most of these I handed off to my son. He did a great job and it really sped the work up.
I got everything primed. There’s still some match drilling and countersinking to do, so there’s a bit of touch up to do. Easier to have all the pieces primed now for handling. I assembled both rear spars. Next time out, I’ll finish the match drilling and counter-sinking and I’ll rivet these up. Maybe I’ll even get a couple of top skins clecoed on!