Sunday, July 3, 2016

Finished riveting the leading edge skin - 2 hours

My buddy Mike dropped by in the evening to lend a hand riveting the last few rivets that remain on the leading edge skin. These are a bit tricky to do by yourself (even though I managed to do it on the fuel tanks) it can be done by yourself, I just chose to get some help and make it easier.

Well.....what a pain the butt. Straight outta the gate we were batting 50% on the first few rivets. Had to drill some out and re shoot. One in particular was MURDER. Must have drilled it out 6 times. Well very frustrating. The rivet just did not want to sit flush. After much frustration we re grouped. I drilled it out to #30 and installed and oops rivet. After that order Mike had the gun a bit different and I held the bar a bit different, and we nailed every rivet after. Sheesh...it is true. Riveting is very much a feel and it takes a few to get it back again.

Started assembling the flaps - 4 hours

I had a little bit of edge finishing to do on the flap ribs so I started the day by taking care of those outstanding items. Once I was satisfied with all the ribs and the spars. I clecoed the assembly together and clecoed the bottom skin on.

Right away I noticed that I was not getting a good fit with respect to the rear spar. The plans want you to first drill the rear spar into the ribs, but I felt uncomfortable with this as there is a bit of play in the skin as the rearmost hole is not drilled. After much thought, I decided to remove the plastic from the skin to ensure a proper fit before drilling anything. I disassembled, used the soldering iron and removed the plastic. Then I re-assembled everything.

I gave it all a good look over. I was still uncomfortable with the fit at the rear. Just a bit of play on the skin/rib. My fear was that if I followed the plans and drilled the rear spar first, I risked poor fitment with the skin and the edge distance for the #30 rear hole is a bit sketchy. So I decided to drill and cleco the rearmost hole on the rib/skin to ensure a good fit. I then drilled the rear spar to the ribs. Now, the plans warns about the possible use of shims between the rib and rear spar. I made some out of 0.025" material, and sure enough it was very tight. I decided to go with a 'liquid shim' as I only needed 0.010" or so. (The Stewart S-51 plans have you use 3m structural epoxy as a liquid shim in places - so I think I can use this method on my project). 
 
 
Next order of business was to fabricate the spacers that get placed on the underside of the ribs. 
 
Simple enough to do but the trick was to match drill them with the holes in the rib. After a bit of head scratching I figured my best bet was to use the fan spacer and clecod 'do according to the holes that I could and that allowed me to use the last hole in the fan spacer as a drill guide for the hole I needed. Worked like a charm.

Lots of monkeying around and I spent more time than really needed, but oh well....it's a Sunday.