Primed the Rear Spar - 2.5hrs

Not much to report. I prep'd and primed all the rear spar parts.

Working on Mike's Stewart S-51

Mike came over this evening to work on his HS rear spar for his Stewart S-51. He had a look oever my work and I ran through some of my work. It was nice to get his eyes on my work to verify if I am doing things right.

Prep'd the rear spars - 6 hours

Learning from previous experience, I match drilled the rear spar doublers to the rear spar with the drill press. progress was a bit slow, but it was precise.
 
I then transferred the aileron holes to the doublers. As per the instructions I used a unibit to remove as much material as I could. I then tried to use files to finish the holes but progress was extremely slow and I had much material to still remove. I dug out the dremmel with a small sanding drum which worked excellent. At first it removes a lot of material, but as the drum wears down so does its ability to remove material allowing you to easily fine tune the cuts.


As soon as I was close enough, I cleco'd the doublers to the rear spars and very carefully used the dremmel to match finish the holes.
I drilled and de-burred the parts.

Completed tie-downs and started rear spars - 6 hours

I began riveting the nutplates on the tie-down assembly. It went fairly smooth and I am happy with how it turned out. I now see why the use of compact nutplates is not mainstream. Not the easiest to rivet...not impossible,  just no room to work with. My friend later told me that a trick he uses is to use a punch and a back-rivet plate to set them. Good Idea!


I then bolted them to the spars with little incident. I wet set the bolts with primer on the shank. I did notice that one hole was a bit tough to screw in due to the one nutplate being tight. I will have to account for this when torquing.

I then began to trim the rear spar doublers. I sketched the dimensions shown on the plans out on a piece of paper and then transferred to the one doubler. I cut the doubler and used the sanding station to fine tune the piece. I then used that one double to transfer all the cut markings to the other pieces. I then trimmed all the other pieces. Once nearly complete, I cleco'd the pieces together and then finished them with the scotch brite wheel. They are all a perfect match.

Completed tie down spacers - 2 hours

The nutplates and AN4 bolts and washers arrived from Aircraft Spruce yesterday. So I set off to complete the Tie-downs. I figured that the compact MK1000-4 was the best nutplate for the AN4 bolt with the spacer out of all the various nutplates that I ordered. I drilled the holes and de-burred them. I then cleaned the parts and then primed them.

Almost finished Tie-Down Spacers - 1.5 hours

Spent a little time completing the countersinks for the flush rivets in the tie-down spacers. I have to wait for the selection of nutplates from Aircraft Spruce to arrive before I can finish.

I then completed the riveting on the K1000-4 nutplates on the ends of the wing spars.

Worked on the Tie-Down Bars - 2.5 hours

 I built up the courage to fix the oblong hole in the spar tonight. I bolted the whole assembly together including the aileron brackets. I then cut a piece of oak to fit between the brackets and clamped it tight to ensure nothing moved to drill the 1/4" hole for the AN4 bolt. Lots of time to set it up, but I wanted to make sure that there was no mistakes!
 I then set up the drill press. (no way that I am doing that by hand every again!).

Success, the hole came out really nice. I don't think I'll have an issue with edge distances but I will wait to hear back from Vans.
 
 I  received confirmation from aircraft spruce that my various selection of nutplates, AN4 bolts and washers are shipped. Should be able to finish this part off before long.
 
Next I finished drilling the K1000-3 nutplate for the one unfinished side (Once the new AN4 nutplates are in I'll tackle the last one) I then decided to tap the threads on the W-731 tie-down bar. I used my 3/8-16 tapered tap,  secured the tie-down bar in the vice and went to work. It was slow work but it went very well. The tapered tap just fit in the hole and the threads grabbed quickly. I used WD-40 to lube the tap as I went. I'd turn the tap about an 1/8th turn, then back, then turned it again cutting about 1/8 turn, and back, I do this a couple of times and then I'd blow out the chips with air and squirt in some WD-40. Every so often I would back out the tap, blow all the chip off the tap and out of the hole, and stick it back in. Takes a bunch of time, but I am very happy with the results. I tapped just about 1-1/4" deep. This allows a solid 1" of full threads while the tapered end made up the last 1/4".