1.5 hours
Before I can attach any skins, I have to make sure the wing is square and free of any twist.
Getting the twist out is pretty easy, you just have to lay the wing flat on a table and make the whole thing level. However, I found squaring the wing a little trickier.
The way to ensure the wing is square according to the plans is to set the lateral location of the single hole at the end of the rear spar attach plate at wing station 19.0. That is, the hole needs to be 19" outboard of wing station 0.0, which is the center of the three 1/4" alignment holes in the main spar. You can kind of see this in picture #2 of Sonex's instruction sheet here:
http://www.sonexaircraft.com/documents/instruction_sheets/SNX-W07-02.pdf
I don't have a square that long, and I have the root rib attach angle and the outboard wing attach block in the way anyhow, so I had to figure out a different way to set the 19" dimension.
I started by marking the center of a 1/4" bolt and putting it in the hole at W.S. 0. Then I laid a ruler over that and carefully marked 19" outboard on the main spar.
Next I took a 48" piece of bar stock from Home Depot, cut it in half, bent each end a bit, and drilled a 1/4" hole at the end of one and a #40 hole and the end of the other. Then I bolted one to the W.S. 0 hole, and clecoed the other one to the rear spar hole. Now I can slide them relative to each other and clamp them to set the lateral position of the rear spar.
Finally, I leveled the main spar the long way, and dropped a plumb bob from the rear spar hole down to the main spar. Then all I had to do was adjust the length of my little jig until the plumb bob sat on my W.S. 19 line. That should do it!!
Tuesday, February 28, 2017
Monday, February 27, 2017
Pitot/Static System Part 1 (0.5)
0.5 hours
Not a whole lot to do here yet since my pitot/static tube is still on backorder from Aircraft Spruce, but I did need to get these tubing holder tabs on before I put the ribs on for good.
Sunday, February 26, 2017
Aileron Bell Cranks Part 2 (3.5)
3.5 hours
I went back and replaced all four bushings in these bell cranks, and started over reaming them to try and get the cranks to turn nicely. I got some good info here:
It took a while but eventually I got both of them moving freely with no slack!
Sunday, February 12, 2017
RH Wing Structure Part 2 (3.5)
3.5 hours
More work on the wing structure. I got the rest of the forward ribs and spacers pilot drilled to the spar, then I cleco'd the rear spar to the aft ribs. Everything went together pretty easily and I didn't see any issues, so I went through and updrilled everything. Finally I took it all apart again and deburred all the parts. All that's left is to put it back together one more time for riveting!
All 24 ribs on! |
Rear spar attached |
Updrilling |
Everything deburred! |
Saturday, February 11, 2017
RH Wing Structure (2)
2 hours
Starting on the RH wing structure. The ribs and spars all have pilot holes which appear to match up perfectly, so the only real work required was lining up and drilling all the spacers to match.
All the parts laid out |
Starting with the aft ribs, and all the spacers which needed to be drilled to match the spar |
Aft ribs 1-12 pilot drilled! |
I flipped the spar over and got the first few forward ribs done before quitting time |
Friday, February 10, 2017
Spar/Rib Spacers (1.5)
1.5 hours
It's getting close to time to start putting the wing structure together, but one of the last detail parts required is all these little spacers. There are 0.125" x 1/2" spacers for 10 of the aft ribs, and 0.032" x 1/2" spacers for 8 of the forward ribs. So for both wings I needed 20 of the .125" and 16 of the .032".
I started on the .125" spacers, and I found a sheet of material that would work. I cut one spacer out on the bandsaw and then I realized I had a whole 10' piece of 0.125" x 1/2" bar stock for this very part. So I cut the other 19 out of the bar stock! Hopefully whatever I needed that sheet for didn't need the whole length...
For the 0.032" spacers I just cut a bunch of long 1/2" strips out of this sheet with snips, and then cut them to length.
All 36 done!
Aileron Bell Cranks (2)
2 hours
On to the aileron bell cranks, which will attach to each #9 aft wing rib that I started a while ago. The first step was to press the bronze bushings into each bracket. The holes are way to small to start with, so I drilled them up to the closest size I could and still have an interference fit.
The bushings still seemed a little tight to just force in, so I put the bushings in the freezer for a little while, and heated up each bracket with a heat gun just prior to installing. They went right in with a few good whacks with the rubber mallet.
The next step was to get these steel bushings to go through the bronze bushings and spin freely but without slop.
Anyway, some adjustments required still, but here's what they'll look like on the ribs:
On to the aileron bell cranks, which will attach to each #9 aft wing rib that I started a while ago. The first step was to press the bronze bushings into each bracket. The holes are way to small to start with, so I drilled them up to the closest size I could and still have an interference fit.
The bronze bushing OD is 0.440" |
My closest drill bit (marked 27/64") measured 0.435" |
The next step was to get these steel bushings to go through the bronze bushings and spin freely but without slop.
The steel bushing OD is 0.314" |
The bronze bushing ID is about 0.309" |
The steel bushings initially didn't fit at all. I tried reaming the bronze bushings to 5/16" (0.3125"), but they still didn't quite fit. After some messing around I finally tried drilling the bronze bushings out to 21/64" (my bit measured about 0.325"). This allowed the bushings to finally fit and turn freely, but there is a tiny bit of play in the fit. I'm going to have to do some research and see if it's too much play or if it's OK. Worst case I'll have to replace the bronze bushings!
The RH bell crank turns a lot more freely than the LH, but I can make them even by shimming and/or sanding down the spacer blocks between the brackets. I'm more concerned about the radial play between the bushings though.
Here's a video showing the RH first, then the LH:
Anyway, some adjustments required still, but here's what they'll look like on the ribs:
Ailerons Part 7 (1)
1 hour
I got my super skinny PRG410 rivet puller from ebay, so I was able to go back and get the last few rivets on the ailerons. This thing can get in tight corners, it's awesome! Sonex should add it to their list of recommended tools in my opinion.
The rivets next to the drive rib are a real tight fit, but this PRG410 thing had no problem reaching them. |
The counterbalance rivets are pretty tight as well, but not too bad. |
All flaps and ailerons done! |
Back to the wall of parts they go, until later. |
Thursday, February 9, 2017
Flaps Part 3 (4.5)
4.5 hours
Lots more progress on the flaps! The right flap is done and the left flap is not far behind!
Wednesday, February 1, 2017
Flaps Part 2 (3)
3 hours
More progress on the flaps. The RH one just needs all the parts deburred, and on the LH one I need to fit one more rib plus the hinge and then deburr everything.
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