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Archive for June, 2012

Drilled Canopy Side Holes – 8 hrs

June 30, 2012 Leave a comment

Saturday Jun 30, 2012

First up this morning was riveting the forward side rail extensions to the longerons. I don’t know why I put this off so long but I knew I should get it done before gluing the canopy so it was at the top of my list this morning. There were a few tough rivets because the rivet is so close to the F-704 bulkhead so I used a couple of CherryMax rivets.

Next I installed the canopy frame, lift struts, and canopy. I spent some time getting the canopy aligned right where I wanted it with a gap of .025 between the aft edge of the canopy and the front edge of the rear window. That gives me some margin for slight shifts and I can enlarge the gap to .06 or so later. Then I aligned and drilled the three little clips I made to help tie the forward edge of the canopy down to the C-702 skin.

For each side I made three small plates to replace the side skirts during the process of drilling the canopy side holes. They are .062 thick and they hold the canopy in the nominal position so it does not bow out on the sides.

Then I drilled through the canopy to the holes in the WD-725 rails. I was going to get inside and drill from the inside out using the rail holes as the guide, but I decided there was a risk I would knock something out of alignment in the process so I drill the holes from the outside using the inner holes as the target. That was easier than I expected. I did not drill the aft most hole on each side because the edge distance on the plexiglass was a little shy. So I have 13 holes on each side instead of the standard 14. But I plan to bond with SikaFlex also so strength is not going to be an issue.

I removed the canopy and cleaned out the chips. To drill the holes in the side skirts I made a dummy piece of canopy from a leftover scrap and drilled a 1/8 hole in it. I used one cleco to center the hole in the plexiglass with a hole in the side rail and clamped it with two cleco clamps. Then I removed the cleco and match drilled through from the inside. I repeated this for each hole.

I also drilled holes to mount the little lift handle on the pilots side of the canopy frame.

Next I needed to countersink the holes in the canopy I just drilled for a #6 screw. Just for practice I made a few countersinks in a scrap piece of plexiglass. The countersinks look nice and clean with a standard countersink bit. No chipping observed. This also gave me a chance to set the countersink cage depth to match the size of a dimple in .032 thick Alclad which I made as a sample.

So nothing left to do but make those countersinks. They are pretty close to the edge of the plexiglass so I was a bit anxious about these but they all turned out fine. Here are a few samples.

Then I drill the holes in the side skirts to #27 and dimpled the holes for the screws. I also drilled out the holes in the WD-725 weldment to #27 for the screws.

The day of bonding is getting close. I can see the light at the end of the tunnel.

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Categories: Canopy, Finishing Kit

Painted Glare Shield and Clips – 1. 5hr

June 29, 2012 Leave a comment

Friday Jun 29, 2012

Tonight I painted the glare shield and the little clips to hold down the canopy along the front. I used flat black JetFlex WR. It cost me $60 to order a quart of this paint but I really like it. I have just recently learned how to really work this paint. I sprayed on two medium coats at high pressure to give a smooth finish, then I sprayed another couple of light coats at about 20 psi to give a nice fine textured finish. It looks very professional. I painted the clips on the side facing the plexiglass so they will not be visible from the inside of the canopy.

Ready to Paint Glare Shield – 2 hrs

June 28, 2012 Leave a comment

Thursday Jun 28, 2012

After work I sanded the epoxy filler I put on the glare shield last night.  I took most of the epoxy off just leaving enough to fill the low spots.

It seemed pretty smooth so I brushed on a coat of UV Smooth Prime because it is thick and fills small voids and irregularities well. I sanded it and it was good to go for paint.

But it was already dark and getting late so I just masked the part to paint tomorrow.

I also did a little work on the release handle in the fuselage. I fit the yellow ball but I don’t have a #16 drill bit so I installed the little spring that preloads the catch against the latch.

Preping Glare Shield for Painting – 3 hrs

June 27, 2012 Leave a comment

Wednesday Jun 27, 2012

Tonight I marked the glare shield for painting and I put down a mask line with red electrical tape. It will lay down in smooth curves must better than masking tape. I also put in the last pop rivet shown here. This one is trailing behind because there was a gap between the skin and the aft tube of the frame so I filled the area with epoxy and flox last night and let it dry over night. Then I drilled out the hole again and simply installed the pop rivet.

Next I scuffed the surface of the glare shield to prepare it for priming and painting. The surface was not as nice as I wanted it to be with little holes in all the pop rivets and some minor waviness around some of the rivets so I mixed up some epoxy with light weight filler and spread a thin layer on to smooth it out. I will let this dry over night and sand it out tomorrow. It may take one or two more cycles to get it smoothed out then I will put down primer. This is all just so it looks nice through the wind screen.

Made Clips for Canopy Forward Edge – 2 hrs

June 25, 2012 Leave a comment

Sunday, June 24, 2012

Not a lot to report today except I made these aluminum clips to help secure the forward edge of the canopy. Them plans describe them as optional. I figure they will be invisible once the canopy installation is complete and can only help strengthen the attachment of the plexiglass to the frame.

More Riveting Canopy Frame – 4 hrs

June 23, 2012 Leave a comment

Saturday Jun 23, 2012

Last night after work and this afternoon I worked on the riveting of the canopy frame. With the exception of one rivet, this thing is done. Some of the rivets were tough to shoot and it helped to have Denise drive the gun on a few while I bucked.

The reinforcement kit is installed also as you can see in this view.

I put it back on the fuselage afterward to check how it fits. Overall, not too bad. I have no complaints on the left side at all. The right side has about 1/8 inch gap between the C-702 skin and the forward fuselage skin. I can play with that a little bit more but if all else fails I can fill it when I do the fiberglass work on the C-702 skin.

Here is a close up of the left side. Nice.

Here is the right side. That gap measures 1/8 inch at the very bottom.

Started Riveting Canopy Frame – 3.5 hrs

June 20, 2012 Leave a comment

Wednesday Jun 20, 2012

This post covers what I did the last two nights.

Last night I did a final fit check of the C-702 skin to the canopy frame. This entailed putting the frame back on the fuselage with the skin to see how much I needed to shim to raise the C-702 skin up at least level, if not slightly above the forward fuselage top skin. It was clear I needed a shim in the center section so I made one from .025 scrap to snap the center eight rivets. Here it is drilled and dimpled. However when I put it in it was a bit too wide causing the skin to rise too mush at each end. So I cut the shim down to the middle four holes only and that seemed about right.

Tonight I finally started riveting the C-702 skin to the canopy frame. For a while I thought this day might never arrive. I was riveting solo so I rigged the frame up to make it possible to reach both sides without holding the frame itself; one hand for the rivet gun and the other for the bucking bar. It was kinda slow going but I got all but two rivets set on the front row and some of those were hard to reach with the tungsten bucking bar. I started working my way up the left side when it got too late to continue so I will resume here next time.