Trimming RV-8 Canopy

I have begun to fit my canopy. Started trimming little by little. Vans sends the canopy with a trim line taken directly off one of their own. So I obviously did not use that line as my first cut. Per the plans, the front of the canopy (which will be the wind screen) should be 3.5 inches aft of the bulkhead in front of the instr panel.

When I place the fwd part of the canopy at the designated mark, the rear of the canopy is about 2-3 inches longer than the rear of the slider bow. I have measured 100 times and the rear bow is .75 inches above the slide cap as required. Even if I cut at the mark Vans provided as a guide, appears 2-3 inches more needs to be trimmed from the rear. Called Vans and they said seems like a lot. They said to first focus on getting the front trimmed before working on the rear. I've done so, but have trimmed about 1/2 beyond their provided mark in the front.

I have not trimmed enough for the windscreen to rest on the front roll bar, as it's still about 1 inch higher, but I am afraid to trim any more before understanding what's going on with the rear. Is my plane shorter than others? Is the canopy in the finish kit longer than usual? I am worrying for no reason?

Any suggestions from you seasoned builders?????

Canopy Trimming

You are right to be careful. Don't trim too much. I saw exactly the same thing you did. I've got 6 articles with pictures on how I did it here:

http://www.rv8.ch/article.php?story=20050614184749626

Next I'll be taking on the skirts.

Courage!

Charlie,

No one photo-documents as well as Mickey, so definitely look at every one of his pictures carefully. On several of the "art project" jobs that I have done on the RV-8 (Canopy, skirt, Baffles, etc...) I have printed out a package of pictures form the good web sites to have in the shop with me for reference. If it wasn't for the guys that take the time to do those sites, I'd be in serious trouble!

I just finished putting the first coat of primer on my skirt, so my canopy experience is recent. First advice - have courage! It is tedious, but not as terrifying as you might think. To summarize, I concentrated solely on the forward trimming, getting the front edge to sit down on the fuselage until the whole thing rested on the roll bar. I used the 3.5" line religiously each time I set the canopy on for a fitting. The only time I trimmed the sides and rear was when they settled down onto the fuselage and prevented the rest of the canopy from settling. Doing this, I had no problem at all with the thing getting to short in the rear. I did a lot of notching for the rib tubes, just to let it settle down, but by the time I was finished, and trimmed the sides to the right length, most of the notching had been trimmed away - just little scallops were left.

Make the "big cut" as soon as the thing rests on the roll bar. The canopy fitting goes pretty easy from that point on.

I kept telling myself to relax - I have better than $85K in the project so far, and a new canopy is only $400 from Todd's - if the WORST happened! The sacrifice is not the money, it is the time that you have invested. So if you are going to screw it up - do it early!

Paul Dye
Sanding and Filling, Sanding and Filling........

Trimming the canopy

Paul - thanks for the kind words. Your tip on not cutting the rear of the canopy before the front is trimmed saved my bacon!

Canopy Trimming

Thanks guys for the great advice, pictures and encouragement!!!! I'll continue with the small amounts of trimming, focusing on the front.

Just in case, who is Todd and how would I get a hold of him just in case?

Trimming Finished

Mickey & Paul-

Thought I'd drop you a note to let you know how the trimming went. After 100 trim sessions in the middle of the midwest heat wave, the canopy fits like a glove! Patience and persistance paid off. The big cut ended up being a none event. Everything fits and looks great! Holes are drilled and clecoed, ready to install some temporary rivets.

Thanks again for your help and advice.

Charlie