[cnpeters]

After perusing the archives, I couldn't find an answer to the following as I build my canopy frame - has anyone had problems with the BOTTOM of the tip up canopy frame front skin being proud of the fuse side skin? Mine is almost 3/16" inch out on both sides. It is just the front 3-4 inches and then starts curving in matching the side skin as one proceeds aft to the side rails. I can see where I may be able to use seamers to help, but the frame looks like it may be slightly wide at this point (and too late to correct through the splice plate as all riveted, gooseneck hinges done). I thought I saw a reference where someone fluted the bow of the front frame channel, but that may destroy the nice fit with the front skin gap, where I seemed to have avoided the common bowing skin issue at the 2 and 10 o'clock positions,
I will post pics later when able if the above is not clear.

 

[roee]

I had a similar issue at first, although not quite as much as yours. Anyhow, I found that the issue was simply that the skin needed to continue to curve to match the contour of the fuselage past where the canopy frame channels end. To deal with this I ended up just pre-bending some curvature into that area of the skin before riveting it to the frame, and that worked out pretty well. I used about a 1" diameter dowel and duct tape to do the bending, similar technique as used to roll the elevator and rudder leading edges. A couple of iterations of bending and test-fitting, and voila! If you haven't riveted your skin on yet, then I would recommend this method. If you have riveted it already, then maybe you could use seamers, but then you might end up with more of a straight bend rather than a matching smooth curve.

 

[Greg Arehart]

Carl,

I had (have) a similar issue - both sides out by maybe 3/32. I attributed it to the frame splice and not much I could do to fix it at the time. If I had to do over, I would 1) be more careful on the splice and 2) do what roee did and try to put a bit of bend in the canopy skin. In my case, its too late for either option at this point. It bothers me less with each passing month (if that's any consolation)....

greg

 

[apkp777]

I just did my canopy frame this past weekend. I had everything perfect all the gaps and heights PERFECT. Then I drilled and riveted the splice plates. 1/8 to 3/16 gap at the 10 and 2 positions of the skins. What the heck?

My plan is to "shrink" the skin on the fwd side of the canopy skin. I am going to add some "anti chaffe" tape to the gap and maybe some bending and tweaking of the sub panel flanges to raise the aft edge of the fwd skin.

What a pain.

 

[[email protected]]

hold off on anything drastic...

wait until the top skin is riveted and locks everything in before doing anything... the canopy will move around a bit here and there until all of the skins are riveted in... don't rivet the last top skin until you finish wiring.

 

[cnpeters]

Thanks for the responses (though there was confusion from a couple posters that I was referring to the front edge of the canopy frame skin) on the bottom part of the skin. I did manage to find another reference to this a builder had, and he rolled the edge to better match the fuse side skin using a bag of shot or sand so as to avoid a crease. I may give that a try, as the skin is not riveted.

I had a similar issue at first, although not quite as much as yours. Anyhow, I found that the issue was simply that the skin needed to continue to curve to match the contour of the fuselage past where the canopy frame channels end. To deal with this I ended up just pre-bending some curvature into that area of the skin before riveting it to the frame, and that worked out pretty well. I used about a 1" diameter dowel and duct tape to do the bending, similar technique as used to roll the elevator and rudder leading edges. A couple of iterations of bending and test-fitting, and voila! If you haven't riveted your skin on yet, then I would recommend this method. If you have riveted it already, then maybe you could use seamers, but then you might end up with more of a straight bend rather than a matching smooth curve.