When we left off last time, I was dealing with some weird gap appearances around the pin covers. First step for dealing with this was to work on sanding the cowl counters to match the dummy pin covers. I put electrical tape on them to save them from sanding – not for cosmetic reasons, since they’re throwaways, but really just because I only want to sand the cowl, not them – installed them, and went to town. At first I was trying to use a small block, but I was finding it really awkward. Instead, I decided to break out my oscillating multitool and use it with a 60-grit sanding pad. This worked out really nicely; I was able to carefully localize the sanding to just outside the covers, and ease the material off nicely. Doing this did leave a bit of a bug just outside where I was sanding, but the block I was using before worked well for cleaning up that contour.
With the dummy covers showing a nice consistent contour all around, I swapped in the real covers, expecting things to look much better, Well, they did look better, but still not like I was expecting. For example, the right-side cover still had a really prominent overhang going on in the upper rear area:
I find this mildly annoying. The idea of this pin cover kit is that you do all the fitting with the dummy covers, then swap in the real ones, which are slightly smaller and thus allow for a paint gap. The implication here would seem to be that all the contours should be the same, but my experience isn’t showing that.
Another reason for using the dummy covers is to avoid marring the real ones, but at this point I decided there wasn’t much to do but to instal the real covers and use those as a visual guide for refining the contours even more. As before, I covered them with electrical tape for protection, and went to town with the oscillating tool again. This time, of course, I was really careful working near the covers.
In the end, I got things to a point where I was satisfied with the overall fit. It’s not picture-perfect, but at some point I need to calm down here or I’m going to end up sanding this cowl on a daily basis until I die of old age.
Similarly, I’m still not 100% pleased with the fit when viewed from the side. Again, given how the dummy covers are supposed to be used for fitting, I’d expect to have a nice even gap all around, but instead things are definitely uneven. But I don’t really have any desire to go nuts here trying to make things perfect. At least not right now…who knows what dumb idea I might given a few days to mull over it
Anyway, here’s the side view:
Also shown above, but maybe less obvious, is some more fiberglass work I did here. When I originally opened up the cover backing to allow access for the pins, I took the opening all the way to the edge of the pin cover opening. The results, when the real covers were installed, were obvious openings at the forward/rear ends of the cover. I guess they might not have really been noticeable in the real world, but they were bugging me…so I decided to fill them in.
To do that, I did the usual scarf-joint dance: sanding the existing glass to a knife edge, then laying up some more small strips at the ends of the openings, with the dummy covers in place to keep things neat. Then, the following morning, I got to split the cowl halves again and do some more cleanup. Now those inner flanges extend a bit all around, and provide a nice backing for the covers:
Back to this evening, I finished things off by fitting the lower cowl back on the plane. I think my next move is to take the temporary pins I’ve been using and get them trimmed to length and formed for actual usage. The big question in my mind is what I want to do with the forward ends. These need to project past the forward extent of the hinges, and I need to be able to reach in with something like needle nose pliers to grab and extract them. Not sure if I want to just put a little 90° bend up here, or bend a little grab ring, or what. I think this calls for some research into what other people are doing.