So I decided today that I couldn’t stand working on the finishing work for the whole day. I do like finishing because things start to look pretty, it is relatively mindless work, and it shows the fruits of labor years worth of labor. But then again, it is tedious and hours on end of sanding is physically grueling. Notice the love hate relationship.
Anyways, Greg was here bright and early today. Which was good, after last night’s late night in the shop, I wouldn’t have gone out at all. So we started working on the forward bulkhead.
Recall that when rolling the fuselage back right side up I damaged a forward bulkhead. This particular bulkhead was also undersized since I have the long nose modification. So we decided to cut it out and remake it.
We did leave little tabs of the original bulkhead in place. We hollowed out the original foam, and now we have little holders on each end to locate the new bulkhead.
We made the bulkhead out of leftover blue wing foam since it is similar density and has better peel strength properties. To do this we clamped my Hotwire saw to the workbench and used the setup like a resawing machine. The end result was a piece of foam the same thickness as the original bulkhead foam core. You can see it was shaped to the new contours and temporarily put in place. It will be microed into position and glassed when to top forward deck is bonded on.
While all of this was in process, Greg and I worked on defining the shape of the canard intersection fairing. James Redmon reminded me that since I don’t know the displacement of the elevators at race speeds, my fairing will be temporary and require rework. But here you can see the outline of
What we are working for.
Lastly, as we were working on the fairing we started thinking about the elevator torque tube seals. The plans don’t address this. But the elevator torque tube hinge point is not in the center of the tube, so as the torque tube rotates it also translates. So the hole through the side of the fuselage has to be elongated. This is all well and good, except I live in Minnesota and that amount of hole in the side of re fuselage can result in a bit more than a minor draft. So we have to seal it. Here you can see the big hole.
I decided long ago that I liked Terry Schubert’s solution to this. Basically he adds discs to the torque tubes that are offset. They look like cam lobes, and are centered on the hinge point. This allows these discs to only rotate. Not translate. See CSA newsletter number 99 for the details.
I started working on this process, and ran out of energy. Staying up late last night was not the way to maximize productivity today. Well, there is always the next work session. Once those are done we can get the canard intersection and elevator root fairings done!