More fun with the electronics bay. I've used up something like 72 square inches of lite ply to get a hatch cover that uses about 18 -- the rest are all false starts, screwups, and the like.
But, I now have all the electronic bits I need to support a TUT all tucked away into the outboard wing where they'll be out of the way of the control system and where the weight might do some good. Much of the agony was trying to make a super-duper one size fits all box that would attach with the hatch cover and hold TUT, battery, and regulator. I finally ended up with a hatch cover that holds the TUT (something needs to hold the TUT rigidly, or the accelerometer and gyro readings won't make sense), and I just stuffed the rest of the electronics in between the wing ribs. Which is what I should have done from the start...
I did find a nifty way to make a hatch cover that you don't have to pry out with your fingernails. The hatch cover will need to come off any time the TUT is being talked to, or when I need to take the battery out for recharging; I didn't want to mar up my finish. So I put a magnet on the TUT carrier and a magnet in the hatch cover, oriented so they oppose one another. As long as the hatch cover isn't stuck it floats right out of the hole.
The last picture in the series shows the magnets being glued in. I routed holes in the two bits of plywood, and epoxied the magnets in. I always get magnets and such backwards from how I want, so I was careful in how I jigged this up. I started with a magnet underneath the TUT carrier. That forced the magnet in the TUT carrier to orient with the first magnet, and held it at the bottom of its hole. It's embedded in epoxy. Then there was a piece of waxed paper, with the plywood for the hatch cover laid out upside down on top. This means that the magnet in the hatch cover will attract when the hatch cover is upside down -- and repel when it's right side up. Finally, I topped the whole thing off with more waxed paper, a scrap of wood, and a magnet to hold the wood down and give me a nice flat surface.
If you're flying in the Pacific Northwest late this year, you'll know my plane -- it'll be the one with a dot of iron filings on the outboard wing, just outside of the fuselage.