Sun Nov 5 2006

Tank attach brackets

I used the sander to round the profile of the tank attach bracket for the side where it attaches to the fuselage.

Then made the rough cuts to match the curvature of the inboard rib on the tank.

This sander rocks! It was definitely worth the money. It's saved me tons of time.

The tank attach bracket fits nicely into the rib.

Here's the pair of brackets. Schweet!

Kody was over and I got him to help me with some deburring. He's not used to using tools so he inadvertently put some notches in the inside edge of these doubler plates. I filed them out, but they're not completely round anymore. Ah well, it'll be fine.

I also deburred the plates for the capacitive fuel senders.

I drew circles up through the prepunched bolt holes in the spar to see where they would fall on the Z brackets. The were all right on center except for the inboard most bracket. This looks good, though. I drew an extra line along the flange of the bracket to show where the web is. Then I set a bolt in place right next to one of the circles so I could see how the hex head of the bolt would clear the web. Considering there's about a 1/16" radius at the web-to-flange transition, I don't think the bolt should be any closer than this.

I drilled one hole at the center (lengthwise) of each of the Z brackets and used it to cleco the brackets to the baffle. Then I lined up the lengthwise centerline of the Z brackets by sighting through the prepunched baffle holes. Once all that was lined up, I simply transfer drilled through the baffle into the Z brackets.

I marked a vertical centerline on the fuel filler flange and centered it up on the hole in the skin. It's held in place with duct tape on the back side.

After drilling the holes, I had to pop the cap in to see what it would look like. I'm glad I went with the upgraded fuel filler caps. The polished look is really nice.

Here's what it looks like from the inside after drilling all ten attach holes.

To set the tank on the spar with all the Z brackets attached meant that I needed to move the clecos around to the inside of the tank. So I uncleco-ed part of the skin...

...and moved the 1/8 clecos around to the inside of the tank. No the won't hold the tank up...

...when I set it on the spar. Here I've got a strap clamp pulling the tank to the spar to close up the gap between the tank skin and the main skin.

It's a reasonably tight fit now, but it also takes quite a bit of force to pull the tank down to close up the gap.

I match drilled all of the Z brackets by back drilling through the spar.