Airdrome Airplanes Sopwith Pup Project

RAF56_Ball · 18 September 2009, 10:31 PM

The fun part about PC-10 is that you can have almost any thing from the dark green to the oxidized chocolate look. How? If you make a batch of dope according to the pigment formula, you can paint a sample swatch (like a 1 foot square piece shrunk on a wood frame), then expose it to sunlight. To make it more interesting, you cover it with a grid of say 3"X3" squares and uncover an additional square every 1-2 weeks, leaving this sample out in the elements. When you get to the last square, bring it in before you age it and look at what you get.
You could then pick any of the shades in between start and finish and have a legitimate "PC-10" with lots of aging character, or fresh out of the assembly hangar, heheheh.

RAF56_Ball · 6 October 2009, 09:45 PM

October 5, 2009 - Finished the wing ribs and trailing edges yesterday. I may add a stiffener to the wing tips, and have considered making wing tip skids (found in some of the very early Pups and a few of the trainer versions from what I can tell) that can be removed later. Protecting the tips cannot be a bad thing.

Center section was interesting. The plans call for making the TE using regular TE stock for the lateral pieces, then making up pieces of simple bent sheet to make the tapering pieces and the middle (essentially bending flat into channel). But as I looked at pictures, I just couldn't let go of the curved shape, so made some "quarter rounds" of half inch tubing (really only about 70-75 degree bent tubing), annealed a piece of leftover TE and opened the angle on it for the middle piece, bent the back edge of the center two ribs down and trimmed / notched them to fit. Then riveted everything together and called it done. Okay, so before I did that I had to adjust the tubing bends a little, but you get what I mean

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Tomorrow the control rods!

RobW · 7 October 2009, 05:34 AM

Quote:

Originally Posted by RAF56_Ball

Center section was interesting. The plans call for making the TE using regular TE stock for the lateral pieces, then making up pieces of simple bent sheet to make the tapering pieces and the middle (essentially bending flat into channel). But as I looked at pictures, I just couldn't let go of the curved shape, so made some "quarter rounds" of half inch tubing (really only about 70-75 degree bent tubing), annealed a piece of leftover TE and opened the angle on it for the middle piece, bent the back edge of the center two ribs down and trimmed / notched them to fit. Then riveted everything together and called it done. Okay, so before I did that I had to adjust the tubing bends a little, but you get what I mean

.
Tomorrow the control rods!

Glenn... I have no idea what you are talking about... Are you talking about the trailing edge? The cutout in the center section of the upper wing?

Maybe a picture would help...

Rob

RAF56_Ball · 8 October 2009, 11:37 AM

Look under "Wings" here, Rob. Yes, it was the centersection trailing edge cutout. I just couldn't think of the right phrase <G>.
http://www.ourgreatphysician.com/cfp..._files/Pup.htm

RAF56_Ball · 29 October 2009, 09:56 AM

Just about done with the wings. Will add a couple of strut opening panels and then dismount the wings for covering.
Next the fuselage front end. Just have a sheet of stainless steel for a firewall, the retaining ring, 6 tubes and 4 pieces of angle to add to finish all structures.

Finally will have the electrics, fuel system, covering and final color!

Well, okay, the nose bowl needs a bit of work too. But covering can proceed before that.

Bookmaker · 29 October 2009, 10:15 AM

Chip, what did you do about dihedral in the wings, or did you go flat?

Dale

RAF56_Ball · 29 October 2009, 09:44 PM

Quote:

Originally Posted by Bookmaker

Chip, what did you do about dihedral in the wings, or did you go flat?

Dale

Dale,
I went nuts (sorry, too easy a bad joke) and called Robert. While he is working on some castings that will work a lot like a 'eye'bolt hinge, he suggested using successively smaller tubes on the spars for the center section instead of a single sleave, thus allowing dihedral. Check this link for a picture, which is on the Assembly page, second picture from the left, top row:
http://www.ourgreatphysician.com/cfp...s/IMAG0032.jpg
It has worked very nicely. I calculated the lengths to give 3 degrees with a little clearance. It was easy when I used the Scientific mode on the calcualtor that comes with Windoze. I have the measurements at the airport if you or anyone else is interested.

Bookmaker · 30 October 2009, 06:04 AM

Does that allow a "slop" (bad term, but you get the idea) when fitting the outer wing panel spar tube over the stub, then the dihedral is set with the flying and landing wires?

Dale

RAF56_Ball · 30 October 2009, 11:04 PM

Yes it does, Dale, very nicely so.

When Robert gets around to the fittings, it will be even easier, since it will not only allow setting any dihedral, but be the point of wing atttachement / disasembly. I think he is developing a casting that he will then finish.

Have thought of milling them myself, but 2 inch round bar stock ain't cheap, and have only done some really simple pieces so far. We're talking 16 matching pieces. Yikes!

RAF56_Ball · 3 November 2009, 10:07 PM

Wings are now complete. next is to install the fuel and electric systems, oil tank, firewall and stringers, then cover this beast!