cabin frame struggle

jimgreen · #1 04-28-2008, 11:09 AM

Anyone with advice on how to straighten the flanges on the cabin frames?
Mine are not bent to 90 degrees and won't work out of the box.

DGlaeser · #2 04-28-2008, 11:55 AM

Your favorite pliers or crescent wrench (with some protection), or seamer will work...
Don't expect many (any) sheet metal flanges to work 'out of the box'. It's sheet metal - adjust as necessary

jimgreen · #3 04-28-2008, 12:13 PM

Thanks for the reply. What has stumped me on this is how to adjust the flanges on the curved section, specially the inside curve. The material would need to be stretched to make the 90 deg. without distorting the frame "out of flat".

Brantel · #4 04-28-2008, 12:32 PM

I doubt you will ever get these perfectly 90° but I doubt they need to be. How bad are they?

Mine were some out as well but after it was all riveted together, you would never know it.

Call Van's if in doubt.....

DGlaeser · #5 04-28-2008, 12:37 PM

The flanges have to 'shrink' to bend around the curves. The few degrees you need to (un)bend them should not be a problem. They are sheet metal, not machined parts!

Auburntsts · #6 04-28-2008, 01:09 PM

Have you tried clecoing any of the skins to the frames yet? When I was first putting my tailcone together, I was looking at the frames like they were ribs and wondering how to get them flat and with flanges at 90 degrees. Turns out the geometry was such that they were pretty close to perfect out of the box (they aren't supposed to be flat), just it didn't seem that way laying on the table--they looked warped to me. However, once installed all I had to do was flute where directed (on the -10 you flute every tab with 2 holes) and all holes in the frames and skins aligned with minimal fussing around. I didn't have to seam a single tab.

jimgreen · #7 04-28-2008, 02:59 PM

Thanks for the replies.
Brian, I did call Van's. Joe was pretty noncommital and didn't have any helpful suggestions. There is up to 1/32" of air between the frame(631A) and the lower strap(631B) - may be more in some spot on the inside curve. I think I can reduce some of that when I radius the edge of the strap.
I've tried flanging a little and it's definitely going to twist the frame. It would be nice to have heavy duty rollers similar to the edge roller we use on the sheet edges. That could stretch the metal of the inner flaange to allow proper flange adjustments.
BTW yours looks pretty **** good in the picture!
Dennis. I think the outer flange has to shrink for a flange without fluting, but the inner flange has to stretch. No?