Correct bend radius for sheet aluminum?

[chinch]

I've just purchased a 3-in-1 roller/press brake/shear, and in line with comments made in this forum some months ago, 90 degree bends are very sharp, and I suspect, not appropriate for sheet aluminum in an aircraft environment. I intend to get the fingers machined to a more appropriate radius, but can anyone please tell me what that would be?

Thanks in advance
Chris

[az_gila]

...is on-line in PDF form...

http://rgl.faa.gov/Regulatory_and_Gu...E/CONTENTS.pdf

The metal chapter (4) with the numbers you ask for is here on page 14 -

http://rgl.faa.gov/Regulatory_and_Gu...apter%2004.pdf

[rocketbob]

Originally Posted by chinch

I've just purchased a 3-in-1 roller/press brake/shear, and in line with comments made in this forum some months ago, 90 degree bends are very sharp, and I suspect, not appropriate for sheet aluminum in an aircraft environment. I intend to get the fingers machined to a more appropriate radius, but can anyone please tell me what that would be?

Thanks in advance
Chris

I've got one of the same machines. Easiest way to get a 1/16" radius on the fingers is to weld a 1/8" rod to the ends of the fingers which is what I did. I also cleaned up the lower die with a die grinder and 2" scotchbrite wheel.

[chinch]

Thanks everyone for the excellent feedback and leads.

Did I say how great this forum is?

Chris