Bend Deduction Headache with Sheet Metal

[sltyler]

Hello, I'm trying to customize Inventor to create flat panel projections that are accurate to the press brake in my shop. However, I seem to be missing some piece of the puzzle when trying to figure out Inventor's bend deduction formula.

We bent in half an 11gauge 6" piece of 6061 aluminum at 90 degrees. The die creates an inner radius of 0.16". The resulting legs were 3 3/32" and 3 3/32". The bend deduction would be 3/16". To confirm, we took another piece at 5 3/16" and bent it up 90. The resulting legs were 3" each.

However, Inventor, using the default bend deduction formula, flat panels a model of this piece with a total length of 5.962". The 0.1492" difference really adds up after a few bends!

So, how can I modify Inventor for this need? Sorry if this seems like a condeluded question for a (possibly) simple solution or if this has been posed before (I couldn't find the solution). Any help is appreciated. Thanks in advance.

[rdyson · Accepted solution]

First I assume a typo, the flat should say 5 13/16 not 5 3/16

I just created a sample (see attached) of 11 ga Alum with 3 in legs and .16 bend radius

It's flat length is 5.813 using standard K-Factor of .44

[blair]

this might help.

[sltyler]

Thanks for the quick response. Works like a charm!