[13bute]

hi , do anyone know of some free software or a name of a iphone app i can buy
to calculate bends on some 9.5 mm tube i have to bend , i found one that was perfect ( bend it )used on roll cages but it only goes down to 2 inch on the radius . i have 6 bends on each part and all different size so just wont the easy way out

cheers andy

[txcncman]

Most bend reduction calculations are developed "in house" for particular materials, applications, and die sets. I have never found a chart or "calculator" that covers everything. You can probably extrapolate the information you need from the information you already have.

[neilw20]

Whether flat or tubing some metal is 'gained' in the bend.
Do a test piece. Start with exactly some dimension L.
Do a 90 degree bend of the required radius. Measure each leg L1 and L2.
L1 + L2 - L = the amount gained, given the bending conditions and the material.
Once you know the amount gained for a given setup/material just apply that to the job.
Often with different batches of material you will get different results so a test piece for each batch is often needed. A slightly different temper will change things.
As you are doing a roll cage, I guess it will all be the same batch!

That's what I picked up 35+ years ago in aircraft sheetmetal course and it is stuck in my brain still. It was all manual stuff then. You made your own chart for the material and tooling you had.