Hi all,
Can anyone explain the logic behind this bend?
It seems strange if the flatten state of the part should be shorter? - it is certainly not what happens in real life.
Bend:
Unbend:
Please see attached part file and pdf drawing.
Hi all,
Can anyone explain the logic behind this bend?
It seems strange if the flatten state of the part should be shorter? - it is certainly not what happens in real life.
Bend:
Unbend:
Please see attached part file and pdf drawing.
Seems correct to me. Do some research on what a k-factor is since that will explain it better than I can. Typically, each bend will stretch the metal just a bit so this has to be compensated for when estimating what the flat pattern of a formed part will look like.
Victor, it makes perfect sense and is true in the real world.
Your 90 dimension is the straight portion + inside corner radii + 1 material thickness.
The neutral bend line is ~1/3 of material thickness from the inside bend radii.
BTW, you "should" only dimension the Inside of any bend as there is material thinning and the outside radii is almost always;larger than the mathematical (inside radii + material thickness) (in the real world the outside radii isn't a true radii)
I hope this helps.
The only problem you have is, you can't really bend it that way.
Such a short bend require longer material and cut it off after bend.
As others have said, it's actually what does happen and is based on K-factor. Below is guestimation that is close without doing any real calcs. If the material bend line is at what I show as construction line this works out pretty close. The line length on the top/bent part is something like 89.91. The position of the bend line changes depending on all sorts of factors...which as others have stated has to do with K-Factor.
As has been pointed out, this cannot be formed as shown. Our fabrication guys would be fuming if I sent this thru. Hopefully you already knew that.
Thanks for the input
Seems correct to me. Do some research on what a k-factor is since that will explain it better than I can. Typically, each bend will stretch the metal just a bit so this has to be compensated for when estimating what the flat pattern of a formed part will look like.