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Bending Box-Section
scootz - 13/10/11 at 07:14 PM

Can it be done without kinking?

HowardB - 13/10/11 at 07:19 PM

obvious questions, like,..

how big, how thick, and how far??

If the answer to any or all of those is ummm quite a bit, then the answer is generally no without special kit,....

hth

liam.mccaffrey - 13/10/11 at 07:20 PM

yes a tube bender, with a square section die will do it.

What size do you want to do? I am thinking of making a square die for my bender


[Edited on 13/10/11 by liam.mccaffrey]

scootz - 13/10/11 at 07:40 PM

I was thinking 25mm x 25mm x 1.5mm...

balidey - 13/10/11 at 07:50 PM

I have massive box full of that tube size with 90 deg bends, they are 'kinked' in a way where the inner and outer faces are formed in, the sides are flat. It looks pretty good and were all machine done. If you want some and they are any good to you I can post some up, they have about a foot of unbent section each end. You can weld them onto your box.

Or to try to bend it without kinking (much) and without a former, pack with DRY sand, seal both ends, heat and bend round a rough former.

MakeEverything - 13/10/11 at 08:25 PM

quote:
Originally posted by scootz
I was thinking 25mm x 25mm x 1.5mm...


I went too quick over a hump back bridge and bent the subframe of my 60 place laguna, so yes its possible.....

Confused but excited. - 13/10/11 at 08:56 PM

Didn't they used to fill it with lead first to stop kinking, bend it, then melt the lead out. This would be back in the days before hydraulic computerised mandril benders. Come to think, they probably used a low melting point alloy like Wood's metal.

MakeEverything - 13/10/11 at 09:22 PM

quote:
Originally posted by Confused but excited.
Didn't they used to fill it with lead first to stop kinking, bend it, then melt the lead out. This would be back in the days before hydraulic computerised mandril benders. Come to think, they probably used a low melting point alloy like Wood's metal.


It was kiln dried sand i think.

907 - 14/10/11 at 07:30 AM

In my experience the outer face of the bend tends to collapse in and becomes concave.

Not sure if you can see this in the photo of my o/s engine mount but this is 25 x 25 x 3mm wall.
I would think that in 1.5 wall this would be more pronounced.
I only needed 45 deg so not to bad. Had I bent it more I think it would have collapsed more.


25x25x3 box engine mount
25x25x3 box engine mount

Cheers,
Paul G

40inches - 14/10/11 at 07:49 AM

MK's have a couple of that are bent, the inside of the bend is collapsed inwards, no other way really.

Coolant pipe fixing
Coolant pipe fixing

MikeR - 14/10/11 at 06:13 PM

How much pressure is needed to bend 1" 1.6mm steel? I've often wondered how difficult it would be to make a former and bend it myself.

907 - 14/10/11 at 06:32 PM

quote:
Originally posted by MikeR
How much pressure is needed to bend 1" 1.6mm steel? I've often wondered how difficult it would be to make a former and bend it myself.



I used an 8 tonne jack to bend that 3mm wall s/s in the earlier pic, if that's any help.

Paul G

mad-butcher - 14/10/11 at 06:46 PM

quote:
Originally posted by MakeEverything
quote:
Originally posted by Confused but excited.
Didn't they used to fill it with lead first to stop kinking, bend it, then melt the lead out. This would be back in the days before hydraulic computerised mandril benders. Come to think, they probably used a low melting point alloy like Wood's metal.


It was kiln dried sand i think.

seen on "how it's made" forming brass bends for a trombone by filling with water and then freezing
tony

[Edited on 14/10/11 by mad-butcher]

40inches - 14/10/11 at 07:40 PM

The Locost way Linky