I know pipe benders don't bend tube very well, because pipe benders are concerned with ID, and tube is measure in OD.

Would it not be possible to use a pipe die, add a piece of sheet metal (of a calculated thickness) between the die and the tube to make up the difference in size, and get better, deformed free bends?


*I've never had a chance to use either a pipe or tube bender, so this idea might be bananas

why not hire a pipe bender its about £3 a day or £15 a week .

quote:

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Originally posted by thunderace
why not hire a pipe bender its about £3 a day or £15 a week .

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Dave surely you need a pipe bender for your roll bar.

John

err No!

as Jammy Basturd says... a Pipe bender is for Pipe which is measured by ID and a Tube bender is for Tube which is measured by OD. the dies for a Pipe bender do not fit tube properly (and vice versa)

Basically Pipe and Tube are very different animals.....

whimps
Rescued attachment bend bar.jpg

He He!

I'd like to see him try that with my 1 3/4" 3mm wall CDS tube

As you can see from the above image, my teeth are beginning to hurt now, so I'd rather switch to a manual or hydro bender of sorts!

Also, does anyone know why a pipe bender is so much cheaper than a tube bender? They are essentially the same tool, only with the dies made to different sizes?!

Cant say ive looked into this, or given it any real thought.
- However can you not just get a diffrent die thats the right size?
- Or even machine a correct sized die from an undersized one. Or make one, or somthing.

Otherwise i have not reason why using some sheetsteel to line and slightly oversized die to reduce the size wouldnt work. But again, ive not given it much thought, or actaully done it.


Daniel

Try and search for a local Exhaust in your area...

Steve

Martin Keenan has approx £20k's worth of tube bender.... would he not bend your tube for you for a few quid?

Cheers,
James

I'd prefer to have the tool at my disposal really. I know the old phrase about measure twice and cut once, but if any bends were slightly out, or completely wrong, is then further hassle to get more tube in, work out the bends, get someone to bend it, then deliver it...

For what I'm doing, which is all pretty much bespoke stuff, its just easier to be able to do it myself.

Speedy hire has tube benders

no the only have pipe benders.....

ratchet bender

Those all claim to be pipe benders...

And when you click on ratchet bender it says no results found...

At the end of the day, renting something once will almost pay to buy a pipe bender, which brings me back to my original question...


Anyone have a pipe bender they can try it with? Or has anyone tried it before? Or can anyone give a reason why it wouldn't work before I buy a pipe bender?

Jammy I have used a Machine Mart hydraulic pipe bender to bend 60mm tube in the way you mention, it just so happened in my case a 50mm pipe die fitted a 60mm tube pretty good.

The problem with these pipe benders is nothing to do with them being for pipes, if you had tube dies that fitted perfectly you would still have tube collapse unless it's very heavy wall because the pipe/tube is not supported all the way round

I bought one of these
http://www.pro-tools.com/105.htm
if your not to far away I can bend 25mm, 30mm, 1.5", 2" for you

Cheers
David

[Edited on 6/2/08 by Minicooper]

[Edited on 6/2/08 by Minicooper]

unfortunatley the difference between pipe and tube isn't just the way its is measured it is the thickness of the walls, thats why you can use these cheap machines only on pipe, and why you need to use a proper mandrel bender on tubing which supports the insides of the tube and stops it collapsing during bending.

I bought a pipe bender from ebay hoping that I might be able to make a manifold with it and was pretty dissapointed and ended up buying a welder and some pre-bent (mandrel) bends instead.

I have heard of thin wall tube being bent without collapse by filling the tube with sand and then welding up each end and then applying heat whilst bending, perhaps you could try this?

Alternatively find some thicker walled material.

HTH
Dan

Jammy,
I can bend thin walled tube perfectly with this

http://www.pro-tools.com/105.htm
if your not to far away I can bend 25mm, 30mm, 1.5", 2" if you get stuck

Cheers
David

Hi David....R1Mini?

Unfortunately I'm in Kent, so easily an hour or two from you...

I've considered taking the plunge on one of those pro-tools benders, especially with such a strong pound at the moment, but I still reckon its going to end up costing me about £500 once its all imported, and at the moment I just can't afford that.

Might just strike the comprimise between using a pipe bender and thicker walled tube, and if my idea about using some sheet metal makes the bends any better then I'll be happy!

R1mini that's me,

The tube bender is more like a grand by the time you add carriage and vat and import duties and a few die sets.

I did some experiments with scrap pipe using the cheap hydraulic Machine Mart pipe bender and the wall thickness has to be around 4mm to stop it collapsing, it will still deform though

Cheers
David

bent all the cage tube for my grasser with a pipe bender (using the right size TUBE dies in it though) without distortion or kinking, and that was 2.5mm wall....................................................................

apologies for photo quality but:

45mm x 2.5mm CDS tube for main roll hoop



main hoop

bender used to do the job:



tube bender

operation that MUST be done first:



tube anneal

the annealing softens the tube, then the bending re-work hardens it again.

The reason it kinks and pipe does not is that pipe is soft and cold finished tube, unless bought in the annealed condition (which then doesn't technically meet MSA rules) is not.