Pipe bending

I'm getting close to finisdhing my Polly Engineering O&K "Suzanne", and need to bend the annealed copper pipes for the water and oil feeds. The pipe is ~5mm diameter, and I can only find benders down to 1/4". Any suggestions?

Thanks.

Mike

Bending springs, i think Chronos do them. They fit OUTSIDE the tube -at least that's how I use them.

Neil

Hi Mike,

If you want to buy one may be this will be OK? You can of course build your own tube bender. You may have to fill the tubes with salt or something before bending. This will reduce the chance of the pipe collapsing when bending. Place the tube in water after bending to dissolve the salt.

Thor

Can one still get Woods Metal or Cerrobend ?

Roy

Alex Tiranti do Woods Metal

J

Chronos do a tube bender the same as the HF item in Thor's link.

I have one and find it works well providing I fill the tube before bending to avoid it collapsing. I use fine dry sand and have found that crimping a couple of mm at the ends of the tube retains it OK.

Jim

Hello Thor,

The link to Harbor Freight is great only problem is postage to this part of the world is humongous.

I can't find the plans for the small pipe bender listed in the the link you gave, guess the picture says it all, but wondering if you by chance had a copy of the plans.

Regards

Brian

Brian,

Original plan on web is here , neat little bender!

Andy

Thanks Andy,

That is a great collection of little bits and pieces.

Brian

Hi Brian,

sorry I forgot to link to the plan, glad Andy solved that. Here's another plan for another tube bender. Roy, if you can get Woods metal that works well for filling the tubes before bending.

Thor

Look on E-bay for CERROBEND - I have seen it there sometimes

**LINK**

12 quid a kilo - seems cheap!

BobH

Fill tube with fine dry sand and plug both ends and heat tube where bend is required.

You could also machine a groove to suit the tube and bend radius in a piece of round bar and use this as a former for bending the heated tube. Heat the former as well as the tube so heat is not sucked out while bending.

So as you are aware there is a problem with Colin Binnie's bender design in that you can't pull back both arms parallel to allow feeding in a straight length of tube first - I'd built it before the penny dropped! It needs redesigning with the pivot offset from the centre line of one arm/aligned with the centre line of the other so the arms fold back flat against each other. This might not be important to you depending on what form your pipework takes; otherwise there's a lot going for the simple construction.

Robin

Cerro are still in business, I've driven past them: **LINK**

**LINK**

But Cerrobend is now made by CS Alloys and imaginatively called "CS Alloys Bend" LOL!

http://www.csalloys.com/products-cerrobend-alloy.html

Neil

Edited By Stub Mandrel on 16/06/2013 17:05:44

When I was an apprentice, we used to bend 2" and 3" thin walled stainless tube filled with ROSIN which I believe is a product of Pine Tar. Once the tubes were bent on a hydraulic tube bender, a steel ball was 'hammered' down the tube by placing a slightly smaller ball or two behind it and shaking them down. Rosin can be found in musical instrument shops for treating violin bow strings. Once heated, it melts and flows like syrup, going hard when cold.

For smaller tubes, we used CERROBEND. A bit of a laugh to saw a teaspoon in half and join the two halves with a bit of cerrobend, and slip them into the mug on the tea trolley. Sit back and wait for the rude remarks !! Life were fun then.

Mike,

I came away from the "Hobbies" shop in Norfolk yesterday with a 2013 catalogue.

In it were a set of pipe/tube bending springs (external type).

They are in sets of five and will bend from 3/16" O.D. down to 1/16" O.D.

Price for the set is £3.85

Their website is: www.alwayshobbies.com.

As most of us oldies know, Hobbies have been going for many, many years and the Hobbies annual used to be a longed for birthday or Christmas present.

Len.

Many thanks everyone. I have purchased the Chronos bending toll, and a set of pipe bending sprinmgs from the same source. Practice on some brass tube has generated perfectly bent pipe. Today it will be the copper pipes!