How do people bend their 3/4" pipe?

I dont know a friendly plummer and have looked and pipe benders and all the small ones only do 15mm SS max.

Only one i can find that will do 25mm is from screw fix and is a 12ton jack bender for 99quid.

Was hoping to find a cheap stand pipe bender that would work or possibly hire one.

Grelin,

I bought one of Scewfix's 12t pipe benders to enable me to make my exhaust system.

Rec'd it, tried it & sent it back.

Ended up buying mandrel bends from Custom Chrome.

Do you have a forge - he could probably do it for you.

ATB

Simon

I took a lump of 3" x 2" and cut the radius I wanted. Then clamped the pipe along 1 side and tried to bend the rest around the radius. It started kinking the pipe, so I cut some groves on the inner edge with an angle grinder. It then bent quite easily without kinks.

It does mean on the inner edge you see the crushed groves, but this will be covered with the aluminium that forms boot . The outer edge is completely smooth. (have alook at the pic)

It's free, fast and worth a quick try . .. .
Rescued attachment rearbars2.jpg

I'd also suggest finding a good local blacksmith/forge. Mine a good chap and is currently making my roll bar and adapting my silencer for me at the moment, he's quite cheap to, and good for steel/ali bits and bobs AND very cheap nuts and bolts. These local chaps can prove invaluable to a build.

hey gremlin,

A couple of guys at work used this stuff (I can't remember the name - a plumber might know) that you heat up and pour into the pipe and let it set. Then you can chuck it in your vice and give it a good seeing too with a hammer without risk of buckling or denting the pipe. When your finished you just heat it up and pour it out. Apparently turns the pipe into a solid bar?? If you want to know some more about it I'll dig up the guys and interogate them for you.

ATB
Chris

Drill a hole in a piece of 3"x2" big enough for the tube to go through, clamp it in the vice and bend the pipe a bit at a time, feeding it through. It works but you might need some practise pieces.

yours, Pete.

An old technique is to fill the pipe with sand...................


I wonder if an adaptation would be to block the pipe just prior to the bend point with paper or something similar. Mix some sand with summat like candle wax (lots more sand than wax) por it in and let it set. Then you can melt it out once finished.

If it dont matter if its in there for life, I wonder if something like sand and a weak fibreglass resin mix might do it.


In the 80's I had to install machinery in a volkswagen plant in germany. They cast things like blocks and manifolds using a kinda sandy clay mould thats put in the casting, then is dissolved out after the part is completed.

variation on a theme.

atb

steve

http://www.merlinmotorsport.co.uk/catalogue/workshop.htm




take a look at the bottom of the page.....

It might do it.

From what I gather the stuff looks like mercury and sets hard when cool, there's this spring you can use aswell, but don't know if they come in that size

Either that or order a pipe bender from screwfix, use it and send it back. My missus works for them and she says it happens a lot

Try an electricians pipe bender for conduit. Borrowed one from work, worked a treat! My whole chassis is tubular, look in the photos section, more to come.

I put this job off for ages and then one day decided i had to try, first attempt was with a hole in a block of wood and was unsuccessful. I then rumaged under the bench and found a peice of 6 inch dia steel bar about 1 inch thick . I gripped this in the vice resting on top of one end of the tube , then i gently bent the tube around it with no problems at all .The inside was slightly flatened but not enough to be noticable even before the sheet was fitted.To save the complication of working out the exact bend length i made two seperate bends and welded a straight length between the two.
Paul

quote:

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Originally posted by Gremlin
How do people bend their 3/4" pipe?

I dont know a friendly plummer and have looked and pipe benders and all the small ones only do 15mm SS max.

Only one i can find that will do 25mm is from screw fix and is a 12ton jack bender for 99quid.

Was hoping to find a cheap stand pipe bender that would work or possibly hire one.

---

A simple plumbers bender does the job
Rescued attachment Pipebend.jpg

Used sand to form my scuttle. Dried the sand in the microwave, and filled the tube with sand, using paper and wax as stoppers at both ends. Made a template using MDF and wooden blocks. Clamped the tube to one end of the MDF, and heated the tubing, bending it around the former. It worked but the MDF template was fairly BBQ'd! A description of how it's done is available at:

Sand Bending

Thanks for the replys.

Mark i have used a standard pipe bend for the rear top section as it creates a nice bend and almost exactly R3.0. How did you do the R2.0 bottom bend or was that with the same bender and just cut of a bit short?

Used the same bend, but capped it with 1" x 3mm flat bar for strength and continuity of curve.
Rescued attachment Lowerbend.jpg

Thanks mark i think i got what you mean but cant tell 100% from pic need to see from back really.

Have you cut your V bar a bit short and allowed the corner sections to bend around a bit further with W1/2 and RU1/2 welded to the corner sections rather than the ends of V or is that my imagination.

Does the sheet fold around the corner well or have you not made it that far yet?

[Edited on 16/4/03 by Gremlin]

I don't understand what you mean by V bar, but here is a bigger image of the rear end showing the radii
Rescued attachment RearEnd.jpg

The back bottom bar section V.

Not to worry though the last picture cleared everthing up and looks very good.

Many thanks for the help.