Thread: Pipe Bending Fail

Hi,
Im having the exact problem as in the OP, the only thing is my die is stamped 50mm but actually measures at 60mm, do you think i will be able to bend the walls of my die in 10mm by heating and hitting it?

Ive been thinking of getting some 5mm plate and shaping it to the walls of the die, then welding the plate in on both walls, does this sound like a good idea?

its driving me insane, i cant figure out why the die is 10mm wider than the size stamped on it.

any feedback would be awesome.
Thanks guys
james

Originally Posted by nethergate

its driving me insane, i cant figure out why the die is 10mm wider than the size stamped on it.

any feedback would be awesome.
Thanks guys
james

pipe is measured by the ID, not the OD... 2" water pipe has an OD nominally of 65mm, depending on wall thickness.. I know of 5 different wall thicknesses off hand which went by a colour code...

In order of increasing wall thickness..... Green -->> Yellow -->> Blue (standard water pipe) -->> Red -->> White

It gets confusing because metal metric conduit is measured by the OD not the ID...

Originally Posted by .RC.

pipe is measured by the ID, not the OD... 2" water pipe has an OD nominally of 65mm, depending on wall thickness.. I know of 5 different wall thicknesses off hand which went by a colour code...

In order of increasing wall thickness..... Green -->> Yellow -->> Blue (standard water pipe) -->> Red -->> White

It gets confusing because metal metric conduit is measured by the OD not the ID...

Thanks for the reply RC. Im using 48mm OD tubing, ive tried 2.5 and 5mm wall thickness with no great luck, Once i exceed a 25 degree bend it starts to buckle like in the OPs pic. If i use the die that is marked 1 1/2" which actually measures at 48mm it bends alot better, but starts to bulge out the top of the die and then goes to crap. I think the radious on this die is too small. I want to try and modify the die marked 2", either by heating it and trying to bring it in to 50mm, or by getting some 5mm plate and cutting it to the shape of the inside of the die, and welding that in so its the correct width.

any thoughts or better ideas?

hi would you like to lend some other dies to see if it works any better...

Originally Posted by nethergate

Thanks for the reply RC. Im using 48mm OD tubing, ive tried 2.5 and 5mm wall thickness with no great luck, Once i exceed a 25 degree bend it starts to buckle like in the OPs pic. If i use the die that is marked 1 1/2" which actually measures at 48mm it bends alot better, but starts to bulge out the top of the die and then goes to crap. I think the radious on this die is too small. I want to try and modify the die marked 2", either by heating it and trying to bring it in to 50mm, or by getting some 5mm plate and cutting it to the shape of the inside of the die, and welding that in so its the correct width.

any thoughts or better ideas?

Originally Posted by azzrock

hi would you like to lend some other dies to see if it works any better...

Hi azzrock. That might be very helpful, what suburb in Melbourne are you in? I will try and modify my dies first before i waste your time. Im finding it a bit hard to find replacement dies without buying a new bender.

Thanks again Azzrock, Yourock!

im from laverton what size do you whant to try. there maybe a few to choose from. at least 1 will be dawn or record

Hi Azzrock, i wouldnt mind trying a 50mm die, My tube is 48mm OD so i think it would be a good fit. what does dawn or record mean? As i said i wont waste your time though, i will try to modify mine first.

Thank you so much for your help
James

Dawn and Record are brand names.

you know there is an alloy that melts with boiling water. so mu melt it pour it in the it sets and bend away

thats what i ment the is a few diff brand benders to choose from.

Originally Posted by pipeclay

Dawn and Record are brand names.

Originally Posted by .RC.

It gets confusing because metal metric conduit is measured by the OD not the ID...

Same with the plastic pipe IIRC.

To the OP, so if I understand correctly, you bought a pipe bender new from a retailer here in Australia, yet the dies that were supplied with it are unsuitable for the pipe that's sold here. Is that correct?

Pete

hi pipe clay i just read the posts and relized you were not refering to my post

Originally Posted by Pete F

Same with the plastic pipe IIRC.

To the OP, so if I understand correctly, you bought a pipe bender new from a retailer here in Australia, yet the dies that were supplied with it are unsuitable for the pipe that's sold here. Is that correct?

Pete

You got it, but then I figured that would be the case - I could have sought a refund through the Fair Trading 'Not Fit for Purpose' clause but the only alternative is an order of 10x more expensive so tried to persist. I have fixed my 15nb and 20nb dies to give great bends so am still a long way in front of having bought a Dawn bender. My 25nb die gave acceptable bends from new and my 40nb die is close but needs a little more work.

On the Pipe vs Tube naming, keep in mind that all pipe is tube, but tube is not pipe.
ALL tube is SPECIFIED by it's OD, pipe is NAMED by its NOMINAL BORE (NB). 1 1/2" or 40 NB pipe has an OD of 48.26mm regardless of its wall thickness. 1 1/2" tube has an OD of 38.1mm regardless of its wall thickness.

Nethergate - your 48mm OD pipe should work in the 1 1/2 die, if it is not working then you will need to adjust/fix the die to make it work, alternatively if you can afford it then buy the correct Dawn die and it will work straight up. A single Dawn die will cost as much as a whole chinese pipe bender set though. From reading your post I get the feeling that you are trying to bend 48mm OD tube (40NB Pipe) in the 50NB die? This will never work and will result in a kinked pipe.

Have a look at this link here - Nominal Pipe Size - Wikipedia, the free encyclopedia this will give you the mm your dies should be measured to. If your dies are close to this (say +/- 0.25) then I wouldn't adjust them just get some med/sch 40 wall pipe and have at it!

i run a 40 ton pipe bender and use swadesir pipedies up to 90mmnb and 65x65 rhs.the dies are an interference fit on all pipe sizes and are called cathederal dies as this is the shape the minor side of the bend is pushed to as it is bent.if your dies are loose on the pipe then thin or ###### pipe will most likely fail at about 135 degrees.I have often loaded a piece of pipe next size down inside the bend length and bent the section down to aprox 70 degrees with out a fail,try it once before you spend money or waste time on modding your dies.16mm round rod inside 15nb,15nb in 20nb,20nb in 25nb etc.same goes for thin wall rhs,for example35mm inside 40mmx1.6 wall will give a great bend to 70 odd degrees.hope it will work for you.cheers,danny