Anyone Out There Have The Tooling Required To Bend 1.625 Chromoly

Hi everyone. I would like to bend 1.625” (1 5/8) diameter, 049” chromoly. I need one bend at 45 degrees and I was hoping to have 3 or 4 tubes bent.
I know .049 thin wall is tough to bend. Let me know if you can help. Thanks.



I think it would be good to know what radius you want bent as well , but going to 45° on anything tighter than -9" radius us going to be tough without internal mandrel tooling. I have done 1.5" in .049 at 5.25" radius die and after about 28-30° it starts necking or rippling pretty bad. anything past that it collapses. It usually took 2-3 tubes and I get a good one, still with plenty of flattening on outside of the bend

Joe at cobra should have a 1.625 die , but your only going to get to around 25° after 10° springback , beacuse the 9" die can go to 35° max.

I would see if you have a local bending house that has internal mandrel machine for that tubing size and a radius you can use. and the internal mandrel is specific to wall thickness. only doing a few will be quite expensive most likely too even if they have the tooling

Not much help but some feedback , from my adventures in tube bending



Andrew thanks for your reply. I have had my fair share of bending adventures as well. I’m good with a 9” radius but I don’t think the Cobra bender will work for me if I can’t achieve a 45 degree bend. I sent Cobra an email but it looks like you answered my question.
I was looking at the JD2 model 32 bender. They make a 1.625” die with 7.5” radius although the specs say minimum .083” wall. I wondering if I could get away with bending .049” wall with it?

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it might be possible , but again I think if you were staying in the lower degrees you can get away with it maybe , in .049 very likely will have large amount of flattening and necking , if your okay with that . If you have the Jd2 bender already , the nice thing about it is the dies aren’t crazy expensive , but not cheap if it doesn’t work. You might give them a call and ask if they would test bend , if you sent them a section of tubing. That way you know what the result would be. I have done that with the ercolina usa guys , as I wasn’t buying a 1000$ die set for it not to work , on a tube size I wanted to do. the test were no good , so I moved on.

That’s a great idea. I’m going to send JD2 an email and ask for their thoughts. Thanks.


Hey Fernando, we learned to braze together.

I’m not sure how the price compares on the JD2 versus Rogue Fabrications but I’ve found the Rogue guys to be helpful with questions like this via email and I think they’ll do a test bend for a couple bucks as well.

I’d love to know what you’re using this bent tube for.


Hi Travis! Great times with Doug Fattic in Niles MI. I was watching the videos we took the other day. Still helpful all these years later. I’ve jumped into tig welding bikes instead of fillet brazing a few years ago.
I’ve never heard of Rogue Fabrications, I’ll definitely check them, thanks for that.
I am making a cargo bike like the latest short version of the Omnium cargo bike. Trying to keep the overall length of the cargo bike the same size as a regular bicycle.