Question on bender

Hello all,
I want to make a bender for bending flat stock into circles. I want three wide rollers to do the bending. I will bend cold. I plan on
making something similar to Ernie's bender with the steering wheel on the drive wheel. I want the rollers to be about 8" wide (flat) and about 2" diameter. Ok, all that said, I have a couple of problems.
Problem one: I planned on using scrap hydraulic rams as the rollers but have no lathe and do not have a method of turning the ends down small enough to fit bearings. Does anyone have any suggestions on how to do this without taking it to a machine shop?
Second question: I would like to use 1.5" bearings but they are 85 dollars at Enco and some places are close in price. I need six of them. How far would be feasible to turn the rollers down and still have a bender capable of bending 3.16" flat stock (not on edge)? If I can go down to about 3/4" the bearings get a LOT cheaper.
As always the help and advise will be appreciated.
Thanks,
Bob
www.warnerknives.com www.serviceusa1.com
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Buy a metal lathe. Other than tools which cost considerably more, I don't think you're going to get an acceptable job without using one, whether it's one you buy or one you pay someone else to run.

How much volume will you be bending? Consider bronze instead of roller or ball bearings (I assume, to get the price that high), which should drastically cut your cost, and also might allow using 2" bearings directly, so you can skip the lathe. I see a low of $5.55 and a high of $23 or so for oil impregnated bronze bushings in 2 inch diameter from MSC. Shop where you like, prices should be similar. There's also a steel/lead/teflon composite that might work at a similar price level. I have some of each working hard in my backhoe, and I'm reasonably certain that it can bend 3/16ths flat stock 8" wide without making an effort ;^)
Using the full diameter also means that you have the largest bearing area, so the lowest pressure on the bearings, and no stress concentration where you've cut down the rollers.
--
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Why not just buy steel heavy wall tube, and press your bearings in on the ends?

Try an actual bearing supplier. 1.5" bearings should cost about $20 - $25 each.

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