View Single Post
  #1  
Old 07-26-2016, 05:28 PM
twoslo4five0's Avatar
twoslo4five0 twoslo4five0 is offline
Junior Fabricator
 
Join Date: Jul 2016
Posts: 7
Critique my tube bender design, be gentle my first post

Hello all, thanks for having me on the OFN! Some of you may see me post on several other forums but I finally made it over!

Ok, so I've been bending tube with a rogue fab alpha for a few years. I mostly bend 1.25 SCH 40 or 1.25 .120 wall DOM. Both of which I bend out the same die. As of recently I've been wanting to expand into some different size martial. I really didn't want to buy any more dies, or invest any more into the alpha so I put it up for sale and sold it for 500 (not bad as I have around 700 or so in it new)

This time around I really wanted to go with full hydraulic and not air over hydraulic. This decision isn't cheap as most know, hence why most people don't go this route. This is the start of my build, it will take me some time to complete but I will update it as I go along.

I did a pile of research on benders. I ran across a 1.25 SCH 40 pro tools 105 die semi local to me for 225 bucks so I picked it up. Knowing then I was going to run PT dies I could either go with 3 options. Pro tools, JMR or pro bender. JMR stood out as the obvious choice to me after contacting troy at swag off road and picking his brain. Plus the price was right 249 + 51 dollars shipping on just the bender itself. This is the race line with no handle attachment and you must order it directly from JMR.

Untitled by Jay Gordon, on Flickr

Untitled by Jay Gordon, on Flickr


The JMR bender has bushing that hold the arms together when changing dies and the material is 4130 HT 5/8s thick arms. by saving 100 bucks over PT the only thing you don't get is powder coat.

Next I needed to figure out a way to mount it. I wanted a tube roller as well and stumbled into these plans on eBay. 38 pages of detail, definitely worth the 10 bucks. I will have to modify them a bit but its a great start

http://www.ebay.com/itm/Air-hydrauli...Fba6GZaU1ce5EQ

I had a ram that came off a rockwell axle that was totally the wrong ram for the axle. In came that. its a 2.5, 20 inch, 1.5 bore ram. Should be fine for me as I'm not bending any .250 wall or larger.

Untitled by Jay Gordon, on Flickr

After that it was time to find a pump. I was looking at one at northern that was 450 bucks and just thought there had to be another option. After shopping around on ebay and using this calculator

http://www.baumhydraulics.com/calculators/cyl_speed.htm

I settled on this pump. http://www.eaton.com/ecm/groups/publ...t/pll_1222.pdf

Untitled by Jay Gordon, on Flickr

Specs are

220v single phase 1 HP motor
2 stage pump
5000 PSI limit
2.5 GPM
2.5 GPM @899 or less PSI
.5 GPM @ 900 or better PSI

As you can see the GPM really drops off after 900 PSI. I couldn't find the exact pressure it took to bend .120 wall dom but even at .5 GPM the cylinder will extend to full stroke in 30-40 second which is plenty fast. At 2.5 GPM retraction for repining should be quick and thats really where I wanted to speed. I should be able to bend to 35-40 degrees before repining which is fine by me.

Everything you see in the picture came with the pump. Its was 240 bucks shipped on eBay.

I also bought all the steel and fasteners with was another 121 bucks. I ordered my 4-way valve off eBay as well which was 94 bucks shipped. Everything is brand new, not used. My steel should be in next week and I can get to building. Trying to stay with the cheap aspect of things, I'm into this so far for 982 bucks. I have a connection on hoses so hopefully I will only be in another 100 past that. To build the tube roller (which will come later) my rough math is 714 bucks. Thats for the harbor freight roller and pipe threader plus all the swag add ons. I fairly certain that Im going to be done with this whole project for 2k or less, which is the cost of most hydraulic benders without shipping. I will have both a roller and bender for that price. Stay tuned for more updates.


Add another 60.55 in electrical cord, a 220v switch and a male 220v plug. I went with 10/3 for the cord, though I really only need 12/3 as the motor only pulls 15 amps. I ordered 25' of cord that I can jump off my welder kart as I have an accessory outlet to plug into. If you haven't seen my welder kart, here ya go

Untitled by Jay Gordon, on Flickr

Also the 4 way valve showed up this afternoon.

Untitled by Jay Gordon, on Flickr

Last edited by twoslo4five0; 07-26-2016 at 05:32 PM.
Reply With Quote