90 degree radius bender

[Scratch]

Any ideas on type of machine what I need to make this type of bend in 3/16" steel. I would prefer to make it myself.

[Verboten]

Hello!

I would (and do) use a Hydraulic Press Brake for this type of bend. I'm not sure if you want to just make the part yourself or the part and the machine/tooling to make it. A simple Brake can be made for common H-frame presses. If my artwork below turns out it will give you some idea about what one looks like in profile. On the part that attatches to the ram of the press the "I"s represent a solid piece of bar or plate (say 1"x4") welded to a piece of solid round stock. The piece that is sitting on the table represents two pieces of solid round stock welded to a plate. Use mild steel for all. The size of the round stock that you use and the distance between the two on the table will determine the radius of the bend and the force needed. You will find that the round stock that you will need has a smaller radius than that of the bend.



--Ram--
....I....
....I....
....0....
..........
_0__0_
-Table-

I feel that I have to mention-
Building and using press tooling as with many aspects of metal work can be very dangerous - make your own decisions regarding your own safety.

-Jason

[Mcgyver]

how many? if its any volume, like jason says quick work with a hydralic press and some home made dies (not hard to do)

for small quantities I'd clamp the work and a suitable dia piece of steel in the vice (ends up forming the inside radius), get rgw work red hot with the torch along the bend. have some vice grips an thicker bar, say 1x.5 across the top (this will help keep the bend even and provide some leverage) - apply force there and it will be easy to bend leaving a nicely form radius.

[Scratch]

I'm thinking about making them to sell so hopefully in high volumes. I've found a local guy that has a press brake set up to do 28" wide by 1/4" thick. That's about what I want. He's using a 40 ton ram and says it's no problem. I haven't seen it yet but if anybody has any pics of something like this, preferably homebuilt... I'd like to get some other ideas.

[Mcgyver]

its a simple, albeit heavy duty, home build. search here and the home shop machinists bbs you'll see some nice write ups on home builds. here's a simple hydraulic press - you can make them manual or motorized.

http://www.eagleequip.com/Merchant2/...SU5220_325.jpg

challenge for making one of big tonnage is finding a big enough dia cylinder at a reasonable cost, ie 5-6". I don't know how many tons you need, depends on length etc, machinery's handbook probably will tell you, but you'd want to overbuild it imo.

here's what i think of as a press brake

http://www.e-ci.com/products/brakes_maxform.html

the hydraulic is slower and usually you don't see them much bigger than 40 or 50 tons. the brake usually is bigger, heavier, faster, higher tonnage etc, but both more or less serve the same function. To make bend with a hydraulic press you create a die which are usually home made, there's not much to it.

in a production shop this would be done with a cnc punch or maybe laser then a press brake. I'd check out the cost of outsourcing those functions if you are doing volume. having seen those types of machines in action, it might be cheaper to have a production fab shop do the work and your core business is product development, distribution, marketing, etc. depends on volume i guess, but there's no manufacturing intellectual property in the above part, the value is in the sales/marketing side.