Press Brake Project

[carlito]

Ok, so you guys win - I am in the middle of building rather than buying a small press brake. I have a pile of 3/8" scrap and picked up a piece of 3/8" solid square stock at Lowes tonight. So, i`ll keep this thread updated on progress and bend quality, etc - but for now here are a few *very* rough photos.

Thanks to Darren M. for the motivation! I knew I could do it, but figured I was too busy, this took me about an hour so far.

This one is small - as its just an attempt. Its about 13 inches wide and I only need to bend a few small pieces of 18 ga for now. Obviously I could have built a box style brake, but in the end I intend to bend alot of 3/16 and 1/4" steel, so this is a good practice brake to plan for a larger version later. I would like to pick up a "mini" mill next to machine some of these parts rather than weld them together.

Oh, yeah go ahead and laugh at the last pic - where my lower "die" warped a full 1/4" on each end. I have made another and only tack welded the bars on. I have not welded in a while and forgot about warpage!


PICS:

 

[gorilla]

Remember that the top die on a press brake need's to be less than 90 degrees to allow for spring back when bending. The bottom die needs to be 8X the material thickness wide for proper bending.

 

[carlito]

Thanks for the info, I am unsure how to deal with the upper die at the moment, but i`ll find something. For the thin material i`m working on I can take care of the extra few degrees needed. I think a milling machine is going to be very important for this.

 

[carlito]

I am happy to report that it works! I didnt take any more progress pics as there isnt much to this project.

This configuration bends 18 ga metal exactly as I expected it to. Has a nice tight radius and will make excellent patch panels for my Jeep. This brake was just a test however, and I will be building a new one out of better material before I actually make any patch panels.

So some issues - First of all the elevation of the lower "die" which is 2 piece of 3/8" steel, needs to be much higher in order to make a full box. So i`ll make a new lower die using 2x2" steel and weld the two 3/8" rods onto that. Second, because of my scrap metal and torch cutting nothing was very straight, so the square stock that was welded on ended up being slightly warped. Not a big deal, i`ll use 1/2"x3" plate for the upper die next time with nice straight edges to work with. Third, I just wish it were wider - 24" is about the maximum space in my shop press. Last, an air over hydraulic jack is in my very near future.

Beyond that, i`m quite happy - it will make plain 90 degree bends all day long, just no channels at the moment.



PICS:

 

[carlito]

I decided I will probably get extra 2x2" steel and make two or three dies, one for thin material and at least one more for thicker stuff.

I am going to attempt to find a retired upper die from a large press, seems like it would make the most sense although I have not had any spring back issues with the 18 ga.

 

[akdiesel]

Very well done.
The test subject looks like it has nice clean 90 deg bends.

 

[carlito]

Very well done.
The test subject looks like it has nice clean 90 deg bends.

Thanks, I was surprised that the bend came out so close to 90 degrees. I was expecting issues with spring back & that very well may be the case with thicker material.

 

[Darren M.]

Awesome!!! Well done. How much cash do you think you have invested in that little ******? Less than Harbor Freight I'd bet ya.

 

[carlito]

Awesome!!! Well done. How much cash do you think you have invested in that little ******? Less than Harbor Freight I'd bet ya.

Thanks & yeah, about 77 cents for the pair of springs - clearance from Tractor Supply. And then a little oxy/acetylene to cut the plates & some welding wire. I also bought the 3/8" cold rolled round stock for the bottom "die". I do have alot of improvements to make - beginning with new stock & two sizes of lower dies for different material. I also need to really watch warpage as the upper die does not fit the lower die tightly after welding.