I require to use a press brake to get some work done. But there isn't one in my shop ... or a minimum of there had not been one in my shop. In this Instructable I will reveal you how I made my own press brake.
For those of you who do not understand, a press brake is a tool for bending metal by pushing 2 passes away together. They can be powered various ways, however without a doubt the most popular technique is some sort of hydraulic cylinder to use actual tons of force. Lucky for me my store has a hydraulic press. So all I need to do is make up some press passes away that fit into my press. And by another amazing coincidence I take place to have a great deal of really heavy steel that might really easily (less so in hindsight) be made into those passes away.
Step 1: The Plan
Anytime I develop something I do it in a little a slap-dash fashion. No matter how comprehensive my strategy I constantly find myself improving or altering things as I go. But the preliminary idea is typically quite close to the end product.
Often with jobs like this I will have a look around on the web and see if someone else has much better ideas than me. In this case there were a couple of concepts that I included into my strategy. The general strategy is to use the beefiest hunks of steel from the steel rack to make a base to hold the passes away, and a heavy beam to distribute the force of journalism cylinder over the width of the die. And for some factor I desire interchangeable dies so I can do radius bending in the future.
What it's made of:
1" x 6" x 30" Steel bar
1" x 2" x 26" Steel bar
1/2" x 6" x 26" Steel bar
1-1/4" x 1-1/4" x 26" Steel bar x 2
3/8" x 3" x 28" steel bar x 2
3/8" x 4" x 30" steel bar
3/4" x 12" cold rolled round stock x 2
3/4" x 6" schedule 40 black pipeline x 2
1/4" roll pins x 3
And an old spring that didn't belong to anything essential
Some things I utilized:
Vertical milling device
7" angle mill
4 1/2" angle mill
And sundry other hand tools
Action 2: Cut and Prep
To begin I cut the different pieces of stock to their prescribed lengths. Which in the start was the base, passes away, guides, and beam. Later on I would "choose" to add a couple of extra pieces.
Step 3: Machining Interchangable Parts
This is the most time consuming step. To make the dies I require to machine the stock to a shape appropriate to be press dies. I did things a little out of order but it made good sense at the time, or possibly not, I don't believe well in layers. Since I want interchangeable dies I require a way for the die and press beam to connect to one another without being long-term. Which means my preferred method, welding, runs out the image. Instead I opted for machining a slot the length of the die and cross drilling a few holes for roll pins. That way when I want to alter dies I simply drive the roll pins out and change them with the new die.
The factor this takes so long is since I have to remove a half inch by one inch by the 26 inches of the die. Which is a quarter of the volume of the entire piece of stock. Many great machinists will tell you to eliminate material using the fastest possible approach. Saw out the area of stock you need to eliminate then machine it to the preferred dimensions. Rather than investing all the time machining all that material. Sadly there is no way to achieve this rapidly. None of my tooling besides the milling machine has the capacity to remove the necessary product.
Step 4: Machining Upper Die
After the slot has actually been grated I require to shape the die like a die. To do this I cut a bevel on both sides of the die. Because I removed so much product from the die to make the slot in it I had to move a piece of 1/2 inch X 1 inch X 26 inch steel bar. This was so there would be something to resist the clamping pressure of my work clamps. Remember how I thought I might have done things out of order?
Likewise I am practically favorable that there is a better method to setup this machining process. But with my minimal tooling this is the best I might do. This is low accuracy machining here folks.
So back to bevels. I set the head of the mill to 40 Degrees, because for some factor 45 Degrees seemed too aggressive to me. 40 Degrees also manages me the option of flexing past 90 Degrees. Because 40 plus 40 is 80! I did not desire a sharp knife like edge on the die either. Because I want to flex metal not suffice. So I chose the approximate variety of 1/8 of an inch to separate each bevel throughout the working end of the die. In result producing a very tight radius pass away.
Step 5: Machining Lower Dies
The lower passes away are machined in exactly the same manor as the upper die. I even left the head of the milling maker at the exact same angle. One factor for this is it provides lets me have nearly completely mirrored angles to align with one another. But mostly it was since altering the angle of the milling head is a horrendous pain in the neck. I dislike to make any modification to take something out of square, since it is so much work to make it square again.
So just like the upper die I cut a bevel in the two pieces of stock that would become the lower passes away. The one oddity here is that the pieces of square stock I had laying around were not the very same steel alloy. One die half was softer and was simple to device. The other was more difficult and took twice as long to maker. In the future this might trigger some concerns, but spent for steel is paid for steel.
Action 6: Final Machining
Up to this point there is an upper die, two halves of a lower die, and other lumps of metal that need to become helpful parts. The 1/2 inch X 6 inch X 26 inch piece of steel bar requires to have holes drilled in it to match the three holes in the upper die. And The 1 inch X 6 inch X 31 inch piece of steel bar and the 3/8 inch X 4 inch X 30 inch steel bar need holes drilled in them to accept the 3/4 inch round stock.
Action 7: Welding the Press Beam
Now to mess up all this lovely machined metal by welding it together. Truthfully there was a course for me to make this a 100% machining task, however I do not have the persistence or the time for that. I was raised by a welder, so welding is typically the simplest way to get stuff done.
The main press beam is comprised of 4 parts plus the upper die. The 3/4 inch pipe requires to be welded to the 1/2 inch X 6 inch X 26 inch piece of steel bar. However because of a lack of insight it needs to be 28 inches long. Whoops! So in my slap-dash style 2 pieces of 3/8 inch X 3 inch X 28 inch steel bar will be added to journalism beam. I have actually been informing myself this will include strength and rigidness to the part. However truly it's simply a hastily applied band-aid.
Step 8: Welding the Base
The guide rods (3/4 inch round stock) require to be welded to the base plate (1 inch X 6 inch X 31 inch steel bar). These guide rods require to be square to the base plate to ensure appropriate and smooth operation. I didn't quite achieve this. The very first rod went great but the 2nd one was a little sour.
When welding I always attempt to think about how the thermal expansion/contraction will impact your work. In this case I had a little too much heat in one area for too long and the resultant "draw" pulled the rod to one side. The good news is in this case it is workable because of the short length of the parts. Otherwise I would have needed to eliminate the weld and tried again.
Step 9: Minor Adjustments
Part of handling the wonky guide rod is beveling the holes in the plate for the lower passes away. The sharp shoulders of the holes won't move easily down the guide rods easily. The very best method to deal with this would be to countersink the holes. But I don't have countersink bit big enough for a 3/4 inch hole. I do nevertheless know a way to add a bevel to a hole this large. Over the years I've discovered the most convenient method to bevel holes is to grab an action drill and lightly drill the shoulder down.
Step 10: Welding the Lower Die
Now that journalism beam and base are together the lower die can be welded. There needs to be some space between the die halves so I re-purposed some 3/8 inch essential stock to serve as spacers. When I get whatever where I desire it the welding can start. After a few strategically placed tack welds I am able to remove the clamps and spacers and weld things in earnest.
Action 11: Clean-up and Finishing Touches
Once I have whatever welded to my complete satisfaction it's time to make it as pretty as possible. Any sharp edge or corner is rounded over with a grinder. Splatter and weld smoke gets struck by a wire brush. And the unsightly uneven welds are smoothed with the mill.
Action 12: Does It Work?
After making it pretty it's time to see if it will get the job done it's produced. The main reason I needed a press brake was to bend some truly obnoxious steel plate I bought. This plate is a solidified abrasive resistant alloy. Every other effort I made to bend it showed useless. But this homemade tool flexes it simply fine.
For More Info
Step 13: Get Back to Work! (video).