What is the best and safest way to make these? I will be cutting them with my cnc plasma cutter. Im just not sure how to bend them.

They can be either mild - annealed or cold worked steel.

I am not concerned about bending the steel without the use of heat for extra strength (cold working). So heating up the steel with a torch prior to bending it is an option.

Should I heat it up and bend it in a well fabricated die (made out of mild steel). I will be able to make any kind of shapes, dies, bases etc with ease using my plasma cutter (so making a fancy die may be a option).

Input? Thanks!

Well, the bends look simple. If your not making alot of them you could bend in a large sheetmetal brake. Or maybe in a hydrulic press. All depends...

These are brake parts for ?? If it's life saving then these should be forged parts.

Its for converting from drum brakes to disc brakes on light truck vehicles. A TON of these get made and are really common and not one that I have heard of have been forged???? hhhhmmmmm

Those were probably bent on a 35 to 50 ton press brake in a die. Doing it that way would be the easiest and most accurate. You would want to keep the bends equal and plate parallel.

I dont want to ask any more newbie questions without studying more about dies and stuff but im curious, can the dies be made out of mild steel or will that just ruin them as the material that is being bend is mild steel itself?

I dont want to ask any more newbie questions without studying more about dies and stuff but im curious, can the dies be made out of mild steel or will that just ruin them as the material that is being bend is mild steel itself?

If you are doing just a few parts with a simple bend and do not have any really critical dimensions you can use mild steel dies to bend mild steel successfully. The dies will gradually die (excuse the pun) by deforming at the points of machine pressure.

If you never ask a question how will you ever learn and there is no such thing as a stupid question, ask away.

A die is made from A-2 or O-2 steel. They both are a hardened steel that is still machineable. Once you have machined the steel into your desired shape/configuration it is the taken to a heat treater to be heat-treated to a hardness of about 62-65c. Once back from the treaters the die is then finished up and mounted to a die set. Building dies is best left to a die maker or you could do a lot of reading and end up with a lot of hair pulling and scrap steel.

If you look at your picture of the adapter plate you will see a spot before and after the bend where it looks like it has been over bent. These are deliberatly figured into the die to over bend the steel because metal has a memory, it will relax some after pressure has been released from the bending process.

As for heating it up for bending, DON'T do it. Heating it will weaken it, it must be cold worked.

so this type of die will work for that kind of thing.. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7548453424

and it said its for 16 gauge... so the tooling has to be bit different than that?

thanks for all those info very helpful so far.. those plate are 3/8 thick which is very common bracket in my industry...

You could make a simple die out of hot roled plate stacked together to make the offset with a couple of pin's to line up the two halves and the plate tap the holes afterword's I think the machinest guide or a pressbrake manufacture can calculate the tons needed your shop press should do it .

PS. Looking at the bolt's in the pic. try to find some with shank to go through the plate and the housing end maybe oem with a knirled shank the threads dont have much shear strength.

You could make a simple die out of hot roled plate stacked together to make the offset with a couple of pin's to line up the two halves and the plate tap the holes afterword's I think the machinest guide or a pressbrake manufacture can calculate the tons needed your shop press should do it .

Yes, I dug out one I had made a few months ago and was going to take photographs.

Energystuff: Do you want to see it?

Based on my experience doing all four bends in the same die may need something like 80 to 100 tons. I was doing a similar but smaller offset bend in 1-1/2 by 3/16 cold rolled bar and needed around 30 tons. The bottom line is that it would be possible to build something up to bend some samples if a big enough press is available. For large scale production you go to the experts and get a proper die made.

If those plates are 3/8" thick then Danosb is correct in saying you will need a 80 to 100 ton press to get the job done. From the picture I was assuming a plate thickness of 1/4" and just bending alone.

Danosb,

What is pictured in the ebay auction is a punch for 16 guage sheet. It would not work for anything heavier, unless you would want to jam it up or crash it. The thicker the material that you want to punch the greater the clearance between the punch and the die must be.

Yes, I dug out one I had made a few months ago and was going to take photographs.

Energystuff: Do you want to see it?

Based on my experience doing all four bends in the same die may need something like 80 to 100 tons. I was doing a similar but smaller offset bend in 1-1/2 by 3/16 cold rolled bar and needed around 30 tons. The bottom line is that it would be possible to build something up to bend some samples if a big enough press is available. For large scale production you go to the experts and get a proper die made.

I am energyforce's friend we would definately like to see what you made! definately!! thanks!!!!

I have loaded up some pictures. First one shows the die and a bent piece. The offset on the part depends on the starting length and the position of the stop on the left of the die. The way the top die comes down the slope and is forced against the stop along with the stock means the bends are consistent. With this two step approach it is not possible to do a very short offset but the same simple design can be made longer to do both bends of the offset. One nice thing about an offset like this is the spring back is equal on both bends so your ends are parallel even if the angle of the offset part is not quite accurate

If those plates are 3/8" thick then Danosb is correct in saying you will need a 80 to 100 ton press to get the job done. From the picture I was assuming a plate thickness of 1/4" and just bending alone.

Danosb,

What is pictured in the ebay auction is a punch for 16 guage sheet. It would not work for anything heavier, unless you would want to jam it up or crash it. The thicker the material that you want to punch the greater the clearance between the punch and the die must be.


More specifically, the thicker the material, the wider the Vee die should be to keep tonnage realistic. This type of die could work given the proper dimensions. After all, this is bending, not punching.

If the standard lower die used on 3/8" is 3". The tonnage per foot is about 25-30 tons. Since this actual bend is about 6" in length adding the two ears, I would estimate it below the 20 ton range IF it were bent to a 90 deg bend. Since it is only a 45......it should not take all of that. Of course you will need to multiply that load times 2 for the suggested die forming 2 bends x 6" at 45 degrees.

The worst part about this is trying to keep the bend radius small. Looking at the part I think I see some coining on the inside radius. If anything, it is evidence of some serious tonnage developed to make the bends tight. Whether that is a product of narrow dies is to be determined.

Taking into account the bend length, the material thickness and the actual distance between the 2 bend lines. We could alter the 2 Vee die widths below the standard 3". The tonnage will increase, but one must ask if it is realistic for the strength in the dies themselves. The physical size of the supporting material in the dies set can compensate for this to some degree. The surface hardness of the dies will need to handle this increase too. Be very cautious HT'ing bending dies to a point that removes ductility. If they don't bend when over stressed, they shatter. How fast can you get out of the way? If possible, flame or case harden. At minimum, keep through hardened dies heavy or below 55Rc.

Another point to make in the die set. It appears that there would be a conflict with the bolt flange. That portion of the dies may need clearance.

Regardless of what approach these bends are done with. There can be some alignment issues between the 2 ears on the same plane? In a production environment, repeatability could be achieved once a pattern was obvious. Not so easy with low quantity runs below 10 and crude tooling? It would compound the problems with separate dies or an attempt to get away with one die set and bend each individually. Not impossible, but not very productive to say the least.

You can use this tonnage calculator to get an estimate in what it will take to bend a given thickness of material over a given Vee Die width. Play with the Vee die width to get an idea of what happens as it gets narrow. Remember that this is for a 90 degree single bend. No....I don't think 2 x 45degree bends will equate to the same tonnage. ;)

Bend Load calculator (http://www.e-ci.com/products/tc.php)

Most commercial plate bending dies are made to handle around 40 tons per foot of bending length capacity. That is only 3.3 tons per inch. Please keep these tonnages issues in mind to avoid a potentially dangerous condition!

DC