Need to punch 1" holes in .025" SS sheet

Prefer punching to cutting and don't really have the time to make a punch and die set, although looks like it would be fun! Does anyone know where to get individual punch and die sets of this size at a reasonable cost?

Thanks!!

Glenn

If you need something fast, Greenlee makes some sheet metal punches aimed at the electrician trade. They do require a hole drilled to pass a threaded stud through, so you can crank the punch and die together with a wrench. I don't know how many holes you have to make, but this can be a fairly cumbersome method, and you need to be able to get to both sides of the material for each hole. The phrase "reasonable cost" has some pretty wide latitude for interpretation, as well. There are also companies like Di-Acro (if they are still in existence) who make mated punch and die sets for use in their manual punch presses.

Yes but an electrician's 1" is not the same as a machinest 1", so Greenlee would not be a good choice

Greenlee makes std punches in inches. Just make sure you get a 1" punch, not a punch for 1" conduit.

I don't think you'd get good results from a conduit entry punch. The clearance is too large for .025" material, and stainless is real sensitive to clearance.

It would be easier to point you in the right direction if you told what you plan to use to drive the punch and die. If you don't currently have some machine to mount the tooling in, then a unitized punch assembly from Unipunch or Unit Tool would be the cheapest and quickest option. This can be powered via a press brake or a shop press, or even a good sized arbor press. Either company likely stocks the punches and dies with the proper clearance for your material. When everything is considered, such as the punch, die, stripper, die spring, and the frame to carry it all and keep it aligned, the Unipunch type tooling offers a lot of value for the dollar.

Right now I'm looking at about 50 1" holes. I've got a three ton Arbor Press and a 100 ton hydraulic press. I was just looking at manual Roper Whitney bench presses which look like a solution as I also need about 100 7/16" holes, but had originally planned to cut them with a RotoBroach type tool. Punching them all would give the best results. I was going to call Roper Whitney on Monday and question them about capacity with stainless and die clearance. I also have a 20 ton pneumatic press I could make dies for, but there is a limit on how much time I can spend setting up, as I spent the last couple of days making rolling dies and dimpling dies for other operations on this little project. Making the basic punches and dies for the pneumatic press (3" steel accurately aligned C-frame design) would be relatively simple as I do internal/external grinding and honing, but the last go around with the heat treaters took over two weeks. Then I would need some sort of stripper arrangement and I'm not well versed in die design.

Thanks for the suggestion! I'll track down Unipunch and Unit Tool on Monday too.

Glenn

Uni-punch makes punches and punch frames [unit frames] you can probably find the frames cheap on ebay and then get the proper punch and die for it. These will go in any press including your arbor press. 3 tons may be enough if you have some shear on the punch but it would be close. The Irwid unibits do a very good job drilling thin sheet metal BTW, no grabbing. I just drilled a 1/4" hole thru the end of a stainless rule with one,nice clean round hole.

My dad used some greenlee punches in an arbor press by just mounting both halves so they stayed aligned as well as an arbor press does that, it worked fine. it was used in plastic, the company he did them for had worked out the idea on their own and dads alignment and machining was nicer than theirs was

Bill

metlmunchr,

Thanks for the leads!

Got Unipunch frame and a couple sets of punch dies on the way ;

Glenn

Good to hear that worked out for you Glenn. I think you'll be pleased with Unipunch products.

When I was in high school I worked at my dad's shop. We would cut up about 5000' of angle iron every 2 weeks and fab it into flanges for high pressure ductwork. We had a ganged set of unipunches in a press brake and both flanges of everything got punched on 4" centers. Me and one of my school buddies probably sawed and punched 30 miles of angle, and I never remember a punch giving any problem. I'm 56 now and we've still got that same gang of unipunches. Don't make duct flanges anymore, but every once in a while I'll have some job where I set up a few of them to punch multiple holes in parts. They still work as good as they did 40 years ago. Parts off of ours would interchange with your new ones. Not many things around that are solid enough to not need any changes in close to half a century.