Making A Square Hole In Stainless Steel

The best way to do it is to sub it out to a guy with a waterjet cutter. Have him cut the sheets to size and cut the square holes. You then don't have to handle the full sheets and the holes, as well as the cut sheets will be within a couple of thou. We sub that type of cutting out. That is the reason we are getting rid of the punch presses. For .062 stainless 304 steel the cutting rate is about 120 inches a minute.

John

Look into the Roper Whitney hand operated lever punch press. It'll do the job and they don't cost that much. Talk to my friend Mark Fullerton at Precision Graphic Systems in San Diego He has one of these and a ton of die sets

I just got off the phone with a guy in Fair Haven New Jersey who is auctioning punch and die sets on eBay. And he told me that I'd still get distortion, and that there is no way I can accomplish what I want with one of the portable hand punch presses. But now that I come to think of it, he may not of known that I had intended to drill a 1/4" diameter hole first and then square it with the punch.

That's good to know.

So I guess going small(or cheap) is out of the question, huh?

Thanks.

Darren Harris Staten Island, New York

Does he have a website?

Thanks.

Darren Harris Staten Island, New York.

Thanks.

It seems that some here are implying that a portable hand punch/press wouldn't work for me. :-)

I'd be thinking about saving up for that, but I don't drive and I have very little room. :-(

If they made wobble bits for Rotabroaches I'd be set, since I recently won one on eBay.

Someone here posted this link a while back for square hole drills. I don't know if these people are still about in the UK I think. Maybe this is what you are refering to about Hougen and Watts brothers.

snipped-for-privacy@mail.c>Grant Erw>

Its not a hand punch,

I could probably get someone to deliver it.

The Whitney Jensen press is a arm crank press with a throat of about 24 inches. It really isn't portable in that the thing weighs about 250 lbs. It sits on a stand which elevates it to a good working height.

The footprint of this press is about 1.5 feet by 3.5 feet and stands about 4 feet high with the crank handle removed. The crank handle inserts into a slott on the side of the press.

The formula for the tonnage you need to punch the part is : (thickness of the metal, in inches) x (total length of the cut of the punch in inches) x (the shear modulus of the metal you are punching)

stainless steel shear will run between 90,000 and 100,000 depending on the alloy.

.062 thickness x (.25 x 4 sides) x 100,000 = 6200 lbs. or about 3.1 tons.

IF you want a picture of it send me an email.

This is the exact same press as listed on the roper whitney site. I guess they have upped the tonnage to 8 tons.

John

I submit that this is a really bad idea. Unless you make up a punch that has a

Properly set up, a punch makes very minimal distortion. If there were some, you could always set the piece between blocks and tap on the top block with a hammer.

It seems some people are responding to this posting with the impression that you may have to also put square 1/4" holes in stainless up to 1" thick. I hadn't seen this, but if so, punching is out of the question for material that thick and it would take a very large machine to do such even if you could find a punch that wouldn't shatter. On the other hand, broaching doesn't make sense for sheet metal. A small square hole in sheet metal? NO BRAINER - punch it and be done.

GWE

I decided on stainless because of it's stiffness and resistance to corrosion.(But if someone can recommend a better material that is not expensive I'd appreciated it). :-)

As for guiding, through practice all I'd have to do is determine exactly where two sides of of the punched hole will be so I can mark accordingly so I know exactly where to put the edges, and I should have no problem with positioning for accuracy.

You lost me on that one.

Of course punching is out of the question for stainless that is 1" thick. That is why I was attempting to get more info on the wobble bit that makes a square hole. But as for this particular project involving

P.S: That punch on eBay we were discussing has 5 tons of punching power, but I am still considering John's offer. The problem is that his is not portable. :-(

Thanks.

Darren Harris Staten Island, New York.

Yes he does it's gopgs.com