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greg lindsey
01-24-2013, 11:09 AM
Hi gang, I am looking for a small lever type punch press for punching holes in SS, most of what I use is 20ga material. I have looked at Di-Arco punches and they run about $900-$2500. I really only need to punch some mounting holes from time to time on tags and whatnot. Normally I have my steel vendor do it, but run into an occasion when a cutomer wants a one off tag or two and it's a pain getting my vendor to do these. Does anyone know of a small (inexpensive) press for doing this. What do you use? I've seen the one Marco sells but not sure if it would handle the 20ga stuff. I know this probably should go into a different forum, but was hoping some of the laser people have done this.

Thank for looking.

Richard Rumancik
01-24-2013, 11:37 AM
Stainless steel is difficult to punch and can be brutal on tooling. You need really tight die clearances or the stainless will try to extrude giving a nasty sharp ring on the back. Personally I'd be more inclined to use a dedicated drill press for this operation and invest in some high-quality aircraft drill bits. If you are doing multiples you could make a fixture to align the tags consistently. (A wooden base with an L- attached that can be clamped to the drill table.) You might need to use a couple drill bits (a pilot and a final) and/or a countersink tool on the back. But if I was only doing a few at a time I'd lean towards a drill rather than a punch. Sometimes you can get stepped aircraft bits that will make a pilot and then a final size. That's my opinion based on my attempts at working with stainless . . .

greg lindsey
01-24-2013, 11:49 AM
I had a feeling that was the answer I would get, I guess a drill press would be the most econominal way to go. Really just wanted a press cuase it was "cooler" LOL. Looks like a trip to HF is in order today.

Thanks Richard

Richard Rumancik
01-24-2013, 4:13 PM
A press might be right for some applications but setting it up could be a pain. Not the best for a couple parts here and there. I bought some good quality surplus bits some time ago and realize how much junk the hardware store variety can be. So I'd spend some money on some real drill bits instead.

Frank barry
01-24-2013, 4:57 PM
Hi yes I think a drill press is the way to go I think

Even though I am from Ireland I worked in a tooling company for many years and we made many drill for aircraft companies
There is no comparison between them and drills you buy in a store it’s like night and day they have a made from high quality steel and most have a special point an s point or a split point which will self center
You could try a carbide drill
Frank

walter hofmann
01-24-2013, 5:14 PM
Hi there
i use a handpunch heavy duty from harborfreight for holes not bigger as 3/16 works fine on 20gage and the punch is abut $ 80
greetings
walt

Mike Null
01-25-2013, 8:09 AM
I'd check Craig's list before HF.

Jim Coffee
01-25-2013, 11:24 AM
These individual punches (http://www.grainger.com/Grainger/knockout-hole-punches/electrical-tools/hand-tools/ecatalog/N-939Z1z0r4kw) are what come to mind when I read this thread.

Richard Rumancik
01-25-2013, 11:31 AM
Jim, the smallest knockout punch will be way larger than the mounting holes that Greg is trying to make.

Greg, I'm not saying that the holes can't be punched with a press-type machine or maybe even a hand operated punch. But my hand punch can't do stainless (it is not a heavy duty punch) and normal die clearances are too much for stainless. And I would really have to lean on it to punch through. So if you did decide to go to a punch, you might still need to get some appropriate dies to go with it (which will probably not come from HF.)

'Jacques Malan'
01-25-2013, 2:41 PM
Drilling would be the easiest, especially for just a few pieces.

As Frank said, invest in decent drill bits, we work with stainless sometimes and it is different from mild steel.

There is a formula (http://www.image2punch.com/Calculation-for-Punching-Force) for calculating the tonnage needed to press, you can look at that, the tooling is sometimes more expensive than the machine.

And just for a little gloat without pictures, I found a little 4 ton eccentric press at a scrap yard a few years ago, and paid for it about $50, and that included the die-set. I just had to clean it. It is now standing in the corner of the workshop punching 4mm holes in everything.

Uma Duffy
01-25-2013, 4:34 PM
Hi Greg,
Try Accu Cutter Company, out of Pennsylvania they have what you are looking for.

James Rambo
01-26-2013, 1:34 PM
would something like this work?
http://www.harborfreight.com/air-punch-flange-tool-1110.html
I have used one but punching hole in for auto body sheet metal work.
just an option to look into.

Rodne Gold
01-26-2013, 2:14 PM
Use a high speed steel/cobalt drill , not tungsten carbide (it chips) , you need a drill bit with a flattish tip and lots of back clearance , you need sloooow rotational speeds and a lot of lube (diatsol or dromus , even tapamatic) We find parallel engraving cutters with a big relief angles work better than bits , tho you may struggle to get one.
The problem with SS is that if it overheats it work hardens and will just break bits afterward. It really is important to have minimal flex in the press and the part needs to held down really firmly , use some sort of backing block the drill can penetrate after it breaks thru the 1mm stainless. If you ever see smoking when drilling or smoke where swarf hits the coolant , it's bad....you will really struggle to drill that piece

Randy Digby
01-28-2013, 3:39 PM
I have three of the style "A", each set for a different diameter punch. The puches are not hard to change out but I use all three sizes several times on a typical day.

http://www.mcmaster.com/#bench-mount-punches/=l8hq96

You can find more info on the mfg page here:

http://roperwhitney.com/punching/2-12.cfm

Brian "Rallyguy" Genrich
02-07-2013, 4:58 PM
Unipunch products make some pretty decent tooling for projects like this. You would still need a press of some sort, but you can get the tool holders very cost effectively on ebay, and then buy the punch and die for these..Tooling is very cost effective for holes. Your biggest expense would be the actual press iteslf.

We use ours on stainless, brass, and aluminum

Here are some videos (http://www.unipunch.com/VideoGallery.aspx) of their use in industry. All you need is one tool, that will fit multiple diameter punches and dies.



Brian

Mike Null
02-07-2013, 5:30 PM
Brian

Good to see you on the forum. You are welcome to list your company name and location in your signature.

In the meantime I'll post your site and tell members that you do first class work.

http://www.rallyeproductions.com/Custom%20Shapes.html

Brian "Rallyguy" Genrich
02-07-2013, 8:18 PM
Thanks Mike,

Good to see you as well. Finally jumped in on a 16"x24" Vision Router/Engraver, and figured this would be a good place to get some tips.

We're used to working with the old Wizzard XL technology, so it's nice to get into the modern era and have software solutions that are a bit more visual than the old iron.

Looking forward to learning, and helping in areas that I can....Punching metal being one of them.

The holders are around $50 bucks on e-bay and tooling is really dirt cheap if you can find a punch press and know how to set it up with deck.

I can take pics if anyone wants to see more....Our setup is much more basic than the video links I posted.

Brian

Stan Lightner
02-08-2013, 9:03 AM
I started out as a toolmaker & prototype machinist and am now working as a manufacturing engineer. What others have said about cobalt drill bits is correct, they need to be properly sharpened and use plenty of cutting fluid. Tap Magic or even old fashioned pipe threading oil are good choices.

Start your hole with a combination center drill & countersink. If you try to just start drilling with the twist drill it will wander and end up way off location.

As to punching, if you were making lots of holes that would be the best way to go. You would need a several ton punch press and accurately made dies something you will not get with a hand held punch or even a bench mounted general purpose punch.

For the drill press, get something of quality. HF drill presses are very poorly designed and manufactured. Your spindle speeds will be severely limited and the table will bend from the downward forces. Go on-line and find a good used Clausing or Powermatic industrial grade machine with a variable speed head instead of some inadequate machine.

You may want to consider having a local machine shop drill the holes. You would not need to invest in the tooling & equipment and could devote your time to engraving.