Cutting stainless steel discs

[Jeff Waegelin]

I'm working on a project for work, and we need to figure out how to cut some stainless steel into 1" circular discs. The biggest punch and die sets I can find can only cut stainless up to 0.01", but the steel I have is 24 and 26 gauge, which are about 0.018" and 0.024". Laser cutting is an option, but not preferred, as we can't do it on-site. What other methods could I use to cut this material into discs?

[Gdeaver]

Green Lee makes a manual and hydraulic punch. Electricians use it to punch holes in electric boxes. There are also manual punches. I use a 1 3/8" one to put holes in stainless steel sinks. Works fine on 18 Gage 302 and 304 stainless. 29-4c doesn't punch as well. There is always the hole saw.

I didn't read the post correctly. You want disks not holes. See if a local machine shop can punch them out for you.

[Greg Perkins]

waterjet

[dlavery]

Get a piece of 304 stainlesss 1" round bar ($12.50 per foot from places like Online Metals, or even less if you are buying in larger quantities from any of the standard metals suppliers). Cut off slices in the bandsaw (if you don't need high-precision widths), or chuck it up in a lathe and part off slices (if you need to precisely control the width of the slice). You should be able to knock them out pretty fast.

-dave

[Andy Baker]

Give a 1/2" dia steel ball to Chuck Norris and ask him to clap.

(or... do one of the above, if Chuck is not available)

AB

[petek]

Assuming you want the disks to be flat, unless you have access to a serious (like 10 ton or so) punch press, I'd go with Dave's or Andy's suggestions. Whitney's chart says you'd need 4+ tons to punch 1" dia. in 24 ga stainless.

[Jeff Waegelin]

Originally Posted by petek

Assuming you want the disks to be flat, unless you have access to a serious (like 10 ton or so) punch press, I'd go with Dave's or Andy's suggestions. Whitney's chart says you'd need 4+ tons to punch 1" dia. in 24 ga stainless.

I think have access to a pretty serious press here. Unfortunately, we don't have the right tooling to punch out such a piece. Any idea where I could find some?

[sanddrag]

My suggesstion is to go on www.cnczone.com and/or www.rfqwork.com and post your drawing and get some quotes. When I did for something I had, I got probably 4 quotes within a day. It is pretty competitive over there. You might suprise yourself with how cheap it comes out.

[Jeff Waegelin]

Originally Posted by sanddrag

My suggesstion is to go on www.cnczone.com and/or www.rfqwork.com and post your drawing and get some quotes. When I did for something I had, I got probably 4 quotes within a day. It is pretty competitive over there. You might suprise yourself with how cheap it comes out.

I'll keep that in mind for future reference. However, I already have the material, and I'm looking to make quite a few parts (this is a prototype for a production part), so it probably needs to be something that can be done onsite, if possible.

[Joe_Widen]

Last year my team used a bandsaw to cut 1" keyed stainless steel rod. We used a lathe to scribe each cut. Worked fine. You could try using a mill with a solid carbide bit, that should do the trick (I heard the lighten those KOP gears in minutes). They are relatively cheap if you have the piece to hook it up to the mill. If i had to get one, Id buy <Vibration-Free Rough/Finish Carbide End Mill 3/8" Mill Dia, 2-1/2" O'all Length W/ Square End> part number <8745A13> from McMaster. Its $42.38. It would be a good investment if you need to make alot of them.

[DonRotolo]

Consider making the tooling to punch out the disks, and use your big press. 10 tons should be plenty.

The problem with Greenlee punches is that they keep the hole nice and clean, but bend up the disks created in the process. You need the other direction.

To mount on the press ram, all you need is a 1 inch diameter bar. Ideally of something hardened. The bottom surface should be flat, and the edges sharp, as that's what will do the cutting.

the female die to mount on the table is also a hard piece of something, with a 1" hole in it - but the top surface is not flat. (Trying to punch the whole circumference in one shot takes too much force). Instead, it is angled like a V, the depth of the V being about 5-10x the material thickness - maybe 0.100" or so. Deeper cuts better, but deforms the disk more.

The punch coming down hits the upper edges of the die - for example, at 12 and 6 o'clock - to start, and as it moves down, the cutting edge eventually reaches the low point of the V, at 3 and 9 o'clock.

Look at these to get the idea, but remember, these have the center punch like a V (kinda) and the outer die flat - you want the opposite.

Good luck,
Don