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darryl
04-22-2006, 04:12 AM
Helped a friend clean up some stainless sheet material tonite. It had been sanded by someone and the result was quite uneven, so we had to re-sand it to even out the texture. Not a trivial task, and time-consuming as stainless doesn't cut down very quickly. The best result I could get was using Vim cleaner and purple scotch brite scouring pad, after sanding it with something akin to a belt sander with al oxide belt. Any tricks to getting a good finish on stainless?

torker
04-22-2006, 09:56 AM
Darryl, that's a good question. I ran into a job a couple of years ago that I turned down. Got a call from an industrial kitchen installer that came to town to install some new kitchen counter tops in the local hospital. Was all thin guage stainless tops.
The guy who usually did his joining got sick and couldn't make it.
I could have tigged it all up in place for him but the finishing buggered me.
I saw some of his joints and still have no idea how he made them so perfect on such thin stock. From the top side you could never tell there was a joint there. I don't know what he used but the grain in the stainless matched perfectly.
I tried some with a belt sander, with the finest grit belts I could get here but it looked like crap compared to his. I wasn't about to put a whole lot into a job that was only a few joints and would maybe never do another.
Still has me wondering how he did it though.
Russ

Millman
04-22-2006, 10:05 AM
Torker, sounds like he may have used Cratex rubberized abrasives. I've used them on mold and die polishing to blend in and give mirrorlike finishes. That would be nice if they had it in a belt sander type pad; may have that by now.

WJHartson
04-22-2006, 11:03 AM
The finish on most of the commercial sheet is the "as rolled" finish includes bright sheet. Whatever pattern is on the rolls is transfered to the sheet during the rolling process. Processed plate may have a post finish operation that is usually done on a large machine that uses a scotch rolls to produce the finish required. The rolls can be purchased from 3M. They will make whatever you want. Some of the rolls that I have seen for finishing aluminum were 24" in diameter and 60" long. I had some made to post finish work rolls at an aluminum rolling mill so we could get the finish we wanted on the workrolls. I think someone makes scotchbright belts for a best sander but I don't remember who.

Joe

moldmonkey
04-22-2006, 02:05 PM
Joe-

I have had decent results with a die grinder with a ScotchiBrite Roloc wheel and 3M Stainless Steel Cleaner as a "cutting oil". It's mainly a matter of how much time you are willing to put into to it.

gunsmith
04-22-2006, 08:01 PM
I have had to even out the finish on ss a few times myself. If you take your scotch bright pad and using an orbital sander with a sanding disc installed you can scour the suface quite rapidly to a uniform finish. The reason I leave a sanding pad on the sander is because it grips the scotch pad and you don't have to glue the scotch pad to the underpad. Any type of orbital sander will do including air type. Depending on the finish you want you can also just use a sanding disc on the sander and get good uniform results as well. I'm talking about a flat non reflective finish, not a polished surface.

torker
04-22-2006, 08:37 PM
The guy who was doing the counter tops was using a belt sander according to the guy who was looking for someone to glue this together.
He showed me a sample and it was as Joe said...the same finish as the roll. It all had to be linear....no swirls.
The Scotchbrite sanding belts sound like what he was using. You couldn't tell were the weld had been.

TECHSHOP
04-22-2006, 10:09 PM
There is an aerosol(sp?) product called "Shelashine"(I think I spelled it right), It is for industrial/commercial use that will put a shine on stainless (it will frost most plactics). The "scratch pattern" is important when rubbing (green pad) to make it all match. I don't have a source, it is "good" stuff, and it is not inexpensive. Oh, and it doesn't like heat. Once had one can fall into a shrinkwrap oven, the pop took out all the observation windows (safety glass was 3/8 inch thick, 50ft+ away) to the production floor.

JRouche
04-22-2006, 11:01 PM
Orbital sander also.

Use a nice one with variable speed, I like porter cable.

I also use a light oil, I use WD40, helps the cutting action.

If the sheet is scratched deeply I check it with a fairly course grit to see if that will remove the deepest scratch. If it does not I go to the next grit up until I get to a grit that removes the scratch. Then I have to do the entire sheet with that grit and subsequently finer grits until I get the desired finish.

When sanding stainless wear a mask, your lungs will die inhaling stainless steel. JRouche

darryl
04-23-2006, 04:39 AM
Thanks for all the good ideas. I'll be giving them a try. I couldn't find a scothbrite belt today, but we do have a random orbit sander, so that's the first thing I'll try. We also have a reciprocating sander, so that will be an interesting experiment as well. I really like the belt sander idea, so I'll keep looking to find a scothbrite belt for it.
There's a long list of things that aren't good for your lungs, and now I'll add sanding stainless to that list. Thanks for all the info.

Someone also mentioned silver silicone as a gap filler and to hide imperfections. Anyone heard of that? Probably just silver colored silicone, and nothing special, but I don't know.

Ries
04-23-2006, 11:13 AM
Most welding supply stores sell velcro backing pads for 4 1/2" grinders and scotchbrite pads that velcro to them, usually in 4 or 5 different grits.
Klingspor Abrasives will make up scotchbrite belts for you in several different grits, custom for any size beltsander you have.
On stainless I use both of these, and I also often use a DA sander- an air powered autobody disc sander, with PSA (sticky back) sandpaper in very fine grits used for autobody work.

But no way around it, its a lot of work, and usuallly several steps, to get stainless to look good.

darryl
04-23-2006, 10:30 PM
a slight OT, but hey it's my thread.
I picked up a scrap of that 1/4 thick stanless that I was on about a week or so ago. Looking at the factory edges, it looks like it would have been cast. Opposite side has obviously been sheared, also obvious are the plasma cut edges. Can all this be? Could this piece, and possibly the 4x8 sheet I was drooling over be cast? Can you shear cast sheet? If this is rolled sheet, maybe the edge that makes it look like cast is actually the result of another method of cutting that I'm not aware of.
I wrecked a jigsaw blade on it today by trying to go too fast. This stuff grinds with dull red sparks, and the moment I saw these sparks when I was attempting the jigsaw cut was when the blade went south.
Anything I've done with stainless has been 16 ga or thinner, for the most part. It's obvious to me that if I want to use this thicker material, I'll have to have a more suitable way to cut and shape it.
And to think I was contemplating jigsawing the 4x8 sheet in half just to get it home!