Need help polishing Stainless Steel

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- GrayMatter
  
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posted
19 years ago

Sun, Jan 30, 2005 5:18 PM

I have some Stainless Steel pieces (several feet in length) that currently have a brushed finish. I want to buff / polish these to a mirror finish. I have a new bench grinder, but I have no experiece with buffing wheels and compounds. Due to the amount of material, I would prefer to do as little by hand (sandpaper) as possible, but I ultimately want a nice end result. What products (stitched wheel, felt wheel, firmness of either, compounds, etc) do I need to accomplish this? I have tried some buffing, but many of the deeper original scratches remain.

Any details on procedures and products would be greatly appreciated.

Thanks

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- Ed
  
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posted
19 years ago

Sun, Jan 30, 2005 7:50 PM

result. What

GM...

The concept of polishing is quite simple - You must start with a large grit (say 250 grit silicon carbide paper best) and grind /polish the whole surface -the using a smaller size grit (say 400 grit) remover ALL prevoius scatches made by the 250 grit using the 400 grit - continue to

600 grit, 800 grit (ALLWAYS cleaning before the next grit used with acetone or alcohol) then use sucessivly smaller grit say diamond particles in oil suspension 15=B5m, 6=B5n, 1=B5m finshing with colloidal silicon or aluminum oxide at 0.05=B5m. The use of paper or wheels is not of great importance (really only for efficency) - only uniformity of grit size and cleaing between grits is important for the polishing method.

This process of using a finer grit to remove ALL scatches from previous polishing is a lot of work. It can be shorten by electropolishing by commercial metal finishers - search Google for "metal finishing" for people who know how to get this done. DIY (Do It Yourself) is alway an opion - by time is money.

ED

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- alvinj
  
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posted
19 years ago

Mon, Jan 31, 2005 2:17 AM

Starting grit size depends on the original finish.

And, jumping one grit size too much, can actually take you longer.

Sanding at an angle like 90 degrees is the usual method to be sure you got all the old grit's scratches, before going to the next grit size.

When you get to the finest grits... that takes a learned skill to get right... all I know is-> I don't have it! :/

If you want to "try;)" it yourself anyway, start here...

rec.crafts.metalworking :)

This particular project sounds like it's too big of a piece to get inside your bench-grinder's guard. ...but once you get the "polishing bug;)" you might forget, and "quickly try your hand" at something small? :/

But more realistic, you will want something small shined-up somewhere along this process and this is what's going to happen...

It'll get caught in the polishing wheel and...

-without the guard or shelf- the little part will get thrown hard against the floor. :) Put down a soft floor mat?

-with the dangged guard around it- it'll get the crap beat out of it while inside the guard then, thrown across the room, if you aren't in the way. :)

Alvin in AZ (hobby knifemaker)