Sanding steel

[RandyM]

When it comes to polishing I use varying degrees of grit with this. It is the fastest thing I have found for doing flat pieces. Now, you do have to make sure you secure the part well, I use soft jaws in a vice for this, with or without a rubber interface.

http://www.globalindustrial.com/p/p...MI2r2rrcG-2AIVQp7ACh3-MwokEAQYBSABEgL5U_D_BwE

 

[magicniner]

I use a 3" DA Sander for small parts prior to polishing, it allows me very good control at the edges so I can have them nice and sharp or rounded as required. Parts can prevented from moving around using double sided tape on a backing plate.

 

[Cobra]

You have to start with a corse grit and work your way up. Hard to say how corse as that can vary depending on the material and the depth or the profile you want to remove. Maybe try 80 or 120 then 220 then 320 and so on till you get to where you want to be. Also, buffing wheels with emery compound then white compound for the final polish. Another possibility is using a convolute wheel or belt. But the plater is correct, any imperfection in the part will show in the finish.

The thing to watch for is that at each step ALL of the scratches from the previous grit are removed. One of the easiest techniques is to sand at a different angle to you can see the earlier scratches. If you don't remove all, you will have to go back and remove.

 

[woodchucker]

If you have a die grinder or air grinder (same) get the rolloc sanding pad, and get some sanding pads, and scotbrite pads in different grits and go at it. slow but better than you think. The other way might be to get a tumbler and let the tumbler at it ..

 

[woodchucker]

I'm surprised your plater did not mention electropolishing before doing the nickel plating. When electropolishing is done correctly with the correct bath and anode, it will leave a near mirror finish with very little prep work.

Never heard of electro polishing. Expensive? Does it get into every nook and cranny...

 

[4GSR]

Never heard of electro polishing. Expensive? Does it get into every nook and cranny...

Yep! I haven't priced it in several years. AT the time it was a lot less than sanding and polishing.

 

[Maplehead]

UPDATE
So I purchased those 3M/Scotch Brite Roloc 2” conditioning disks. They come in course, medium, very fine and super fine. They worked well and they don’t wear fast. However, the super fine is not a mirror finish. It’s more like in the 300 to 400 grit range and of course with circular sanding marks. So I found out what knife makers were doing. I purchased a Harbor Freight 1” by 30” grinder/sander. I purchased a bunch of belts in 400, 600, 800, 1000, 1200, 1500 and 2000 grits. The pic here shows the results of sanding just this one side to the finish you see. I think I can get away with the quality of this finish for nickel plating. My problem is that I completely wore out every belt in the process. What is up with that? I have many parts to prep and I cannot use up a belt grit per piece. This is getting pathetic how difficult this is to get these damn pieces to a mirror finish. Anybody have any better ideas? I am not going to hand sand for hours on end per piece. I need to use a machine. However, I am not going to go through 7plus belts per piece either. There’s got to be a better way.

 

[4GSR]

Get the finish down using 400 grit, call it good. Nickel plate, come back and do your polishing with rouge and buffing wheel. Don't use sanding belts. Still think electropolishing is your best bet if your talking about a lot of these to do. There's plenty of information on the net about electropolishing, too.