Welding Tips and Tricks

Hey folks,

I wanted to gather some information about surface prep and finishing on stainless. I need to disclaim that I haven't started my the good bits of my project, but I do plan on doing some trial and error, but I figured it would be cool to also try out some suggestions from other members.

1. I am TIG welding up some simple stainless cubes to use a a base for some art pieces, I have all the material cut and prepped using dedicated SS cutting wheels and flap disks. I would like there to be some color left in the joints for show sake, but I was curious on if folks generally do finishing work before they weld so they get an as welded finish in the color and the surface finish on the rest of the piece is already done, or if they prep, weld, and refinish afterward.

2. This brings me to my second question: By hand or power-tools for Scotch-Brite. I have been hand finishing some steel projects Scotch-Brite pads, and was curious if that is generally the better method vs using an angle grinder with a Scotch-Brite pad. Hand finishing worked fine for my project, but I don't have any non-contaminated pads so I haven't tried on my SS yet.

3. Which power-tool leaves the best finish. Belt sander, bench grinder, or angle grinder with Scotch-Brite belt/wheel/pads etc. I have a bench grinder and of course a few angle grinders, and was looking at benchmark abrasives surface conditioning pads (3m Scotch-Brite knock offs more or less)

4. Is it worth going through 3 grits of Scotch-Brite, or just going medium only. I suppose this depends on the desired finish, but if were talking about a clean, relatively scratch free finish what do people tend to like.

I'm mainly asking all of this so when I go down to my LWS tomorrow I can grab a few abrasives to give it a go as a starting point and experiment from there.

Thanks!

Link to angle grinder surface prep pads from benchmark: https://benchmarkabrasives.com/collecti ... sc-25-pack

You might also consider using a felt or a cloth wheel on a bench grinder. You can treat it with polishing paste of different grits. Works good on small parts.

Poland308 wrote:You might also consider using a felt or a cloth wheel on a bench grinder. You can treat it with polishing paste of different grits. Works good on small parts.

Ya I have one that I used on steel and the piece came out nice. I'd need to grab another for SS. I think for those type of wheels to be the most effective all of the scratches have to be removed or else they shine through. The buffing wheels will shine up the part, but leave the scratches there as they're of course not very aggressive. I also found it to be a little messier than a regular abrasive wheel. The felt kinda flies everywhere and the rouge(compound) is very dusty when applying it.

You can get scotchbrite wheels that will go on there.

Flat stock stainless has a millscale on it that can be a bear to remove without multiple steps. All depends upon where you start, and what finish you want at the end.

I have belt sanders, a drum sander, orbitals, and angle grinders. You can polish by hand if the piece isn’t too big and you’re a masochist, but I prefer my air-driven grinders and drum sander for control. Walter makes grade discs, drums and belts and provides guidance on which steps to use to achieve a desired finish from a known starting grade. (They literally have an app for their abrasives with these steps and products).

If you end up removing the color, you can always whip a TIG torch back over for a quick, gently wash (use pulse if you have it) and get color back.

I picked up a 3m 2 inch roloc attachment for any 1/4 collet attachment for $22 and a box of 25 medium 3m 2in disks for about $24 . In total plus tax about $51 bucks. More than I wanted to spend but its likely $30 vs $50 at the end of the day and might as well not chance it on 20-25k rpms and buy 3m stuff.

If the medium disks alone aren't what I am looking for I'll try some of the other grits, such as very fine (blue) and super fine (grey

I also downloaded that Walter app. Pretty neat little tool to have on the phone. It will get you in the ballpark of what you might want to use, whether you go with Walter products or not. Thanks for the tips.