Polishing Stainless Steel

[DavidTav]

Does anyone know if it is possible to polish scratches out of stainless steel? One side of my pulpit has some unsightly scrapes, it is not bent or twisted, just scraped, looks like it has been rubbed against a harbour wall. I was wondering whether it might be possible to lightly file the affected area then polish with buffing wheel? What do others think. Should I just leave well alone?

 

[vyv_cox]

Perfectly possible. Use wet and dry papers, starting with something like 100 grit, then progress to finer papers, for example 180 - 320 - 500 - 600, then polish when you have a nice matte appearance with the 600. I would not have a go with a file unless the scratches are extremely deep.

 

[steve_cronin]

Yes it can be done and in a quite straightforward way.

First you need to abrade the scratches out with some sort of abraisive paper until you are convident that all the scratches have been removed. This will of course leave a rough surface and this is probably what is concerning you, believing that the previous mirror finish will never return.

Fear not!

Now we come to the special way that the professionals finish the job.

This is Phil Thomas of "SteelMarine" of Nidri, Levkas Isalnd Greece putting the finishing touches to our gantry which he built onto the existing taffrail and you just can't see a join anywhere!

What he does after the abrasive paper (no coarser than 400grit) is to take the edge off with a soap pad and then gradually works down in fineness of abrasive until he's using 1200. Then using a callico mop (as supplied by engineering shops and some DIY places) in an electric drill (cordless are too slow, angle grinders too fast - 2600rpm - ideal) and rubbing compound like Farecla and then finally, as you see him here he uses a soft cloth and jewellers' rouge.

This is what a Calico Mop looks like - you will need an arbour to grip it in the drill though.

If it doesn't come right, you havn't put enough effort into it.

This will though, restore the mirror finish and you'll probably then tackle the galley hob too!

Steve Cronin

 

[doug748]

Yes not a problem, except you might be surprised how deep some of the scratches are, and may not want to remove the amount of metal that would be required. Have a little go at first. I suspect you might settle for an improvement rather than a full, as new, refurbishment. "Draw file" the area with a fine file ie use the tool sideways pulling it towards and away from you; then use finer grades of emery, before you polish.

 

[john_morris_uk]

You are right - although I have seen professional polishers use a special soap as the last stage. I don't recall the jewellers rouge - but if that's what you've got, it will work anyway.

 

[Billjratt]

saw a guy polish stainless with a wooden dowel in his electric drill, might be difficult on the curve of a tube though.

 

[Clyde_Wanderer]

If using the calico mop, you will need a pigs tail to screw into it which will fit into your drill, and the soap used for s/s is Phenol, ( not sure if spelling is correct ).
I would suggest starting with the abrasive flap wheels to fit in your drill, start with 40# then 80#, and then use fine wet & dry, then finnish with the calico and Phenol soap.
I have just finnished a s/s nose peice for my boat inc a new bow roller with 9"long x 4" high side plates which are 8mm thick, its taken weeks to get it to where it is now, but still some polishing to do on it.
I did use some of the blue s/s sanding discs which are brilliant for s/s and come in a range of grits, these are for small grinders and require a rubber backing disc.

 

[DavidTav]

Thank you all for the very useful replies - I will have a go!

 

[rogerthebodger]

this thread is how I polish all the stainless I made for my new yacht

 

[steve_cronin]

A pig\'s tail...

..is OK in a static bench grinder with the work presented in a parallel mode but on a hand held drill being turned and twisted about a structure of jointed tubes such as a pulpit, the mop will distort and come off. Furthermore, you run the risk of damage to the work from the tip. A left-threaded arbour is much more suitable because it is a secure mounting.

Steve Cronin

 

[Serge68]

For final polishing of such parts, I recommend considering Electrolytic Plasma Polishing Machines for Stainless Steel (EPP), the process takes 5 minutes, improves the surface quality by 4 classes.