Finishing stainless steel

Hi Everyone,

I was hoping to get some tips on finishing stainless steel to a
mirror finish. Ive been at it for some time with not so great
results.

Currently I have been sanding 320, 400, 600 then moving to the
buffing wheel where I have been using a 5" cotton spiral sown buff
from white diamond to stainless steel compound, then red rouge. I
have tried the green rouge and didn’t like the results. Any advice
would be greatly appreciated.

Tired and Greasy

Zam is my favorite

Jeff Ellis

Hi Tired and Greasy,

For 316L stainless on flat surfaces, I use the 3M fine deburring gray
wheel(from Rio) to remove minor surface scratches. Then I go straight
to a tight weave muslin buffing wheel with Zam (from Rio) compound
and voila, a beautiful polish.

Hope this helps,
Reba

Currently I have been sanding 320, 400, 600 then moving to the
buffing wheel where I have been using a 5" cotton spiral sown buff
from white diamond to stainless steel compound, then red rouge. I
have tried the green rouge and didn't like the results. 

Proper way to finish steel is with clover compounds. Available in any
industrial supplies.

Leonid Surpin

Currently I have been sanding 320, 400, 600 then moving to the
buffing wheel where I have been using a 5" cotton spiral sown buff
from white diamond to stainless steel compound, then red rouge. I
have tried the green rouge and didn't like the results. Any advice
would be greatly appreciated. 

What I use to achieve a flawless mirror finish on stainless is the
following, granted if your piece is small you might have to use
different tools.

Any sanding/grinding can stop at 400 grit. From here, use a gray
deburring wheel (3M makes a great product) to smooth out the surface.
Then straight to a white rouge, on a 6" yellow treated buff on a 3400
RPM motor. Also, dont be frugal with the rouge, and you will be
applying a bit more pressure when polishing stainless.

If you dont have a grey deburring wheel, you can use the Advantegde
line of silicone polishers from Rio. I use the white version
exclusively and dont have to go any finer.

Lastly, if you really want it to pop, finish with a black rouge on a
soft cotton buff, then hand finish with Mothers brand Mag and
Aluminium polish, any auto parts store will carry this. These last
two steps are really for taking out the super fine lines that
sometimes show up using the yellow buff, but in most cases arent
really necessary unless you have a large surface area.

Yep, thats whats been working for me for the past umteen years, not
too much to add other than using a bit more pressure on the piece.

P@

Hi Folks…

Cut a ring out from a tube of some nasty stainless… It stripped
the teeth off the high carbon hacksaw blde I first tried… And no, I
don’t have specs on what type…It was industrial scrap…

After working the bejesus on it…

I found a final polishing with Simichrome gave me what I wanted…

Gary W. Bourbonais
L’Hermite Aromatique
A.J.P. (GIA)

I was hoping to get some tips on finishing stainless steel to a
mirror finish. Ive been at it for some time with not so great
results. 

When my husband renovated one of my motorbikes as a birthday
surprise, he polished its stainless steel exhaust pipes to a fabulous
mirror shine. He used rouge to start with and then a product called
Belgom Alu. He used soft cotton polishing mops. Here is a link:

http://www.mandp.co.uk/productInfo.aspx?catRef=503965

I’ve seen it on ebay also. It’s a liquid unfortunately but it was
doable and it was the best stainless steel polish around at the
time.

Helen
UK

HI All

it reall does depend what equipment you using Start with 3m Trizact
A45 (320) Then 3m Trizact A16 (1000) Then sisal mop with green bar
compound -then stitched cotton mop with white bar compound -then
swans down loose leaf mop with rouge or the finest you can get.
Remember if you put a scratch in it you have to take it out else it
is going to be highlighted when you get to the mirror finish. So take
more time with the A45 AND A16 you will be rewarded in the end. also
do not polish all in the same direction. do the first lengthways
then the next step at right angles to the first.

it will highlight all the scratches and you can proceed with ease
until they are all out. then the same with compounds etc etc. Satin
finishes are better for stainless as it scratches easy then your
mirror finish is marred.?

Hi Christine,

Although not practical, I have used this method to get a mirror
finish on stainless steel (flat surfaces only) using a Logitech model
PM5 lapping/polishing machine.

I start with 15 micron calcined alumina mixed with water (1 part
alumina: 10 parts water) on a 15" serrated cast iron lapping plate
that rotates at 70 RPM with about 3kg pressure applied to the part.
This step will make the surface planar. It can either take a few
minutes for small flat surfaces, or several hours for large slightly
lumpy surfaces. The tool top speed is 70RPM, faster would certainly
speed up the process, but it would also sling the slurry off the
plate faster wasting the abrasive.

Next, I use 3 micron alumina on the same, but cleaned, cast iron
lapping plate. The speed is 70RPM with 3kg pressure until all of the
15 micron features (not really scratches) are removed. Then I back
off the speed and pressure to about 30RPM and 1kg pressure. Although
dark, the surface should start to mirror (undistorted reflections in
the surface). At this point I adjust the speed, pressure, and slurry
load until there are no visible scratches.

Once I have a scratch free surface, I switch to polishing plate that
has an adhesive backed cloth that I charge with 3 micron cerium oxide
slurry. I run this condition for one hour to remove the most of the
dark mirror look, and then add a colloidal silica drip(product SF1,
0.125 micron). The colloidal silica has a high pH that weakens the
metal bonds, and the abrasive particle wipes the metal away. It’s
chemical mechanical polishing (CMP) at its best, where the cerium
oxide helps keep the mechanical removal ahead of the chemical
removal. If I don’t use the cerium oxide, the colloidal silica etches
too fast, attacking the grain boundary, and leaving an orange peel
surface. I usually run the colloidal silica drip for 30 to 45
minutes. Any longer, and the polishing starts setting up a wave on an
otherwise very flat surface (1 micrometer over 100 mm convex works
best for me!).

As others have said, remove as many scratches as you can, because
they will show up in the polish.

I took some pictures of a 100mm ss disk I did several years ago. It
has a lot of new scratches that the camera doesn’t seem to pick up.
It makes my heart skip every time I take it out to look at it.

Email me off list if you want to see the pictures.

Jeff

Hi Everyone

Thanks for the great suggestions! I hope to try them all but for now
Im going with the yellow spiral sown buff instead of the cotton with
a lot more pressure and things are starting to look better. Next time
Im out I hope to get one of the grey 3M wheels to try. I did take a
look at using the silicone wheels but my surface area is much to big
and flat for that, but I will probably use them in the future for
smaller work.

Still Dirty, Still Tired but much happier