Satin finish problems with wire brush

I’m trying to use one of those crimped wire brushes for the Foredom
to make a satin finish on aluminum. The problem I’m having, though,
is getting it to be uniform. No matter how hard I try, I can’t seem
to manage to get it even over the whole surface. Does anyone have
suggestions on how to get it to even out?

Paul Anderson

Hi Paul,

Unfortunately, the short answer is ‘use a larger brush’. Probably a
4-5" diameter wheel spun on a buffer, rather than a teeny one on a
flex shaft. Either that, or use a hand brush loaded up with dish soap
under dripping water. If you have some coarse pumice powder, mix some
of that with a bit of dish soap, and some water (to make a slurry)
and scrub that around with a toothbrush. That’ll leave a nice satin
finish.

What exactly are you trying to finish? (the processes are different
for big things and small things.)

So, three questions:

(A) what’s the object?
(B) What’s the desired finish?
© What tool are you trying to use?
(C1) What exact process are you using to try to get there?
(C2) What other similar (or likely) tools do you have available?

1 Like

Paul,

If I understand your problem correctly, the pressure and distance
from your accessory to your work can have a huge effect.

Can you send me a picture of the accessory you are using?

Until then try this. Take a few scraps of aluminum.

  1. Measure the distance how far into the brush are you pushing the
    metal of the wire brush, meaning from the bristle end towards the
    center.

  2. are you using a flexshaft or are you using a fixed higher speed
    polisher? If it is a flexshaft, then test the finishes at a few
    different speeds and see the difference.

  3. if it is a fixed speed polisher and the brush is large, find the
    sample that works best for you and try to stay at that distance.

Sometimes holding your work and moving back and forth from the end
to the center with a fixed speed will give you varied and uneven
finishes. It’s imperative that you hold it as steady as you can. The
amount of friction and bite into your metal will vary greatly if you
can’t secure your work at a fixed location.

Lastly, keep a light touch on the piece. Sometimes we want to force
the metal into the bristle wheel. Let the wheel do the work, relax
your hand and I bet you will achieve a more even finish.

Otto Frei has them. They are not cheap, use them slowly and yes,
wear eye protection as the little pins can fly off like shrapnel.
However the finish is yummy. I made a little texture sample plate on
brass so I could tell which one to use. If you are using the lathe
mounted ones, you need to be right at the edge and be very, very
gentle.

Miniature Texturing Wheel .15mm White-Max rpm 6000-Eye Protection
Must Be Worn

Part No: 111.489.5 You get the same texturing abilities as the lathe
mounted wheels in these easy-to-use miniature texturing wheels
mounted on 3/32" mandrels for use in flexshaft handpieces. Just like
the larger wheels, goggles and full face protection must be worn when
using this product. Available in 7 color-code…

Your Price: $34.95

I actually use those scary wire wheels which give me a great pebbled
finish on my work with a flex shaft.

Good luck!

Karen Christians
Cleverwerx

You don’t say how bit the piece of aluminum is but the best way for
me to get an even satin or polished surface is to use the buffing
machine. Basicaly, the wire wheel is too small to get an even finish.

marilyn

You can get a beautiful satin finish with a manicure sponge from the
beauty supply. Use the fine finish.

Hi Paul,

I use the brush technique often to give a satin finish, may I tell
you my method which was taught to me when I was an apprentice some
45 years ago. In my workshop I have what we call a scratch brush
unit, this is a polishing motor mounted on a moulded plastic unit
which allows water to drip onto the polishing mops, the motor spindle
is mounted so that the point of the spindle faces you when working.
This means that you face the circle of the mop and also that you do
not get covered in water splashes.

I use 3 to 6 inch diameter brash brushes on this unit and here is my
method of creating an even satin finish. I will try to describe my
working method, which is easier to show than explain. First I will
bright polish the surface that will be satin finished, using my
standard polishing motor and calico mops.

when the surface is polished, I degrease the item before attempting
the satin finish. On my scratch brush mashine I have a steady trickle
of soapy water dripping onto the rotating 5 inch diameter brass mop. I
hold the item to be polished in my left hand and a length of quarter
inch round steel rod in my right hand. I will hold the steel rod onto
the upper edge of the spinning brass brush, breaking the flow of the
brush, while holding the item to be satin finished below the area
that I am holding the steel rod.

In simple terms this method creates a system that makes the ends of
the brass bristles strike the polished surface, thus giving a perfect
satin finish. I am sure that you could use a similar method on your
foredom, but only on small areas. I have used my method to satin
finish an eight inch diameter bowl. If you need more details please
email mail direct.

May I wish all, peace and good health for the new year.

James Miller FIPG

If you are moving the wheel parallel to the direction of the satin
finish you will find it imposible to get a uniform texture. Move the
wheel sideways instead. So that the movement is parallel to the tool
shaft and perpendicular to the desired satin pattern. As you
continue this side to side motion slowly advance into the untouched
metal. In this way you avoid those long swiggly scratch marks. You
will need to develop a very regular rythm.

In my last post I mentioned a scratch brush unit and it occured to
me that these may not be available throughout the world and my
description may not be good, so I have found a photo of one from one
of our UK suppliers which I include as an attachment.

One of my oldest trade friends was a gold and silver plater, by
trade, and he used to construct his own scratch brush units, using a
square timber frame and a plastic bowl with a simple tap unit
mounted on the top of the frame to hold the water. He also had a
speed controller for the polishing motor as he used slow motor
speeds when polishing his colour gilding. His brass mops all had
wooden centres holding the brass bristles and he kept them all in
buckets of water, a process which keeps the bristles fixed tightly
within the wooden centres, I use the same process. The scratch brush
is also the perfect machine for polishing high relief chasing and
carving, as the polishing method of the brass bristles actually
burnish the surface and do not remove any surface metal, as which
happens when normal polishing with a calico mop and polishing
compounds. Another interesting fact from my old friend was that he
used beer and soap as his lubricant for scratch brushing antique
gilding. He was well regarded within the trade here in the UK and
often restored museum pieces of silver ware, items worth millions.

Peace and good health to all
James Miller FIPG in the UK.

Hi all,

Just to second James’ comment, we had a similar, albeit homebuilt
machine at the university studio where I did my undergrad work.
(Syracuse. It’s probably still there.)

Worked beautifully, and is high on my list of ‘toys to build when I
have space’. One trick that ours had was that the spindle was run on
a double-ended shaft set in pillow blocks, and run by a cone pulley.
(So you could change the speeds, although we always left it in ‘dead
slow’.)

One side was the brass brush with water drip, and the other side had
a great huge bucket of pumice, and a set of bristle brushes. (and a
big metal splash shield to keep the mess mostly contained.) Both
sides had an adjustable water feed. The pumice wheels were absolutely
outstanding for working holloware.

Regards,
Brian Meek.

James,

I find the 3M radial wheels in a flex shaft produce a gorgeous satin
finish. I’m sure the radial wheels are much easier to use than a wire
brush. Can you get the 3M radial wheels in the UK?

Mary A

James - thanks for the picture of the scratch brush unit. Very
interesting.

I use a simpler method - I have a very old but excellent brass brush
(mounted in a wooden handle). The bristle part is about 4 inches by 1
1/2 inches, very fine brass bristles. Haven’t seen one with such fine
(meaning slim) bristles like this in a very long time I dip it in
dish soap and then in powdered pumice and brass brush my piece (not
stones but the silver/copper (I don’t work in gold). It gives a
beautiful satin finish… Easy to do, cheap materials to have
providing you can find such a great brass brush. I’ve had mine for
nearly 15 years and it’s still looks almost as good as new and it’s
seen a lot of use.

Mary A,

Yes we have the 3M radial wheels in the UK, but I am an old timer
who likes to use my tried and trusted methods. My scratch brush unit
has served me well for the past thirty years so why change it.

May I mention another method that I use for quick frosted finishing
on small items. I have a pendant drill similar to a Foredom and I
install a 30mm diameter brass brush radial wheel in the hand piece.
Then I hold a needle file in the same hand with the file teeth
against the hand piece and the round handle of the needle file passes
through the bristles of the brass brush. When rotating the brass
brush this method allows you to gently frost a polished surface as
the needle file handle breaks the rotation of the brass brush and
allows the bristle ends to frost the surface in the same way I
explained on my previous posts.

James Miller FIPG

I use a simpler method - I have a very old but excellent brass
brush (mounted in a wooden handle). The bristle part is about 4
inches by 1 1/2 inches, very fine brass bristles. Haven't seen one
with such fine (meaning slim) bristles like this in a very long
time 

They are called Plater’s brushes. I get mine from Allcraft, but I
imagine most suppliers could get them, if they don’t already carry
them. Sometimes one can find them with plastic handles. They last
better because the wood on the usual ones eventually seems to
crack… I use them mainly for burnishing the oxide finish after
applying liver of sulphur. Turns the sometimes spotty dull black to
a burnished sheen with a wonderful blue/black “gunmetal” sort of
color. I find that holds up better than the unbrushed liver of
sulphur finish, and I like the color better too.

Peter Rowe

Hi Paul,

For a nice Satin finish I usually use the magnetic tumbler filled
with needle type shot. It works great for me. I would say that if you
are using the flex shaft and a texturing too, to work in a grid
pattern if you can, moving slowly from one side all the way across,
then stepping it down to the next line and working backwards to the
start (across, down, across, down) and keep repeating that process
until you have gone all over the piece. (This is the way we polish
glass too) Then once you have covered the entire piece, go back over
the areas you seem to see that are not quite finished.

And just a thought about Aluminum in the shop: be very careful where
you work on it and about cleaning up ALL of the mess. If any filings
are on your bench near any silver soldering equipment, the aluminum
gets into the sterling or even into fine silver and really pits it
badly. At university we were not even allowed to work aluminum in the
jewelry studio at all because of the mess it could make of
semi-precious and precious metals.

Good luck and hope that helps,
Teresa