Motorized Scratch Brushing

Have you ever thought about setting up a motorized scratch brush? If so, take a look at mine:

Used primarily for cleaning and burnishing metal. The lower translucent tubing supplies water. Should the piece require the help of a detergent, the upper tubing is connected a valve attached to a HDPE gallon jug containing 100% plant-based dish soap. It’s a gravity-fed system. A crimped nickel wire goblet brush is attached to the extension arm which was made at a machine shop. The translucent tubing to the left of the image is attached to 1/2" copper tubing via a saddle valve. I attached shrink tubing to the shaft to eliminate scratching in deep objects. The motor runs at 1750 rpm with a shaft pulley of 1" which belt-drives a 3" pulley = 583 rpm.

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Very Cool…… what type of finish do you end up with….?

Andy “The Tool Guy” Kroungold
Director Tool Sales & Stuller Bench
Stuller Inc.
P 1-800-877-7777 ext 4191 or 4194

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When you indicated that you use it for cleaning, I’m guessing you mean heavy cleaning, such as cleaning up a dirty old tool or like when the family silver has finally been found after being hidden in the swamp 150 years ago?

Hi Betty,
G Hermans setup is not for heavy cleaning of rusty etc tools .
He will im sure explain thats its a holloware as in silversmiths work process.
I thought Id come in here as I do a great deal of old tool restoration up to big as in 3 ton drop hammers and power presses and imput the following.
!. you can take the work to the tool or,
". The tool to the work.
If you really want to derust BIG stuff you use say a 6in by 2in wide wire brush wheel on a 2hp motor. you SHARPEN!! the wire ends by running them against a 6 or 8 in dia grinding wheel side on… This makes the wire ends really sharp. After some use you take off the wheel and reverse it to use the otherside of the sharp wires.
However you must wear thick leather gloves, i hope you dont ever get your fingers up against such a wire wheel. Its not pleasant!! you skin and etc comes off very fast and takes a long time to heal.
also you need a face mask or proper vacumn system to prevent rust, paint oxide etc lung illness.
Also of course an eye shield.
Despite all that its a real pleasure to find something good then restore it to its former glory and use.
Ted.

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Andy, it’s a rather soft look, though, it depends on the wire material and it’s age. It was especially popular during the Arts & Crafts period through today. Here’s an image of a Jensen Wave Bowl I refinished using a crimped nickel wire (.003”) goblet brush:

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Scratch brushing also burnishes also hardens the surface and closes microscopic porosity. The finish is sometimes applied to copper depleted objects to brighten the white (fine silver) surface that appears after pickling.

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Thanks Ted.

I’ve never worked on a tool larger than one of my ancestor’s anvils, which was difficult to clean with the wire wheel, even without the long-lost horn.

Thanks for explaining how to sharpen the wire wheel.

Jeffrey- Well NOW you show us this!
I still have some lovely old brass brushes like yours from back in my liturgical and repair silversmithing days. I usually just ended up making a big wet soapy mess out of myself and the collector hood.
XO Jo

As (I think) the sole watchmaker on this forum, I’m somewhat surprised that you went to all that trouble to get this type of finish. This same type of finish, which watchmakers call a non reflective brush finish is done by a wide variety of methods in watch making. In production, one of the favorite methods is sand blasting using glass beads. You can get a very wide variation in the softness of your finish. But for single one off work, there are a wide variety of synthetic brushes for buffing machines made by 3M (and some Swiss copy cats) for doing the same type of finish that use a plastic type material for the actual brush, rather than metal. It gives a much softer looking finish that a metal brush. These brushes come in a wide variety of sizes. For watches, I use a 6 cm diameter mounted on my buffing machine. With a variable speed buff, you can get an even wider variety of finishes, and then depending on your lubricant, you can vary the finish even more. Three lubricants I’ve used to good effect are sewing machine oil, water and dish washing detergent and straight dish washing detergent. Special tape is also available from watch parts supply houses for masking areas that you don’t want to buff over.

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I use my scratch brush unit for polishing heavy detail items, the benefit of this system is that it really burnishes the surface without removing metal, so you can polish gilding or silver plating without removing the plating. My main use is for finishing my carved crests that have chased detail, I also use my scratch brush for adding a matt finish, I hold a stick across the spinning brass mop just above the items surface which makes the brass bristles hit the polished surface with the bristle tips thus adding a matt texture. The photos show my scratch brush unit and one of my silver crests on a matt finish background.

James Miller FIPG

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That’s really exceptional polishing work. With the methods I use it would be impossible to do it as well as you have; the methods I use also have the disadvantage of taking off plating. When I have to matte plating I do it by hand using very fine grades of non oiled steel wool. Of course this is only good for small areas. But I don’t have to do large areas in my types of applications.But this is absolutely top flight work you are doing, and far superior to anything we are called upon to do in the watch making world.

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The gravity fed soap setup is epic;) I’m going to rig one up for my cleanup area. Thanks for sharing.

And the heraldry discussion…awesome, I think I’ll design a coat of arms for myself :wink: