Small brass parts - Polishing questions

Hello Metal Guys,
I'm running a garage business selling like like a dozen parts a month
of a very specialized clamp for a musical instrument application. The
parts are on the order of 1.25" long, have no detail, but have both
rounded surfaces and flat areas. I get the raw parts from a cnc guy,
and then have a lot of shaping and finishing I do myself. Although
mechanical in nature, they need to look nice, so the dominant expense
is this finishing labor. I shape with a small belt sander and a 6"
abrasive rubber wheel. I use tripoli on a 6" hard felt wheel, and then
rouge with a 6" cloth wheel. Everything goes along, but I'm wondering
if I can't cut my shop time on two issues:
1. The 6" hard felt wheel clogs up quickly. I scrape it with a burred
chisel, but I need to keep putting a fresh burr on the chisel. I have
some brown tripoli, red tripoli, and lately I've been trying the white
diamond dust compound. That seems to clog the least, but it leaves
more work for the rouge wheel. I also have some kind of black cutting
compound which I haven't used in awhile, but I don't remember being
impressed. Is there some cut/color buffing bar I haven't tried that I
should?
2. After polishing, I spend a whole lot of time cleaning the parts by
hand. A lot of compound builds up in the threaded holes. I've decided
to invest in an ultrasonic cleaner. I have used them in the past and
wasn't terribly impressed. Perhaps I was using the wrong cleaning
medium What kind of liquid works best in the bath for removing tripoli
and rouge?
Thanks for any help!
Reply to
lostfrom68jay
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A picture of the components would help in giving advice. Ive followed your method and there a missing link there. After belt sanding and your rubber wheel, you neeed to go then to a compressedescotchbright wheel. Madeby 3M. comes in various grades 6in by 1 in a brown grey colour. not a hardone. This will eliminate your felt wheel part and theres no clogging. then you go to a white cotton mop with your whi compo. this will be the fastest way. hope this helps. For some of the things I make I go straight from the belt sander to the scotch wheel, then to the cotton mop.
Ted Dorset UK. silver smith and minter.
Reply to
Ted Frater
Ok. My site is
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I think we might be talking about the same thing on the wheel. I don't remember exactly what it is, but it quickly removes all the sanding scratches and still shapes aggressively. From there I can quickly bring a shine with the hard felt wheel with much less dust that a regular cotton buff. I then finish with the red rouge on a spiral cotton wheel, which I find makes the shine last much longer than when I stop with the white stuff.
I am working in a small space, so the dust issue is a motivator for the felt wheel. But, I remember when I used to use tripoli on regular wheels I was constantly cleaning them too. Maybe I'm just anal?
Reply to
lostfrom68jay
You need a vibrating tumbler. You throw the parts in the tumbler with some grit, run it over night, empty it and change to a finer grit and repeat. Do this in steps all the way through polish. Find someone who reloads his own ammo and he can show you the process and tell where to get the supplies
Reply to
Gerry
Yep -- definitely. You can probably do this in 3 steps, using plastic polishing media. I'd use a coarse cut-down plastic pyramid for the first step, go to a fine plastic media to leave a matte surface, then rouge on walnut for high polish. One place to get the media (and tumbler for that matter) is RioGrande. If you call them, you can talk to their mass-finishing tech specialist for specific media recommendations. I think if you send them a couple of parts, they'll even do a trial run for you. Other places for media include Gesswein and Otto Frei.
Regards,
Bob
Reply to
Bob
Nice looking bits.
I happened to notice you are using Phillips head screws and the screws on the instrumeet are blade type.
Would it be a seling point to use blade screws? or offer a choice?
Just a casual observation from out in the weeds......
Reply to
Mark Dunning
Nice work, and nice product.
Guess we are usinng the same wheel!!. You say confined space? in which to work, dry sanding and cutting IS a health /lung risk. youll need to use a proper cuff type micron dust filter respirator, or install proper vacumn dust extraction. Otherwise you will pay dearly with your health. Do this properly!!
Reply to
Ted Frater
I wouldn't use blade or Phillips - Torq for me. Less slipping.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Life; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member.
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Mark Dunn>> Hello Metal Guys,
Reply to
Martin H. Eastburn
There would be an aesthetic advantage to blade screws, but I can't find suitable ones. They need to be strong, with a large flat under- surface. I'm using a 18-8 truss head screw and lacquering it gold. I've thought of getting them brass-plated. Some customers use brass screws, which look better, but I discourage this because of strength issues.
Reply to
lostfrom68jay
I'm with you, but as I said, it's an aesthic issue. Luthiers and string players didn't go to mechanical engineering school!
Reply to
lostfrom68jay
Yes, I hear you. I only use a paper painter's mask. Since I do this only a day or two a month, I figure I won't kill myself, but I would like to reduce the dust.
That's an idea, but I'm not sure I want to polish the threads. Wrapping/plugging them before tumbling would likely cancel out the labor savings of tumbling, and I still have to do a lot of shaping before the parts could go into the tumbler!
Reply to
lostfrom68jay
Nice looking capos. I just have one comment on the web site. On your installation page you refer to the body of the capo as a "yolk" (as in egg), shouldn't that be "yoke"?
Reply to
DT
Look in woodworking catalogs for dust extraction gear. Use standard foil flex or knockdown metal dryer duct for the collection system, 3" or 4", and you can use standard air conditioning tee-Y's and register boxes behind the grinder to get the airflow going that way.
Do NOT use plastic pipe for dust collection unless it's designed for the use (semiconductive static dissipative agents built in) - air moving at high velocity creates static electricity, and some metal dusts are flammable or otherwise reactive, especially when mixed. (Aluminum dust plus steel dust = Thermite.)
Bad things happen inside the dust collector, or at the corners of the piping, and then the fire melts right through the plastic, or all the static built up in the pipes discharges inside the cloth collector bag...
What are the threads on the capo arms? If it's a standard thread, you can buy socket head set-screws and spin them into the bodies with a tee wrench in a few seconds each, then toss in the vibratory tumbler. For the arms, there are standard sizes of dip-molded vinyl sleeves that can slide on over the threads, to keep them from getting dulled in the tumbler. And they both should be reusable hundreds of times.
And nobody I know has an extension on their bass, and there are a few. Darn. Unless I should talk them into doing it...
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Reply to
Bruce L. Bergman

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