Polishing picks in a tumbler?

[Drifty Flintlock]

By tumbler in this case, I mean like a rock tumbler.

Many moons ago, I saw a Youtube video of somebody, maybe Schuyler Towne, using a tumblr to polish laser cut picks. I can no long find the video or I would just check that, but that tells me it's possible.

Now, I realize machine polish will never be as good as hand polish. That's fine. But after recently seeing some picks fresh out of a water jet, it would save me an awful lot of time and effort to be able to throw them in a tumbler for deburring and basic polish, especially on some of the hard to reach edges. I have access to a small tumbler. What I'm not too sure about is what media to use. The owner of the tumbler, who is allowing me to use it, suggested maybe glass beads or pecan shells.

Any other ideas?

[kwoswalt99-]

What about rock tumbling polish?

[Jacob Morgan]

One would have to use a hard media to deburr metal, or have a large tumbler where the different parts being tumbled would fall on each other a lot so they could deburr themselves. I worked at a stamping plant a long time ago that deburred with no media, the stampings (they weighed a few ounces each) themselves beat the crap out of each other and wore the sharp edges down. That tumbler was about the size of a portable cement mixer so there was some physics involved as the parts fell down onto each other.

Ground up walnut shells and that sort of thing would be more for cleaning, reloaders use it to clean cartridge brass between reloadings. Here is a link to a seller of industrial media http://www.kramerindustriesonline.com/tumbling-media.htm , it has some descriptions of what sort of media is good for what.

I'm not sure what rock tumbling polish has in it, may be worth a shot if you have some available. Unless it is coarse it might polish more than deburr. It might be easier to find tumbling media in the form of sand blasting media: medium or coarse aluminum oxide would be interesting to try, as would Black Beauty slag. If you know anyone who does sand blasting, a quart of either of those items might do the trick. Might work best to combine different sizes of media to polish and deburr at the same time?

I think Eddie the Wire's book on making picks said something about tumbling, I'll see if I can find it.

[MBI]

There is media made specifically for what you're talking about.
It's been many years since I had to find some, but even back then with the less-capable search engines of the day I think it took me less than a half hour to fully research it, find out what I needed and find a competitively priced vendor that had the right stuff.

If I remember right I ended up with ceramic media. It came in many varying shapes, sizes, hardnesses and abrasiveness, depending on the size, shape and material that you're tumbling. Just make sure to read a bit and get the right stuff. Some will just put a fine polish on your steel parts without rounding off the edges much, some media will disintegrate without doing much to your steel at all. It's not rocket science, but you do need to select carefully to get the appropriate material.

Now that I go back and read my post I'm realizing I'm saying basically the same thing as jacob. But, I already wrote it out, so here you go.

[femurat]

Some years ago I invented "the sanding blob" that basically was a sand suspension to drive your pick through and get it sanded. The thread should still be here. The pictures may be gone but I'll be able to upload them again on Monday.

Cheers

[femurat]

I've just re-uploaded the pictures, here it is viewtopic.php?p=349890#p349890

Cheers

[Jacob Morgan]

Looked up Eddie's book last night. He suggested using ceramic or sandblasting media in a tumbler with oil. He was very emphatic about the need for oil (he used motor oil). His book gave a sketch on making a tumbler from a paint can and an old motor.

He also said that he was not sure about using a vibratory finisher (like hand loaders use). Well, tried it last night with some blasting media and it was OK at deburring soft steel, but not too useful at anything else. That was after throwing in a handful of drywall screws to toughen things up some more. I did not want to add oil because normally the unit is used for something else and I don't want oil residue in it. The bottom line is vibratory cleaners are probably not the way to go.

[MBI]

The bottom line is vibratory cleaners are probably not the way to go.

I've used rotary tumblers and vibratory tumblers and the main difference I noted is that the vibratory ones are MUCH faster, at least with soft metals.

Now admittedly, I haven't used a rotary tumbler for deburring harder materials like steel, I've only used vibratory units for that, so I can't directly compare how the two would be on steel. I'd have assumed the vibratory would still be faster, but I really don't now. The vibratory units will work on steel though, you just need to have the right media.

In addition to the right hardness and abrasiveness, the media comes in a plethora of different shapes and sizes. You need to select a media which is both the correct size to fit into the nooks and crannies of the stuff you're polishing, but also the right shape. Some pellets are spherical, tapered discs, cylinders, and yet others can be some rather odd and complex shapes to ensure good polishing coverage across the entire surface of your material. Sometimes the shape of media that works best is pretty bizarre and nothing like what you'd have guessed you should use.

If anyone has seen that movie Inception you might be familiar with the tiny steel spinning top that a character carries in his pocket. I could swear that the top he's carrying is actually a piece of vibratory polishing material, which just happens to work as a top but wasn't designed to be such. It looks absolutely identical to some of the vibratory polishing media that I've used.

[Jacob Morgan]

The vibratory unit was a mid-size unit from Lymann. It was not an industrial sized unit. Usually it cleans up brass with crushed walnut shells and does OK with that.

If non-industrial vibratory units could be made to work with the right media I'd be very interested in the details. After the less than impressive experiment last night I was worried someone might go buy a vibratory unit from a sporting goods store and be disappointed.

[MBI]

The vibratory unit was a mid-size unit from Lymann. It was not an industrial sized unit. Usually it cleans up brass with crushed walnut shells and does OK with that.

If non-industrial vibratory units could be made to work with the right media I'd be very interested in the details. After the less than impressive experiment last night I was worried someone might go buy a vibratory unit from a sporting goods store and be disappointed.

Yeah, that'd definitely be a bummer to buy an expensive piece of gear like that only to have it not able to do what you needed.

It's been a while and there's a chance I'm remembering wrong, but I think the vibratory polishers we were using were the largest ones Dillon sells.

Not too long ago I got a less expensive one from harbor freight to try out but I haven't unboxed it to do anything with it yet.

[Drifty Flintlock]

Thanks for the responses.

Using what I had available, I tried the Harbor Freight rotary tumbler with some glass beads. It was... okay-ish, but not great. decent side polish, but limited deburring and edge cleaning.

The more I think about it, it's more the last one that interests me. I can deburr with 2 minutes and 220 grit sandpaper. What I'm finding to be the hard part is getting into some of the finer curves on the picks, say on a long rake. What would be more useful is a way of smoothing those. I'm currently researching available media and we'll see what happens.

[Jacob Morgan]

If you need to get into corners and such you could try some India stones. They are like sharpening stones except they come in various profiles: round, triangular, square, etc., and in different grits. Use them with a little oil. An industrial supply house like MSC would have them. A gunsmith supply house like Brownells would have them too.

[Drifty Flintlock]

I think that would definitely help, and I'll look into getting some. Still going to see if I can get a basic level of edge cleaning out of a tumbler though.

[MBI]

What I'm finding to be the hard part is getting into some of the finer curves on the picks, say on a long rake. What would be more useful is a way of smoothing those. I'm currently researching available media and we'll see what happens.

Do what carpenters do when sanding intricate shapes. Wrap the sandpaper around an appropriate diameter dowel to sand inner curves. For other shapes, do the same but with a small block of wood shaped to hold the sandpaper in the right shape for whatever you're sanding, and it gives it a firm backing so you don't get uneven spots when sanding, like can happen when you just use your fingers.

[kwoswalt99-]

If you need to get into corners and such you could try some India stones. They are like sharpening stones except they come in various profiles: round, triangular, square, etc., and in different grits. Use them with a little oil. An industrial supply house like MSC would have them. A gunsmith supply house like Brownells would have them too.

You're thinking of slip stones, India stone refers to the type of stone, not the shape.

Drifty, I assume you're making a small production run.