Say... I want to tumble my magnets...

[rhgwynn]

You know, for that really old worn out look....

What should I tumble them with??? ( I have an actual tumbler silly, I mean what to put IN the tumble with the magnets) Do I, just tumble a crapload of them together? Or, just a smaller amount (30-50) with a bunch of..... rocks? sand? I can figure out the rest, like how long, etc. But what with?

-Rob

[David King]

Typically they'll use a viboratory deburring medium like ceramic cones followed by filbert or walnut shells. Harbor Freight sells the stuff, i bet gun stores that sell reloader equipment sell it too.

[ReWind]

"Say... I want to tumble my magnets…"

Is that an innuendo?

You can get some abrasive sample packs with various different materials on eBay and online hobby shops for pretty reasonable prices. You might consider that, just so you can try a number of different abrasives and see what you like, plus have some selection around for the oddball solution you know you'll need for some weird project one day.

[Bruce Johnson]

Magnets, like Alnico, are very much like metallic rocks. They are hard and brittle. To make a rougher surface on them, you need to make little chips with something that's equally hard and has sharp edges. If you use a fine abrasive, it may actually polish them to an even sheen, the opposite of what you want.

I would first try ordinary gravel stones. They are approximately free, and are probably very close to what you want.

[SpareRibs]

Hello, .
Have you considered soaking them in acid or vinegar, that may pit them if they are sintered. Another option could be chips of hardened steel from a cut off saw. I don't know about magnets but tumbling rocks sometimes takes days on end.

[rhgwynn]

Lots of great responses guys. Thanks so much.

Basically, I want to do whatever it is that Fender did to them way back in the day.

-Rob

[SonnyW]

You know, for that really old worn out look....

What should I tumble them with??? ( I have an actual tumbler silly, I mean what to put IN the tumble with the magnets) Do I, just tumble a crapload of them together? Or, just a smaller amount (30-50) with a bunch of..... rocks? sand? I can figure out the rest, like how long, etc. But what with?

-Rob

Actually for some of my models I do tumble the magnets. I made a homemade tumbler and I use the ceramic triangle media, water, and a tiny squirt of soft scrub. My tumbler runs at low rpm's, I think it is maybe 75. I usually tumble them for about six hours or so. It does make them duller looking. I tried using dawn soap, but it makes too much foam. I put a little bit of a bevel on the top end first. The tumbling won't create much of a bevel, but it does round off the sharp edge on the bottom end barely perceptibly but enough to make them go in easier. I took a pic, but it is pretty hard to capture the visual effect on film (ok 1's and 0's). The ones on the left are tumbled, the ones on the right are as received.

[David King]

Sonny, Those look great to me.

The vibratory deburring goes faster but that do you really care how long it takes. The mags are just sitting on the shelf anyway.

[SonnyW]

Sonny, Those look great to me.

The vibratory deburring goes faster but that do you really care how long it takes. The mags are just sitting on the shelf anyway.

Thanks, You are right on not really caring how long it takes. I usually do 100 or so magnets at a time, less if I get tired of beveling them. I put in all the same lengths and when done then put them in stock for when I need them. I don't tumble all my magnets, just the ones for some models. I would have probably preferred to use a vibratory deburring machine if I had one, but I had many of the parts laying around to make the jury rigged tumbler I use. It is a surplus gearmotor from I think maybe a copier, mounted on a board with an angle bracket. To that I attached a drum made of a cone shaped scrap metal part I had, which just happened to fit a large plastic butter tub, and inside that I made a plastic insert from a coffee container that has the ribs inside to make the magnets tumble. I did buy the gearmotor cheap from a surplus catalog I got somehow in the daily junk mail. It runs off of a transformer that I had already, so I only had to spring for an electrical box and a switch, and make plates and brackets etc. I found the ceramic triangle media on ebay. It is a bit noisy when it is running though.

[rhgwynn]

What I have is actually used for developing film. I have the large canister that holds 2 - 4 developing reels; and the machine you set it on to turn it so you dont have to shake the thing the whole time. It even has slightly uneven wheels to rock it back and forth. I found it all pretty cheap in a consignment store for about 15$ At the time I was only thinking about polishing rocks and whatnot, but I'll probably just use it for this now; or both...

-Rob