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Gunner Asch[_6_] Gunner Asch[_6_] is offline
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Default Do not buy a Harbor Freight "rock tumbler"

On Sat, 29 May 2010 17:35:18 -0700, "Michael Koblic"
wrote:


"Gunner Asch" wrote in message
.. .

[...]

I got my corncob from the pet store for $6/ 1.8 kg. Enough to fill the
bowl
and have a lot left over. I run some brass in it but it has limitations.
Right now I have a batch going in rouge-treated walnut shells. Somebody
mentioned adding Brasso - I wonder how much per batch.


Try a tablespoon full. It spreads rather well and is simply a media
compound that is carried by your media.


Thanks. What do you do when you finish? Do you re-use the same media?


But of course. Brasso wont hurt anything and it adds a bit of polishing
action to whatever you put in there. More for the softer stuff, less
for the harder stuff.

I tend to reuse walnut hulls for many years. Its not so much the sharp
corners..which after a while..are gone..but its a great carrier for
Brasso, etc. even when rounded off. Brasso is nothing more than a very
fine media in a liquid carrier.

As I said I tried a silica crystals cat litter on some steel parts. The
results were surprisingly good but if run dry, the silica dust is awful
and
if wet, clumping occurs (duh, it's cat litter!)

I want the ceramics for steel parts and also plastics for de-burring
brass -
I am not sure the nut shells will do that job well.


Yes..they do a pretty fair job, though for steel, it takes a while. Soft
non ferris stuff goes pretty quick


So far I am more impressed with the nut shells than with the corn cob. As
far as I can see the corn cob will polish clean brass but will not remove
stains. The treated nut shells removed most but not all the stains, did a
great job polishing the pieces (up to 3") but did little or no deburring
(minor scratches still apparent after about 8 hours).


Ayup. It has little or no ability to remove burrs in anything hard. Add
a bit more Brasso..another table spoon and it will likely remove the
last bit of stains..which generally are etched into the material..just a
heads up. Might not be deep..but walnut hulls have little ability to
actually remove much metal.

The next batch I shall put some steel in the nut shells. What compound do
you use for steel? There is a ton of proprietary compounds out there. I hear
some people just put in a bit of turtle wax. I run the silica with just
water and dish- washing liquid with the predictable result of good cleaning
but flash rusting. I wonder if dumping in a bit of Evaporust would work.


Are you trying to deburr, destain or what? Walnut hulls are really not
much good for anything as hard as steel, other than for putting a nice
almost matt finish on it. Ceramics are what you need for steel.

What are you trying to do with the steel? Let us know and Im sure you
will have a lot of suggestions..some even good.

VBG

Gunner

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