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J Tiers
08-10-2011, 10:15 PM
Are they supposed to do something?

I was advised to use the walnut hulls for cleaning/polishing.

So I tumbled some case hardware (steel)to clean up for re-plating, and after several hours nothing is happening, except some rusting because it seems the hulls are a bit moist and need dried out.

I may have to juice the hulls up with some 400 grit, or maybe some pumice, tripoli, or rottenstone, if I expect to get any cleaning action.

Suggestions?

Dr Stan
08-10-2011, 10:21 PM
Walnut hulls are great for aluminum and other soft materials. You may want to switch to sand or garnet for steel.

PTSideshow
08-10-2011, 10:26 PM
They are used in a vibrating tumbler not a rotary tumbler(extremely slow days rather than hours) They are also for light grime and dirt and rust. that is why a lot of people use them for cleaning brass shell casings. They generally are used dry. Any time you use water in a tumbler you will have to keep an eye out for rust unless the items and material are under water all the time they are tumbling
good source for information on the correct media (http://www.candmtopline.com/media_compounds.html)
Best place for information for pre plating media clean up is Eastwoods site and the forum.

J Tiers
08-10-2011, 10:48 PM
Hmmm.

The plan was to get the hardware cleaned up, then polished reasonably, so the platers wouldn't feel the need to do much (if any) touchup polishing.

Sounds like I need to go get a pint of sand and try that first, with a followup of hulls, or hulls and abrasive.

The folks I was talking to were acting like other stuff might cut too fast/too much. And the FIL gets clean casings for fast draw in a fairly short time. But he has some sort of liquid he pours in, slightly dampens the hulls. He gave me the bag of hulls (he had a big container), so maybe there was some of that mystery casing cleaner in already.

J Weber
08-11-2011, 12:01 AM
I shoot and reload a lot of black powder cartridges.They do get filthy.I use a vibrating tumbler with walnut media.It will work OK plain but takes a lot longer.I use a couple tablespoons of paint thinner [mineral spirits] into the mix to speed things up.It I have some really ugly ones I add tablespoon or two of rubbing compound also.My tumbler holds about a gallon of media with a couple hundred cases.Typical run time is 4-8 hours.I have done rusty nails a couple times.I let them run overnight.A rotating type tumbler is slower and takes a lot longer

gary350
08-11-2011, 09:03 AM
Rice works MUCH BETTER than Walnut hulls.

How did walnuts hulls became the thing to use when that are so worthless??????????

J Tiers
08-11-2011, 09:10 AM
Rice works MUCH BETTER than Walnut hulls.

How did walnuts hulls became the thing to use when that are so worthless??????????

Mebbe because you can't eat them?

Sand worked OK for the short trial I did. I had to use it in water, since the sand was damp when I got it out of the tub in the shed. Unless it was in water the tumbler wouldn't tumble (too much torque needed)

I'm drying it out to see if that will work better.

The tumbler is an old beacon engineering unit with solid rubber cylinders around 6 or 7" internal diameter.

garagemark
08-11-2011, 10:00 AM
I've never heard of using walnut shells plain. I use jeweler's rouge for my brass. They come out with a light coating of rouge, but after rinsed with a bit of solvent they look mirror polished.

vpt
08-11-2011, 10:04 AM
I thought walnut shells (hulls?) were only a blast cabinet thing? Never heard of people using them in a tumbler. I've only used abrasive grit in the tumbler.

PTSideshow
08-11-2011, 10:31 AM
As with everything, you can use the walnut shell in a cabinet, or with the cheap siphon guns/bucket(dry). People tend to add and use other things, depending on what it is you are removing or trying to remove. I have heard of almost every combinations of oils/solvents/cleaners/liquid detergents soaps.
The jewelry supply stores sell a detergent that you add to the stainless steel shot when cleaning silver etc. pieces or castings.

They(walnut) works better in a cabinet as the pressure does remove curd and light paint rust.

Rice, beans, and corn nibs in addition to rice hulls, and corn cobs and wood furnace fuel pellets will all work to the a certain extant.

And yes dry they do take longer, not many care to wait now a days. Everything has to be right now :D

Wet rice and beans wouldn't work well!
After chemical cleaning, dipping,media blasting with all the assorted media (basically anything that can be used) a lot depends on what is available locally cheap. Vibratory tumbles are next, both wet and dry (the favorite for small amounts as they have low cost bench top units) Rotary units are slow and small units for some lapidary work.

I have seen home made drum turners on rollers that use scrap metal bits and pieces with all kind of media and fluids added in. To small cheap cement mixes used with gravel on steel to deburr and finish parts for art work.

Be warned rotary tumblers used for steel and with steel media or gravel are loud and noisy Most have had to have insulated boxes built over them in home shop settings. Rotary tumbling will also work harden the items being tumbled. The size of the item dictates the size of the media used smaller items small media.
HF has plastic/ceramic media,soda,steel shot, and other small quantities or at least my local store does.
http://i35.photobucket.com/albums/d200/ptsideshow/Tools/DSCF9390.jpg

http://i35.photobucket.com/albums/d200/ptsideshow/Tools/DSCF9154.jpg

There really is no right or wrong way, it is what works for you.
Finishing.com This is the site for all things finishing (http://www.finishing.com/Letters/index.html) It is run by a guy that has forgot more about the subject than most experts know. If you send in a letter/question be warned this is truly a world wide info net work and your response may come from those people!

Frank Ford
08-11-2011, 11:17 AM
I use walnut hulls with great results - not used "straight," but with a liquid polish that does the actual work. For a great high shine on brass, I like Flitz:

http://www.youtube.com/watch?v=_ZTi8xiKOrA

I haven't done high polish on steel except on a buffer, but I'm sure there are tumbler polishing media just for that.

Toolguy
08-11-2011, 11:31 AM
I use a small HF cement mixer. I coated the inside with a spray coating of rubber to cut down on noise. For polishing brass cases, I use walnut hulls with liquid car polish. Once the car polish is well mixed in with no brass, the mix is fairly dry. Then is the time to add the brass. It usually only takes 2 - 3 hours to get the brass looking like brand new.

kevindsingleton
08-11-2011, 05:23 PM
I use a small HF cement mixer. I coated the inside with a spray coating of rubber to cut down on noise. For polishing brass cases, I use walnut hulls with liquid car polish. Once the car polish is well mixed in with no brass, the mix is fairly dry. Then is the time to add the brass. It usually only takes 2 - 3 hours to get the brass looking like brand new.

+1 on the liquid car polish with walnut hulls. I use it for polishing brass, and anything else that just needs to shine. It won't cut through heavy dirt or scale, but it will polish soft metals. For steel, or stainless, you'll need something a little more abrasive; ceramic, perhaps?

J Tiers
08-11-2011, 11:36 PM
I put some abrasive in with the hulls, and it polishes better. 400 grit and rottenstone

Dry sand is now tumbling, we'll see what happens. I expect it will work pretty well. It's not graded, there are fines, as well as everything up to almost small gravel in it.

Moral of the story is "don't listen to advice unless it makes sense"......

Walnut hulls at 150 mph out of a siphon gun is a bit different than walnut hulls dropping onto a part, or the part hitting walnut hulls.