Blasting media

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Nov 30, 2005
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I am going to setup to do my own bead blasting (free standing from Harbor Freight). I will be blasting ATS-34 at 60C. What bead blasting media do I need to use? I am guessing glass bead media to avoid too rough of a finish, but do I want universal or like an 80 grit? Would aluminum oxide media be too coarse? Thanks for your help!
Jim
 
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Jan 16, 2006
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I have used glass beads (100 grit) in a vibratory tumbler with good results but using a blaster would be way more aggresive. You could just start out with aluminum or another softer media and work up through the harder medias unitl you find the best one. There are certainly alot of different media's to use these days.
 
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Thanks B Finnigan! Would a good shell casing tumbler with glass beads work and if so, how long does it generaly take to get a good finish?
Jim
 
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Jan 16, 2006
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On a knife that has allready been heat treated it has taken up to three days with the tumbler going 24hrs a day. But while one knife is getting bead tumbled I am working on something else (multi-tasking). It gives a unique finish but it is not the only way to finish a knife. Someday I would like to get a bead blast cabinet and starting playing with all the different media's that are out there. I am sure each one would have a unique characteristic to it.
 
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Mar 27, 2004
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I use the Glass beads from HF and have had great results. I too have the HF Cabinet.

Shane
 

Les Voorhies

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Nov 30, 2003
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I used a bead blaster at work at 1st, it barely fogged the ats-34 and looked really good on the TI and micarta. I have been using aluminum oxide but it is much more coarse (a bit too coarse IMO) and im going to go back to glass. I think the glass in the blaster at work was too fine for the ATS.
 
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Thanks guys! I went out and bought a HF bead blast cabinet and went after some ATS-34 blades I had ready to buff. The 80 grit glass media just barely turned the blade a dull polished look, like alot of production bead blasted stuff, maybe a little shinier. I had 25# of the glass bead in the cabinet and so I added 25# of 70 grit aluminum oxide and was very pleased with the results. It is slightly coarser than the smooth glass blasted finish, but I ilke it. I think the LEO folks I'm making for will like it too, they don't want any shiny. They will be the ultimate test, when I show them a finished knife.
Thanks again for the wealth of knowledge here.
Jim
 
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Apr 22, 2004
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Have you tried blasting with al ox and then with beads? That's my next project, though beads are very hard to find here.

I've had a very interesting finish show up on blades initially hand rubbed to 400 grit and then blasted with 220 grit al ox...very dark, rich colour.

Remember that grit will leave pits that create drag and provide points for corrosion, and beads leave smooth dimples.
 
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Nov 30, 2005
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Gawker, here is a sample of the mixed media bead blast I done on a small knife. Hard to tell in pictures, but may help.

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God Bless!
Jim
 
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