Sandblasting question

I have that HF unit Stan is talking about. Although not the best in the west, it works OK. One improvement is to replace the pickup tube. Bend a piece of 1/2" thin wall tubeing in a U. Drill a 1/4" hole across the tube at the bottom of the U. Keep one end of the tube above the sand (I extended it thru the mesh grate and wired it to the grate to hold it in place) and run a piece of flexible hose from the other end of the tube to the gun pickup port. It works much better than the pickup they give you. Glass bead media wouldn't touch hardened SS so I use a mix of glass beads and AlOx that I buy from Grainger. Can't remember the Part No. but if you look as my past thread replys, the part no. is in one of them. I think the finish is great for hunting knives, skinners, B & T knives, etc.
 
The biggest expense in sand blasting is the compressor. It doesn't matter what else you have, if you can't even propel the sand for as long as you need in order to perform a uniform finish on a knife. A small compressor from the big box home improvement stores won't cut it. Sure, it might spray for a few seconds but quickly you've exhausted your tank and the compressor is trying to pump up the air but you are expending it faster than it can be created. If you have one, post up the SCFM specs and we can determine if it will work even if you have to spray until it turns on, and then wait until it gets back up to pressure.

I have the middle size Harbor Freight cabinet. There is one smaller which could work for you IF you won't be doing any large bowies. I updated it by using silicone to completely seal the entire thing because despite the claims, they do a horrible job. I added lights as well as new gloves and purchased a better gun from Eastwood. This is one of the few guns out there which can be dialed down to use a compressor that only supplies 9 SCFM instead of most which want almost 20.

Also, you'll need some way to clear the dust inside the cabinet, regardless of size. Spray for more than 10 seconds and you won't be able to see your hands inside. I've adapted a shop vac but it uses a water trap as well to keep it going as long as I can. The water trap works extremely well.

IF you have a compressor that can supply the eastwood gun (the harbor freight gun really needs around 15 to work somewhat decent), and purchase the smaller harbor freight cabinet, I'd guess you could have a setup to do smaller knives for around $250.

Thats the small cabinet, new blast gun, silicone to seal the interior, lights to see, blasting media and parts to make a water trap (without it, you'll kill any shop vac within a few blastings, the fine dust is MURDER). Plus some hours in fabrication to get it ready to use.
 
Just to reinforce the above....
It isn't the gun that matters most, it is the compressor you have. If your compressor won't supply enough CFM at 80-100PSI, don't get a blast gun. The money is in the compressor. One that will do reasonable abrasive blasting will cost around $800. 220VAC is needed. If it runs off 120VAC, you can pretty much bet it won't supply enough air. Also, don't get an oiless compressor.

Lots of people look at the rating on their compressor and say, well, my compressor says it supplies 4.7CFM at 90PSI, so it should work sort of OK. Sadly, it is not like a grinder where a bit smaller motor will work "sort of OK". If oit isn't as big or bigger in capacity, it will not work.
 
I'll second all the recommendations for the compressor. If you are underpowered, blasting will be a dreadfully painful experience. I bought a barrel blaster and love it. It costs a little more than the HF cabinet but is much higher quality. The gun is good and the cabinet has a port for a small shop vac. I bought one from Home Depot on sale for $39 and it works great.
 
One trick that works is to connect two smaller compressors together to the line with a "Y" fitting. That allows twice the CFM.
 
I bought the Barrel Blaster and it works great. Not too expensive and very well made. But you need a good compressor and a good water filter, that's the key.
 
I used a small cabinet blaster and a 6 gal. pancake compressor for occasional bead blasting of pistol slides for nickel plating.
It worked very well. You can't use it like a water hose, but if you are doing small objects it worked well. Just use short bursts.
I have since "upgraded" to a smaller, all-plastic cabinet using the same compressor.
 
On the compressor... he CAN use a small pancake compressor, he will just have to wait on it to catch up and will be running it hard. I did the for a bit when I didn't feel like hooking up my big compressor in my old shop. IF I just had 1-2 small blades to blast. If you are doing any kind of volume or blasting off other paint or something yeah you will need a big compressor.

When I was using a 4 cfm pancake compressor as I stated above, I was doing it to supply my huge 4'x2' cabinet that uses 29 cfm or so at 100 psi. It can be done, but you may wear your compressor out prematurely lol. Now that I'm in the new shop I am running the same cabinet permenantly off of a 7.5hp 80 gal Eaton that keeps up very nicely.
 
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