Shopsmith Forums

I have been thinking of getting a blast cabinet, but have never even seen one. Do any of you guys know what else I would need to start blasting? I have a compressor.
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You need a pretty powerful compressor to run these with any good performance. I have a Craftsman compressor but it only gives me 8-9 cfm at 125 psi and that isn't anywhere near enough cfm to run a blast cabinet. I was looking into them as well recently and most of them require somewhere around 15 cfm minimum at 90 psi. There are some guns that have very small orifices that will run on lower cfm output but you will be there all day blasting with those I am guessing. If you find something worth while please share with the rest of us. I still would like to get one as I could use it all the time for various repair work but I can't afford to buy another compressor to run the darn thing.

Mark, I have 2 cabinets. What are your intentions with a sandblaster? The HF Cabinet is a syphon blaster but it can be converted rather easily to a pressure blaster. The H F cabinets have a real tendency to leak as they are delivered, if you get one I would recommend using a tube of silicon caulking on the joints before using. Depending upon what you want to do with a blaster, you may want a pistol grip valve, a deadman valve or a Richman foot peddle valve. Another couple of options you might want to consider is a light in the cabinet and a port to hook up a dust collector. If you don't have a good dust collector hooked to the cabinet, by all means use a respirator. Silicosis is a nasty side effect of breathing the dust from blasting.

Media is another variable based upon what you want to use it for. Common medias are Silicon Carbide and Aluminum Oxide. Common grit grades range from 50 to 250. Other options are out there (ie. Black Beauty or slag) but don't waste your money on those, one run through and their wasted.

Let me know more about what you are wanting to do with one and I can get more specific.
Here's a good reference chart for compressor size required for a specific nozzle diameter/pressure combination.

Tom,
That chart is awesome and actually says that my compressor will work if i get a gun nozzle with a small diameter orifice. But what I wonder is how efficient will a small orifice gun diameter be for blasting i.e. how long will it take to blast a small part like say the headstock casting on the shopsmith???

wannabewoodworker wrote:Tom,
That chart is awesome and actually says that my compressor will work if i get a gun nozzle with a small diameter orifice. But what I wonder is how efficient will a small orifice gun diameter be for blasting i.e. how long will it take to blast a small part like say the headstock casting on the shopsmith???

Mike, still too many variables to give a good answer... 50 to 100 grit will cut much more aggressively (faster) than a finer grit, but on soft substrates (ie aluminum, pot metal, brass, etc) will have a tendency to pit the substrate. Pressure pot blasters are much more efficient than syphon blasters and will do the same job with less CFM and PSI, but there's the additional cost of the pot.

My big setup is a clam-shell cabinet and a 90lb pressure pot with a Richmond foot peddle valve. It's powered by a 5hp Ingersoll Rand compressor with an 80gal tank. Right now I've got 50lbs of 150AO in my pressure pot. I run 90PSI into the pot and regulate the pressure at the nozzle to 20-40PSI depending on what I'm doing.

Hey Tom!
As I look into blasting, what are your thoughts on a simple pistol blaster (siphon)? In addition to cleaning up some Shopsmiths, I am thinking that it might come in handy for cleaning lawn furniture, wrought iron, and such.
Thanks, Mark

Can I just siphon out of a bag of playground sand??

mark-b wrote:Hey Tom!
As I look into blasting, what are your thoughts on a simple pistol blaster (siphon)? In addition to cleaning up some Shopsmiths, I am thinking that it might come in handy for cleaning lawn furniture, wrought iron, and such.
Thanks, Mark

Can I just siphon out of a bag of playground sand??

I do not think 'playground sand' makes good blasting abrasive!

tom_k/mo wrote:Mike, still too many variables to give a good answer... 50 to 100 grit will cut much more aggressively (faster) than a finer grit, but on soft substrates (ie aluminum, pot metal, brass, etc) will have a tendency to pit the substrate. Pressure pot blasters are much more efficient than syphon blasters and will do the same job with less CFM and PSI, but there's the additional cost of the pot.

My big setup is a clam-shell cabinet and a 90lb pressure pot with a Richmond foot peddle valve. It's powered by a 5hp Ingersoll Rand compressor with an 80gal tank. Right now I've got 50lbs of 150AO in my pressure pot. I run 90PSI into the pot and regulate the pressure at the nozzle to 20-40PSI depending on what I'm doing.

Thanks for the insight Tom. I have a very good client of mine Composition Materials and they are in the abrasive blasting media business. They actually mix and maunfacture blasting media right on sight at their facility here in CT.

One of the most popular media at the moment is Olevia (sp) which they sell a ton of. The other one which is what they used on my Greenie is plastic abrasive media which felt almost like sand but without the harsh abrasive properties. It did a great job on the Greenie and did not mar the aluminum. If you want any of this crazy new media I can probably get some from my client as I am going there today to setup their new email hosting.

Mike, thanks for the info, I'm not familiar with the Olevia, I'll have to look that up. Yes, there IS a bunch of other media out there, most of that stuff gets bunched into the term "MEDIA BLASTING" rather than Sandblasting. Glass beads, crushed walnut hulls, baking soda and even Dry Ice pellets are popular.

I only use Aluminum Oxide. It's a little more expensive than Silicon Carbide but it's sharper, cuts faster, doesn't degrade as quickly with use and does exactly what I'm looking for. I can use the same AO 10-15 times before it gets so small that I need to replace it.

Another thing I should have mentioned before, if you decide to go with a pressure pot, BY ALL MEANS run all your media through a sieve before re-using it. It will save allot of aggravation later. THESE are very good sieves, and fit perfectly in the top of a 5 gallon plastic bucket. I filter it right into a storage bucket and put a lid on it. And if you decide to go the pressure pot route, be sure to get one with a top like the one on the left, not the right... it's MUCH easier to fill.

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I was talking with my neigbor about sandblasting, and he has a siphon blaster that he uses on his little compressor with playground sand. So I found a compressor on Craigslist, borrowed his nozzle for 5 minutes and it works great!

My "new" compressor:
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Siphon sandblast nozzle:
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Before:
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Left side blasted in 2 minutes or less:
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