Maybe my final sandblast question

[Bob Kline]

I went to Harbor Freight and bought a cabinet, a new compressor and a pressure pot. My question concerns the hose from the pot that carries both the grit and the air. Do you bring that heavy hose through the hole and into the cabinet with a gun on the end or do you connect it at the cabinet wall to a more manageable size hose? Once again, thanks.
Bob

[David Takes]

Bob,

You do not want to use a cumbersome hose. I use hose that is used for hydraulic brakes on trucks. It is flexible and lasts forever.

On the end of your hose on the inside of the cabinet you should only have a nozzle. The nozzle can be made of ceramic, tungsten carbide, boron, or a combination. Cheaper is not better as far as nozzles go. I spent $140 for my last nozzle, but it will last for years. If I were to use ceramic or tungsten, I would be replacing them daily or weekly. Tht gets expensive.

The grit ideally should be released with a foot control, not a hand-held gun, especially since you have a pressure pot system.

What are you planning to use for a dust collector?

What blasting media are you planning to use?

Have you checked out some of the sandcarving forums?

[Mike Null]

Pay attention to the nozzle size as well. Depending on what you are doing a smaller size permits greater detail, a larger size is faster but harder to get fine detail.

These nozzles tend to enlarge with use.

[Bob Kline]

Thanks for your help. So far, I have bought 25 lbs. of 80 grit glass beads and also ordered (hasn't arrived) mask material from LaserBits. I plan to use my Jet vacuum system for dust but haven't hooked it up yet. I'm stumped on assembling all the connectors on my Harbor Freight pressure pot -- their pics are terrible and I don't know the connector lingo -- so I'm bringing it to a friend tomorrow to put it together for me. All I intend to use it for is blasting beer mugs. David mentioned that he uses a hose used for hydraulic brakes on trucks. Does that completely replace the heavy hose or do you still run the heavy hose to the side of the cabinet and then attach the hydraulic hose for the inside? So many questions!
Thanks again.
Bob

[Richard Rumancik]

Bob, I know you don't have a Rayzist system but the theory of operation and the connections are probably much the same as for yours. If you take a look at this

http://www.rayzist.com/support/sandcarving_system_product_guide.htm

it might help.

If you don't have the foot control shown then what you would have instead is the hose leaving the "Tee" at the bottom of the pot feeding your gun and there would be some kind of valve on the gun.

This guide also describes how to start and stop your system. This is important. If you close the valves in the wrong order you can make a mess - literally. In one case I had the tank pressurized; later I removed the quick-connector supplying the pressure. The abrasive came shooting out the supply (inlet) end. This could damage the regulator if it gets abrasive inside. I ended up adding a check valve in that line but I haven't actually tested it to see if it works. The point is that you need to follow the sequence carefully.

[Richard Rumancik]

. . . David mentioned that he uses a hose used for hydraulic brakes on trucks. Does that completely replace the heavy hose or do you still run the heavy hose to the side of the cabinet and then attach the hydraulic hose for the inside? . . .

In response to this question: you could do it either way. If you can tolerate the heavy hose up to the blaster then it might be safer. But you need to find/design a good transition fitting between the two diameters of hoses. This might be difficult. If you just use a metal tube to join them there may be blunt ends in the airstream and varying ID's which are not ideal. Smooth transitions are much better. David says the hose wears well so it might be easier to transition at the bottom of the pressure pot to the required ID of the hydraulic hose. But you need to inspect the ID for wear ocassionally and replace if needed.

[Gary Hair]

Bob,
Those glass beads won't do squat for etching glass. You need either aluminum oxide or silicon carbide. For glass you want something 150 mesh or finer, 70 or 80 will eat through glass pretty quickly and won't allow for as much detail.

Gary