Pressure sandblaster from propane tank

[cws612]

you do realize that we are talking about welding on a pressure vessel with incredibly questionable welds shown so far! please procede with utmost caution as you are creating a bomb for the hobbyist.

[~willy]

I've built a few of these back in the 80's. They are a very useful tool, especially prepping material for welding.

I extended the arm of the bottom feed valve so that it can be nudged w/ a foot or is easier to adjust while wearing gloves.

I have built a few of these and never used a rubber gasket. It could be that your pipe fitting warped from welding.

One needs to take precautions when cutting or welding on a propane tank; not for the amateur. Freon tanks also work and are more portable.

When using these you need a supply of DRY air. Moisture will cause sand to clog.

Keep in mind that there are inherent dangers in welding and danger in sandblasting.
Sandblasting can cause silicosis, and many novice types will not use proper ventilation/respiration precautions.
By the way, you'd be surprised at the damage you can do to equipment from dust particles floating in the air or how far the sand can travel and still damage automotive glass. If it can damage automotive glass..... it may also pose a rick to your eyes as well. Use proper safety equipment. You wouldn't weld without a welding helmet; RIGHT.... ?
A word to the wise....

Willy

[Jim-TX]

you do realize that we are talking about welding on a pressure vessel with incredibly questionable welds shown so far! please procede with utmost caution as you are creating a bomb for the hobbyist.

My thoughts exactly. It works but it's a bomb.

[PTsideshow]

All of the import type models use an O-ring around the pipe filler neck for a seal. DRY air is more important for free following media.
Followed by a clear hood window and a great respirator.
As silicious effect on your lungs is cumulative, and it doesn't take much to cause you problems. And end up joining the oxy bottle brigade at Wally World.

And if you are using the deadman type import valves, HF is now selling the complete unit handle part for around $15.00 And if you are having a hard time finding the replacement rubber block with the alloy plate Tractor Supply sells them under their job smart brand.
Abrasive Blasting Deadman Valve with 4 Ceramic Nozzles HF Item # 92189

And one final thing, during the high humidity months, Don't fill the tank all the way up. And empty the media tank between uses if you won't be blasting weekly. As it will cake up at the outlet and in the fittings at the outlet/hose area.

[billybee60]

I have a similar kind of rig and found that a tank pressure of 10-20 psi seems to feed a good quanity of sand. However it may be too much. What pressure setting are you using on the tank? Does the sand grit get into the feed valve you have on the tank outlet? I don't have a valve like that. Does it work well to control the amount of sand?

[Sberry]

very cool project! have you ever thought of using 2 20lb bottles and cutting one in 1/2 and cutting the ends off another the take the 2 1/2 pieces and weld them on the section you cut the ends off then you will have more capcity. just a thought

How about a 40# bottle, would save the cutting/weld.

[Tim B]

How about a 40# bottle, would save the cutting/weld.

i can't find a steel one

[Bearston]

Nice Bomb. With the quality of those welds, keep your children away from that unit. This is a PRESSURE VESSEL. Unless you've had training for welding on pressure vessels, I wouldn't dare weld on any pressure tank without training, especially a repurposed propane tank. At least get your bomb hydro tested, I doubt that those questionable welds will hold up and over time expect them to fail. It may work once, twice or even 10 times, but be prepared for that thing to blow up and when it does, the shrapnel flies, remember your dealing with COMPRESSED air If you don't care about yourself, that's ok, just don't subject your kids or friends to it. Do yourself a favour and go get a professionally made unit. The $100 that you're saving could cost you or your loved ones your an eye, an arm, leg or even your life. Don't mess with compressed air, even 10 psi can cause an incredible ammount of damage. And then come the lawsuits....

[H80N]

Doncha just love it when someone digs up an ancient thread and gets into a debate with it????...........

[Bearston]

glad that YOU approve