Pressure sandblaster from propane tank

[Sberry]

I used a radius arm grommet from a ford pickup. pull it up to seal and when the pressure drops it opens. Used pressure washer hose for the blast hose and 1/8 xh pipe nipples for the blast nozzles.
There is a valve on the bottom to regulate the sand and I made long wand. I didn't use a dead man.

[Joe from N.Y.]

hey, i made a blaster a few months back, it is similar to yours, the filler port is the same, 2" nipple and cap. how do you have the inner tube sealing the cap? could you take a pic? mines leaking, i tried a few diff ways to place the tube but it still leaks.
thanks

I know you solved your problem, but i will post this here for the benefit of those who might have the same question:

mine is not a perfect seal. It is good, but there is a slight air leak. It never bothered me enough to look any further into fixing it. I used a rubber circle of inner tube to fit in the cap.

[jerems]

Dope it

Smear some pipe dope on the threads - or teflon tape. The nipple probably doesn't butt up against the cap so the tube gasket won't help a lot.

Great job. Great idea. I'll put that on my someday list.

[Joe from N.Y.]

Smear some pipe dope on the threads - or teflon tape. The nipple probably doesn't butt up against the cap so the tube gasket won't help a lot.

Great job. Great idea. I'll put that on my someday list.

Yeah, i never looked close until i took this photo this week, the nipple does not seat up against the rubber piece, i guess that is why i get a leak. i don't want to use dope on the threads, the sand will stick when i fill through the nipple and will make like a lapping compound and wear the threads over time. i think i will put probably a half of a tube of latex or silicone sealant caulking compound in the bottom of the cap and let it harden to like rubber. that would most likely give me a better seal. Thanks

[Tim B]

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

[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]

Sandblaster

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