[vmeng]

Dear members,
I'm making a portable sandblasting machine for cleaning all my metal parts.The abrasive I use is steel grit.But the steel grit does not vomit out continuously.I did changed the size of the hole from grit tank to the air supply pipe ,but still can not improve.

Please give me some advise to fix this problem.

Thank you

Vmeng

 

[slamdvw]

try making an air bleed where the gun can suck air in and mix it with the abrasive.

 

[digr]

try making an air bleed where the gun can suck air in and mix it with the abrasive.

Here is a factory drawing of a smaller metering valve for a cabinet blaster that I made that works well. It would have to be made larger to fit your needs.

 

[Thomas Clark]

It depends is it a pressure tank or a draw blaster? A draw blaster uses a sand or glass beads witch are much lighter then steel shot . The steel shot maybe to big to move ,thus requiering lots of air pressure to move it. A pressure tank has the sand and air pressure together. It forces the sand out at the same time the tank acts like an hour glass helping the flow rate more efficently. Becareful making your own pressure tank, you could shoot your eye out.

 

[asemaster]

if it's a siphon type you need to have a hole in the pickup tube about an inch above the end , this is known as a ventury just like in a carb. you need this to airate the meedia to get it to flow.

 

[Ries]

Most steel shot machines dont use compressed air- they actually throw the steel shot physically, as in the Wheelabrator machines.

I used to pay a big shop to do some grit blasting, with steel grit. They used a row of 175 hp compressors- at least 3 of em- to charge a 2000 gallon or so receiver tank, and the steel grit came out of a 1 1/2" diameter hose.

In other words, heavy media needs lots and lots of air, huge CFM's- 50 or 100 is not uncommon. If you are trying to do it with a tiny little "5hp" compressor, that could be why.

Copy the designs from TP Tools- they make sandblasters that work.
http://www.tptools.com/

 

[weldeyes]

Hope this helps

All home made.

http://www.scribd.com/doc/4362608/SandBlaster :waving:

 

[chikinguy]

Hope this helps

All home made.

http://www.scribd.com/doc/4362608/SandBlaster :waving:

This is great!:cool2:

 

[ElGuapo]

Get a good water separator. Any water will let the abrasive material clog.
Don't forget to aerate the grit. It needs airspeed, when it clogs it's over.