Trying to sandblast aluminum

[lhiga]

I need some help.
I fabricated my sandblast pot, got some glass bead #12 (140/230) then started sandblasting my piece. The glass went through the pot fine on the first round, but after I refilled my pot with the previously used glass and tried to use it again I started running into problems where the sand acted either stuck or the air would just burrow a hole through the sand and all I would get out of my gun was air.

I think the problem is the humidity here. Our RH is 60-70% so I think this is moisening the sand enough to where the glass is clumping together. And because I am using such a fine grit for it to clump or try to stay together in one big mass it would not take much moisture.

I have a air/water separator on the output of my compressor. I am using a 7/64" nozzle. The nozzle size and glass bead grit size was chosen because I have a small compressor and I don't want to go out and purchase another compressor.

This is the first time I am sandblasting anything so all help would be greatly appreciated.

[fly]

Take a leather glove and place it over the nozzle blocking the hole and cause a back flow to flush out the suction of the pot. You probley have some trash in the pot. Take two window screens and filter you beeds when you refill the pot..