Can someone enlighten a 1st time restorer regarding the secret in not stopping up a sand blast gun? I've tried two different ones at varying pressures... still can't go more than 10 - 20 seconds without stopping up. I have the water traps, etc. in place, media (sand and / or black diamond) is new and / or filtered. Is one brand of gun better than another?
Alex, It is an absolute requirement to have dry air when blasting. Many people
install a water trap at the compressor outlet followed by rubber hose. Not a
good idea. The air coming out of the compressor is quite hot. The air must
travel at least 20' through steel pipe to have a chance to cool down reducing
condensation. Then you need a filtration system. Other than dry air, tip size is
quite important in a siphon system. Also, just as with a pressure system, don't
hold back the trigger. It's full blast or nothing. CFM is also important. Give us
the complete run down on your system please.
I do sift through a screen purchased from one of the suppliers who specialize in such things. PSI runs at ~85 at it's lowest. I'm going to try new media this weekend. Hoping I've just exceeded the recycle limit on my media.
When pressure blasting and the media exceeds it's lifespan it gets real fine and dusty. It also seems like it doesn't work as well or fast. In the cabinet it seems like it stays in there forever and still works. I had a screw become lodged in my pick up tube in the cabinet once, reeked havoc on the operation and tough to figure out.
I use a gun from TP tools in the cabinet with the small orifice nozzles with a 3 horse 60 gal compressor (about 12CFM).
Alex, My blast cabinet is a siphon style. It's a cheap HF type and the original gun was pretty much junk. I replaced it with a Campbell Hausfeld I picked up at my local Tractor Supply Store for about $25. Had to buy the kit to get the gun. I use 3/16 tips, Black Diamond 30/60 media, high flow air connectors, air dryer (steel piping) and filtered air system. I also have about 10 scfm. (and that's marginal). I have no problems with it clogging up.