I bought this sandblaster, http://www.harborfreight.com/cpi/cta...emnumber=38375
and i havent been able to get it to work. First thing i tried was some black beauty we had lying around, and that clogged even the largest tip. I tried playground sand, but it still cloggs. also, i can get a constant air pressure, and i dont even know waht psi to set my compressor to. Any recomendations as to what sand to use, and what pressure to sandblast at?

 

I used to have a large cabinet with a vacuum and light. I just ran it full pressure. The problem I found was humidity. I was using glass and it would clog unless I kept a light on in the cabinet to keep the glass dry.

 

You need dry silica sand and a large volume of high pressure air. If your compressor is small you will have a very short window of pressure to blast properly. You can adjust the sand needed on most pots. Silica sand and powder coating do not mix, a plastic media works best.

 

I had the same problem with mine. The black silica carbide I bought was just too coarse and clogs the tips no matter what size. Finally tried silica sand and it too would clog. Even though I was sure it was good and dry, having too much moisture content turned out to be the problem. I found that if would spread it out on a tarp and shallow in buckets for at least a week ahead of time then it would work fine. Doing that with the silica carbide didn't do any good. It's just too coarse.

 

I put the sandblast material in a large crock pot and turned it on low to dry the sand. If you don't hear from me again, it means my wife read the boards and did me in.

 

Most of these pressure blasters have a sand outlet valve that regulates the amount of sand entering the air stream. The one I used had it at the bottom of the tank. I had similar problems, and finally played with it by cutting the sand flow way back to almost nothing, then increasing it gradually for the best blast. Might be worth a try.

 

I have the 40 lb. version of the Harbor Freight Abrasive Blaster. I spread sand from my yard on a sheet of tin and let it dry in the sun and then screen it through a homemade seive (made from ordinary window screen wire). Works well with my 2.5 hp compressor. I have a water separator on the air line. When I use playground sand from Lowe's or Home Depot I screen it too, but it has always been plenty dry to use out of the bag.

 

I've never had any problems with the sand being too damp, but you really need to screen it. Black Beauty is WAY too large for any home applications, and even an occasional small stone will plug things up nicely. Just screen regular playground sand through a window screen, and you should be good to go. I wouldn't regularly blast with anything less than a 30gal compressor with less than 12-13cfm at 90psi, or you're just asking for it to burn up.

 

Make sure you use proper breathing gear if you use sand to avoid lung damage. Of course you need to use the proper gear with any medium.

 

all my books says minimun of 7cfm@80psi the larger tips require flows of 15and20 cfm,I have been looking at compressors and a 5 hp 30 gal will barely make the minimun. good luck

 

One thing not mentioned above is using a water trap where the air line hooks up. The condensation from the compressed air was the problem I had with clogging. We attached a trap to the sand blaster and I've had much better luck.

 

My compressor is a 60 gallon, with 14 cfm @90psi. I have a water seperater at the compresser and at the blaster. I think i just need to screen the sand, because a lot of pebbles were getting caught at the tip and clogging it.

 

My boss bought one of those from Harbor Freight last summer, to try on a large blasting job we had. We found it totally inadequate to our purposes and wound up buying an industrial blaster with a 350 CFM diesel compressor. But we did learn a few things: First of all, it's hard to beat real sandblasting sand. We tried playground sand, but the variety of sizes of the media was always plugging things up. We were doing production work and didn't have time to fool with drying out damp sand and unplugging clogged nozzles and valves. We wound up with #30 blasting sand, available at the local lumber store in 100LB. bags, that have an inner plastic liner to act as a vapor barrier. About 7 bucks a bag.
If you can maintain that 90 psi, you should do okay. Until we got the big compressor I hooked two smaller compressors into a common tank, but we'd still have some downtime while waiting for the pressure to rebuild. As krehmkej said, we got our best results by closing the sand valve and gradually opening it till we got a good flow of sand mixed into the airflow. One problem was that when you started blasting, you'd get a large useless flow of straight sand till the hose cleared out after you had stopped to refill or rest the compressors
Watch those cheap valves and hoses on that blaster. We wore out two valves, the sand winds up eating through the sides, and the hose didn't hold up too well either. Popped a few times. For small, light duty jobs, I still use it, and it's okay. I'd buy one for home use, but I really got spoiled by the big one, blasted my headers for my Ranger swap in about three minutes. Anyway, good luck with it! -TD

 

I bought the #40 blaster as well, I've run aluminum oxide and the #50lb bag of silica sand through it with no problems in clogging. Do get a good respirator though, Harbor Freight only provides that cloth hood and that could be dangerous, if you breath in the dust.

If you don't have or cannot afford an upright 220V 60-80gal *** kickin compressor, you may have to do what I did: I have a 25gal craftsman 115V air compressor that worked too hard at keeping constant pressure in the blast tank, so I Tee'd the air inlet and supplemented the craftsman compressor with my dual tank portable compressor from Checker Auto, it maxes at about 125psi, but since I blast at 70psi, problem solved. Both compressors together can keep constant tank pressure in the blaster without working too hard.

Just make sure the compressors are not in the blast area, too much dust is not good for the filters.

 

Thanks for the info. I did finally get the playground sand to work, i just run it through a window screen before i put it in the blaster. The blaster stays at a constant 90psi. I run the second largest tip with the sand only half on. It worked great for doing the front end parts for my truck and my brother used it on the wheels for his formula