steve45
06-20-2008, 11:12 PM
I was using a Harbor Freight 20 pound Abrasive Blaster (item # 40925) yesterday. When I finished blasting, I removed the air supply hose in order to put the blaster away. BAD IDEA! I wasn't thinking. When I released the quick connect coupling, the sand remaining in the tank was blown back out through the air fitting under the pressure remaining in the tank. It did a pretty good job of sandblasting my hand and my leg! Fortunately, I was wearing my goggles and face mask!
I got to wondering why this hadn't happened the previous times I had used the blaster. I think I had run it completely out of blast media each previous use, so when I removed the coupling, only air came out. It made noise, but did no harm. Had I unplugged the air hose from the main supply line, it would have blown media back into the hose (not good, either).
I plan to add ball valve to the inlet of the blaster, so I can seal off the tank when I remove the hose. Pressure can then be bled off through the spray nozzle.
I got to wondering why this hadn't happened the previous times I had used the blaster. I think I had run it completely out of blast media each previous use, so when I removed the coupling, only air came out. It made noise, but did no harm. Had I unplugged the air hose from the main supply line, it would have blown media back into the hose (not good, either).
I plan to add ball valve to the inlet of the blaster, so I can seal off the tank when I remove the hose. Pressure can then be bled off through the spray nozzle.