gun spitting?

[randygrapes218]

i have a gun from another company, with the air hooked up i a doing a part and very often it spits alot of powder out, so much it clumps on the part? i am runing about 18lbs of pressure at the compressor and regulate it more with the gun. for some reason the trigger doesnt work, the only way to stop it from spraying powder is to turn down the screw on the gun? is my gun messed up ? also i have 1 spot a part the has too much powder because the gun gun did this, (the rest of the part came out great) it is chrome, can i just wet sand it to blend? thanks for any replies... randy

[jtagger19]

screw in the plastic screw at the bottom of the gun

[randygrapes218]

what does that screw do? now that you mention it, before i sprayed this part was the first time i took that screw out.

[jagboy69]

I just burnt up my HF gun last week... It lasted about 4 months, just long enough to be out of warranty. So I bought another one and bought the 2yr free replacement deal for 9.99. Worth it in my opinion. The plastic discs are meant to be screwed in and out. You will notice they gave you three of them too. Depending on where you have the thingy screwed in, will change the size of the circle being sprayed. Up tight for large areas, and out for smaller areas... (I think) maybe the other way. Screw with it and see what happens. If you are talking about the metal screw near the air hose, this fine tunes the amount of air. I never messed with mine, I use a regulator on my air line.

[customandsound]

Buy one from caswell!!!!!!!

[pdeinc]

Spitting is caused when powder clumps in the barrel, and this happens more in a high humidity environment. If you can't lower the humidity where you're spraying, the only alternative I can think of is using a higher pressure in the gun so that powder doesn't have an opportunity to build up in the barrel.

As for the trigger issue, it's not uncommon. Best thing is to frequently disassemble and clean the needle valve and not overtighten the gland nut that seals the needle against leakage. You may add a touch of dry lubricant to this seal as well.

[randygrapes218]

thanks for the replies so far... i was wondering what the little plastic screw on the bottom does? as far as humidity goes i am in massachusetts and it is very dry out right now so i dont think that is my problem.. believe me if this gun dies in 4 months i WILL be buying one from caswell!!!!

[Zpider]

I use slightly over 2 bars pressure, under that the gun dont flow correctly. Regarding the trigger, i loosened the screw around the pin a bit and since that it seems to work as it should.