Well, I've been spraying for a few years on the side, and have come to a hurdle I have been having trouble figuring out! Im repairing a door for my mothers camry, I spot putty some dings and whatnot, then primered using painters pride black primer, then went to seal with my matrix primer sealer(epoxy) and my gun (same one as I sprayed the primer perfectly) is spitting out clumps of the sealer and nearly ruined all my work. Im using a 1.3mm tip iwata ernest at ~20psi. I then tried my cheaper non epoxy painters pride sealer (permixed) and the same gun does the same spitting/ clumping! Any help? Thanks guys!

Have you been straining the material as you pour it into the gun?

Also, the gun probably has some clumped material or buildup inside.

If you haven't already, take apart the gun and clean the fluid passages, needle, nozzle, etc. Get a gun cleaning kit and use lacquer thinner to thoroughly clean out the gun.

20 psi? Sounds a little low to me.

Still havent figured it out.. I bought a 1.8mm finex 3000 to spray this matrix 2k sealer, and at 35 psi to the trigger (depressed) im still getting clumps spit out of sealer... no idea why.. shouldnt be this difficult, any thoughts?

Start out by cleaning your gun. I am thinking that you have some old buildup that is coming out of your gun. Then go back and shoot some test panels and see if you are having any more issues. I would also look at your sealers and see how old they are, and check your activators. Strain your activator into a clean cup and see if you have any clumps or anything unusual about it.

Chuck

How long has the product been sitting before being used?
How long has it been sitting with the lid sealed after opening it the first time? Its a good idea to use products within a year after opening them, and keep the temp stable around 60F-75F, if possible. Too cold and it can make condensation form inside the can.

If you have a jobber who is very slow to move product, sometimes you will get a batch that has a lot of clumps or chunks at the bottom. Extra shaking and stirring can help in most cases, but in other cases its best to return the batch and show the jobber what you are running into.

If you look at the activator in the can and swirl it around, do you see little seeds/beads? If you see beads of hard material in your activator, the activator has spoiled and needs to be replaced.
Spoiled activator will have little "seeds" or balls of dried up activator that will never mix in or properly activate the product.

Just some tips that might help you get pointed in the right direction, if it isn't a gun issue.