Spraying Primers-Need Some Help

I’m relatively new to painting but have had pretty good success with a few bc/cc projects I’ve done. My question/problem is with spraying primers. Whenever I spray 2k epoxy or 2k filler primer I always get a rough pebble finish. It wet sands down to smooth but it just seams like it should lay down smoother. I’ve tried raising the gun pressure, lowering the gun pressure, slowing down the gun speed, increasing the gun speed, using different guns, adding reducer and the results are always the same. So I’m sure it’s me. I just don’t know what I’m doing wrong. On the epoxy I used Finishline and Warwick (1.4 tip) guns and the 2k I used the Finishline gun with a 1.8 tip. Any help would be greatly appreciated.

I used to use the same finish line gun. 2 thoughts, 1 check the spec sheet in the primer to make sure you are using the right tip. If so, reduce the primer a bit untill it sprays a bit smoother. Too much and it will gloss over and be too thin.

Good luck. I wound up using a 1.8 tip too.my problem was not enough air volume to feed the gun. I shut it down a bit too and moved closer… combing all the suggested changes worked for me… but the fan was now narrow and time consuming.

P.s. it could just be poor quality primer.

Good luck with your experiments

The 1.4 size tip is too small for spraying primer. technically you are dusting on the primer with that size tip. primer is thick in comparison to base or single stage paint. the suggestion of thinning it out will lead to a smoother application but you would have to apply several coats to get the same results as a 1.8 or 2.0 tip. also check your air horn on the gun or make sure your compressor is flowing enough air to keep up.

Larger tip and thin the primer a tiny bit, not too much especially if it is high build.

So here’s what I found worked the best, after trying a variety of combinations. This is using a Finishline gun with a 1.8 tip and Matrix 2k primer. I added 5% reducer, set the pressure at the gun at 22 psi. I then backed out fan width setting all the way out, then turned it in 2 full turns. Still had a little rough texture but sanded smooth with very little effort.