Modern Vespa

I am about to shoot some two-part epoxy primer and the spec sheet calls for a 1.4-1.6 nozzle and, for conventional guns, 45-55 lbs. gun pressure. For HVLP guns, which I use, it says 5-8 lbs. Really?
Thanks.

Really. HVLP is like spraying with a rattle can. Takes a little getting used to, but once you believe, you'll be a believer.

5-8 lbs just seems very low but I'll give it a try..

Thanks CM. I have painted 7 cars and 6 scooters over the years starting with siphon guns and then top-loaded HVLP. I do realize that the low pressure is at the nozzle. I'll give it a go. Wish me luck.

Your 5-8 psi is what it should be at the cap. Your gun should say another psi range going in. My primer gun uses 43 psi to get 10 at the cap. 30 for my mini and 24 for my finish gun. Are you using the primer as a sealer or high build? I use a 1.4 tip for sealer and a 1.8 for high build. Pressure into the gun stays the same.

Check your pattern and flow on something smooth before doing the real deal. You can adjust the pressure to suit the volume. It's all based on the gun you're using.

Cheapo gun for this sealer. I'll do all the filler on top of that and then a high build ( which I have also never used before) on that. I'll set the pressure at the gauge on the gun to flow under 10 and see how it goes. I don't think it's too critical at this stage.

My lvlp gun takes a minimum of 15 psi into the gun. Im betting you'll need at least 30 something psi for your cheapo hvlp.

Here's the cap on my lvlp and the inlet pressure on my mini. The cap pressures are almost always close to 10 psi. I wouldn't steer you wrong.

Here's my arsenal. The two on the right are for shooting metalflake. Except the lvlp in the middle, the rest need between 29 and 45 psi to get 10 psi at the cap. For what it's worth.

Listen to Rob. The 5-8 psi is what's coming out. Adjust it on the gun.

Cheapo gun was garbage. Needle packing leaked and I didn't feel like messing with it so I switched to the better one and it all worked out fine. Thanks.

I upgraded to a DeVilbis gun, though not a high end model like Rob's, for the Riverside and it definitely shot a nice coat of paint once I got the hang of it.

This is my dedicated primer gun. It came with a 1.4 and 1.8. Couldn't be happier. I think it was $130. It also came with a regulator.

I like that little regulator.