Sorry if this has already discussed, but I didn't see it exactly as it fits my application.

I have a gravity feed HVLP gun. The paint container rests on TOP of the gun.
Reading the manual for the gun, it recommend to set the regulator at 40-60 PSI, and then reference the paint spec sheet for dialing in.
My primer spec sheet recommends 5-7 PSI at the cap, and the paint spec sheet states 6-8 PSI, and clear coat HVLP air pressure set to 8-10 on the spec sheet.

I set my regulator to 40 PSI, and I don't see how I get these sub 10 PSI values on my gun. I purchased an extra gage and hooked it up to a t-fitting with quick disconnects (reading from anohter thread recommendatin on dialing in HVLP gun). The gage right below my gun handle reads 40 PSI, just like the regulator.

Am I missing something here ? My spec sheet for the primer lists 20-30 for gravity feed gun. Am I suppoled to set the gravity feed gun spec at 20-30 even though it is HVLP ?

Freshpaint wrote:Sorry if this has already discussed, but I didn't see it exactly as it fits my application.

I have a gravity feed HVLP gun. The paint container rests on TOP of the gun.
Reading the manual for the gun, it recommend to set the regulator at 40-60 PSI, and then reference the paint spec sheet for dialing in.
My primer spec sheet recommends 5-7 PSI at the cap, and the paint spec sheet states 6-8 PSI, and clear coat HVLP air pressure set to 8-10 on the spec sheet.

I set my regulator to 40 PSI, and I don't see how I get these sub 10 PSI values on my gun. I purchased an extra gage and hooked it up to a t-fitting with quick disconnects (reading from anohter thread recommendatin on dialing in HVLP gun). The gage right below my gun handle reads 40 PSI, just like the regulator.

Am I missing something here ? My spec sheet for the primer lists 20-30 for gravity feed gun. Am I suppoled to set the gravity feed gun spec at 20-30 even though it is HVLP ?

See you're not getting flooded with responses so let me address the issues you ask about. Your gun, cup on top is a gravity feed gun as it doesn't take a given amount of air pressure and or flow to pull the paint from the cup to the nozzle like a siphon feed gun does so yes, follow the specs for gravity feed. HVLP is an acronym for High Volume Low Pressure which has to do with what it takes for the gun to atomize and spray the paint properly. Forget the 10 psi at the cap info, that is a pressure you can't measure with your gauge and is there for meeting standards set by the government and apply mostly to commercial paint shops. Set your inlet pressure at the handle with your gauge per the 20-30 psi and then tape some masking paper on the wall and shot some primer and make any pressure, fan pattern and fluid flow adjustments till you get the product applying the way you like / want it. Hope this help a little and good luck / Coy

CaBoy Coy is correct. The gun sounds like a standard gravity feed spray gun. HVLP relates to the maximum air pressure allowed internally at the cap (10psi).
You don't specify which brand or model of gun you are using, nor which needle/cap/tip size, so I can only give you general guidelines on usage.
Most popular well-known HVLP gravity feed spray guns run optimally at pressures ranging from 21 to 30 psi. If you have a name-brand spray gun (DeVilbiss, Sata, Iwata, Sagola, Binks, Sharpe, etc.) then there should be a chart from that mfgr. that tells you what the optimal setting is (in terms of equipment and pressure) for each primer/base/clear. If the spray gun mfgr. doesn't have the info., then the paint company might.
Hope this helps a little bit. Maybe with some more information, we could be more specific.

thanks for the replies here. It confirmed what I was thinking. I wounnd up setting my gun to the paint spec sheet PSI for gravity feed gun. Once I dialed in my gun a little I figured it was good to go.