Need irgent help. HVLP & LVLP. CANNOT differentiate

Any questions about tools or supplies. Post your compressor/gun questions here.



Top Contributor
Posts: 5021
Joined: Tue Sep 16, 2008 1:17 pm
Location: Pahrump NV.
Country:
USA
PostPosted: Tue Jan 12, 2021 11:34 am
Moderncc wrote:Thank you so much friends. But these are the most expensive local made guns I can get hold of in my area. Other guns which most of the shops here use cost not more than 20 bucks. I tried to buy what was the costliest on the shelf.

Anyways, I guess I NEED to buy a bigger compressor with atleast 10 cfm of power.


Your local Auto body shops are using guns that dont cost any more than $20?????
I find that EXTREMELY hard to believe!!!!!
As far as Buying a Good Gun look to the Internet TCP global sells many Hi quality guns at reasonable prices. https://tcpglobal.com/pages/spray-guns-type
There are many many more!

10 CFM is NOTHING! You need at least 12-17 CFM @ 90 PSI or greater!

Air compressors will have multiple ratings :
Free air CFM
This is what the pump will produce with no load on it as if it had no Tank.

X CFM @ 40 psi
This is the amount of air the compressor air pump can make with a 40 PSI back pressure
from the tank.

X CFM @ 90 PSI
This the amount of air made at working pressure! 90 PSI in the Tank backing up on the Pumps output. And seriously the only rating you need to be concerned with! Its the only number that matters! None of the other numbers matter! Not Tank size Not HP rating The Bigger the number @ 90 psi the better! This is the pumps true ability to do work the bigger the better! !

There are very few Compressor pump MFG that will give you a rating at 175 PSI very few!

If you look at very many compressors and there detailed specs you will find numbers all over the place with these ratings, Your only interested in ONE! CFM @ 90 psi!!!!!!!!!!!!
If the MFG doesnt post this number its because its so small and shows that the Air pump is Junk and not up to doing real work!

Because ALL air tools are designed to work at 90 PSI I don't care what tool it is! ALL air tools need at least 90 PSI to operate correctly even your Paint gun!
Your Paint gun is designed to work with an Air pressure regulator that operates off of at least 90 PSI!
Which brings up another point I wanted to make about AIr Pressure regulators, There are Many many on the market they regulate your tank pressure down to what you need at your tool, There are good ones on the Market and their are a lot of cheap JUNK ones on the market just like anything else these days. You get what you pay for.
But here again an Air pressure regulator Is an Air tool!!!! its designed to do a Job at at-least 90 psi! to work correctly.

So if your compressor only makes 2-3 CFM @90 PSI you can only use tools that consume 2-3 psi to prevent pressure fluctuations. If and your using tools that consume 8-12 CFM your Pump will be constantly be running trying to keep up with a Job or demand which is more than it was designed to do.

So I hope I made it clear about the CFM rating at 40 PSI It means absolutely NOTHING its an Advertising gimmick to make the compressor look bigger and better than it is! Nothing more. No air tools work correctly at 40 psi not even your air pressure regulator.

The pressure difference you explained between your two guns did not make a lot of sense to me, I chocked it up to tank pressure already being depleted or a Malfunctioning air pressure regulator myself.
As you have tank pressure and regulated pressure,If the Tank pressure is constant the change in regulated pressure can only be explained by air flow or CFM flow rate change.
If your getting a Bigger pressure drop that gun consumes more air requiring you to increase the desired working pressure.
That would suggest that your lVLP is consuming more air than the other gun.
Last edited by Doright on Tue Jan 12, 2021 2:50 pm, edited 1 time in total.
Dennis Barnett
A&P Mechanic, FCC General radio Telephone Operator
Line Maintenance A&P Mechanic and MOC Tech specialist.

User avatar

Top Contributor
Posts: 3667
Joined: Wed Sep 07, 2005 9:59 am
Location: Louisville, KY
Country:
USA
PostPosted: Tue Jan 12, 2021 2:03 pm
Doright wrote:
Moderncc wrote: 1.2 Fluid tip is only good for spraying heavy Poly primmer's and under coatings!
And may explain pressure differences a little as well it may have a special air cap dedicated to a 1.2 fluid tip? again I am not sure i dont anything about those particular guns


What? That's the smallest tip I've ever seen.
I use a 2.0 for poly and it's on the small side.
1.3 to 1.4 for clears and base are normal.
JC

(It's not custom painting-it's custom sanding)



Top Contributor
Posts: 5021
Joined: Tue Sep 16, 2008 1:17 pm
Location: Pahrump NV.
Country:
USA
PostPosted: Tue Jan 12, 2021 2:45 pm
JCCLARK wrote:
Doright wrote:
Moderncc wrote: 1.2 Fluid tip is only good for spraying heavy Poly primmer's and under coatings!
And may explain pressure differences a little as well it may have a special air cap dedicated to a 1.2 fluid tip? again I am not sure i dont anything about those particular guns


What? That's the smallest tip I've ever seen.
I use a 2.0 for poly and it's on the small side.
1.3 to 1.4 for clears and base are normal.


UH I think I had a MAJOR BRAIN FART! mainly because its the smallest I seen myself I have a 1.3 though? I duno why I was thinking opposite BUT Your right, I was thinking 2.0 2.2 your right I feel soo stupid right now! I hate to admit it but I am getting old what can I say?

:whoops: :rolleyes: :shocked: :knockout: :rotfl:

I deleted it from the post :whoops:
Dennis Barnett
A&P Mechanic, FCC General radio Telephone Operator
Line Maintenance A&P Mechanic and MOC Tech specialist.
Previous

Return to Tools and Supplies

Who is online

Users browsing this forum: No registered users and 18 guests