Painther
Promoted Users
I can't afford a new gun or compressor this time, but I decided I'm gonna bump up the pressure and fluid when I respray to give me a bigger pattern. But ya it's been torture trying to use it for an overall
Tiger striped my first paint job
- Thread starter Painther
- Start date
'68 Coronet R/T
Oldtimer
Your spray gun as two air requirements. First is CFM which is the volume of air the gun needs to function properly, the second is the PSI which is the pressure at which the CFM is needed.
If your spray gun requires 13 CFM at 30 PSI and your compressor only puts out 7 CFM at that pressure, then you are going to have issues. Jacking the pressure up does not increase the volume of air.
I started out with a small compressor and kept having issues, finally broke down and bought a larger, two stage compressor. .
Dean Jenkins
Staff member
That is true if you are spraying continuously - or for longer than the combination of the tank and compressor can supply the required CFM.
But, the combination of the tank and compressor will deliver whatever the CFM the tool demands for some period of time - maybe only a few minutes. Depends on the tank size, compressor CFM output and the tool demand.
See this example:
13 CFM HVLP Gun
30 gallon tank
6.2 CFM compressor output
Tank cutoff pressure 175 PSI
It will supply the gun for 12.2 minutes and recover in 5.5 minutes. That might be sufficient for some situations if you are willing to work around the compressor.
I created this tool to help with this:
compressor sizing guide - Black Diamond
**I am part of the Amazon Associates program. Any purchases made from product links may generate a commission.
blackdiamondblocks.com
Painther
Promoted Users
The specs for the lvlp I'm using says it uses 3-4 cfm, but I'm guessing more like 5. So I'm right at the limit for sure.
When the funds are right I am absolutely going to upgrade my compressor and gun
Painther
Promoted Users
Luckily I was somewhat proactive with the research and connected another large tank, so it doesn't really fluctuate pressure or run out while spraying the whole car. But the trade off is 14-18 psi while spraying my base and that leaves me with a 4 inch fan. So I was thinking of spraying my base a little wetter this time with more psi, I noticed it makes the fan pattern about 2 inches longer. Here's a picture of my setup, excuse the mess. LmaoThat is true if you are spraying continuously - or for longer than the combination of the tank and compressor can supply the required CFM.
But, the combination of the tank and compressor will deliver whatever the CFM the tool demands for some period of time - maybe only a few minutes. Depends on the tank size, compressor CFM output and the tool demand.
See this example:
13 CFM HVLP Gun
30 gallon tank
6.2 CFM compressor output
Tank cutoff pressure 175 PSI
It will supply the gun for 12.2 minutes and recover in 5.5 minutes. That might be sufficient for some situations if you are willing to work around the compressor.
View attachment 39873
I created this tool to help with this:
compressor sizing guide - Black Diamond
**I am part of the Amazon Associates program. Any purchases made from product links may generate a commission.
Dean Jenkins
Staff member
What PSI does the gun instructions recommend?
Painther
Promoted Users
It says in the manual 29-50 psi. I sprayed the clear at 30 but the base at 18-20
RosharonRooster
Promoted Users
i wish the cars i work on were that small.
If you can't upgrade your equipment I would wait until you can. Meanwhile enjoy your car some.
Treeslayer
Mike
would you paint with a towable compressor? i been after one for years, just for blasting. they bring a lot at sales. almost had one of those half a ford engine set ups once but got outbid at the last second. i am not a skilled bidder lol.
If you setup your lines correctly and could have it outside or in an enclosed or partially enclosed area outside of the workplace it should do fine. Noisy though I would imagine