Where to go from here? Moisture pimples

Scratch that just read he’s already using an lph not sure how much less cfm you can get with that. Just throwing things out there. I know when I was young and broke(still feel broke just older) I did some pretty good paint jobs with some pretty inadequate equipment and cheap material. Wondering if the cheap material was less forgiving. Such is life. The better we try and do things the more problems we have lol.
 
Thanks, Maybe I'll stick to doing panel by panel? is a lower solids clear like euro or production more low CFM friendly?

the part I'm not understanding about CFM versus PSI is isn't the paint gun a fixed orifice size? if you can blow through that paint gun with trigger all the way open and the pressure never drops below 100 PSI shouldn't that mean I have enough CFM? I'll definitely be taking a close look at this.
Your compressor probably isn’t making enough CFM to begin with. If it’s a 30 gallon it probably has a small motor and pump. The CFM is the volume of air your compressor is producing. Any compressor can make high pressure, but it might not be capable of making a lot of air volume. What you should do that will help is to put larger air fittings on all of your air lines. This provides less restriction for the overall airflow as well. I use the big 3/8 inch fittings.

When you did two panels and one panel looked fine and the other did not, is the one that looked bad the second panel you did by chance? Because if it is, then that is your clue. Almost like once your compressor started running longer then you started seeing worse quality.
 
So many marginal things going on here. Low over nite temperatures. Epoxy reduced only 15% for sealer. Undersized compressor.

Time to clean things up and start following recommended processes imho.

Don
thanks for the feedback everyone, I really appreciate it, I'm a novice so it's easy for me to overlook things that are obvious to pros.
the epoxy was sprayed in Sept, 2 months ago so I think that's ok.
I am using an LPH and painting half of a very small sports car slowly, just doing the quarters not letting the wall drop under 100psi. before I move onto the hood and doors I wait for the compressor to catch up.
It's cold outside here so I preheat the garage to 75F, panels were at 72F when I start spraying, cooling to 66F on the last coat. after that the heater is back on and cured overnight at 75F.

Im thankful for all the support from Barry and the SPI materials are quality, just tough with my marginal equipment. I'm learning a lot as I go.

Here's my Ford I sprayed with Omni and cheap clear, it turned out great.
20211019_144405.jpg

Here's where I'm at with SPI red and SPI uv clear
20221123_181906.jpg
20221123_181921.jpg
20221123_205401.jpg

I am glad the uv clear lays enough mils down that I can correct stuff easily, but it's hard to buff out jambs
 
I'll repeat my previous post. You need a bigger compressor. I would be surprised if your compressor puts out more than 8 or 9 cfm. 15 cfm really is the bare minimum.
It's not about pressure, it's volume (CFM) that is causing the issue. Pressure and volume are independent of each other. Blow through a straw, you will have high pressure but little volume. Blow through a 2" pipe, you will have low pressure but more volume. Your compressor probably isn't able to provide the amount of volume (CFM) that you need with the gun you are using. Therefore you get the CO2 gassing iso clumping because you don't have enough volume to break up the paint (as per Barry's post above). Get a bigger compressor and the issue will go away.
 
Curious where you have set the air valve at the base of the LPH400. It might be choked off. I run mine wide open. If it’s choked off it might explain what you are seeing.

Don
 
thanks for the feedback everyone, I really appreciate it, I'm a novice so it's easy for me to overlook things that are obvious to pros.
the epoxy was sprayed in Sept, 2 months ago so I think that's ok.
I am using an LPH and painting half of a very small sports car slowly, just doing the quarters not letting the wall drop under 100psi. before I move onto the hood and doors I wait for the compressor to catch up.
It's cold outside here so I preheat the garage to 75F, panels were at 72F when I start spraying, cooling to 66F on the last coat. after that the heater is back on and cured overnight at 75F.

Im thankful for all the support from Barry and the SPI materials are quality, just tough with my marginal equipment. I'm learning a lot as I go.

Here's my Ford I sprayed with Omni and cheap clear, it turned out great.
View attachment 23211

Here's where I'm at with SPI red and SPI uv clear
View attachment 23212
View attachment 23213
View attachment 23214

I am glad the uv clear lays enough mils down that I can correct stuff easily, but it's hard to buff out jambs
Your PSI is not the same as your volume.
 
So many marginal things going on here. Low over nite temperatures. Epoxy reduced only 15% for sealer. Undersized compressor.

Time to clean things up and start following recommended processes imho.

Don
Why are you thinking the epoxy reduction matters? I’ve never actually reduced epoxy as a sealer. I spray it unreduced and wet sand 600.
 
Why are you thinking the epoxy reduction matters? I’ve never actually reduced epoxy as a sealer. I spray it unreduced and wet sand 600.
Because he sprayed base on 15% reduced epoxy next day after sitting in a cold garage overnight. 30% reduction for next day, 50% same day is the guideline afaik. Temperature guidelines also need to be followed. Your case is completely different.

My point is a lot of things are marginal.
 
You can check your local Craigslist, marketplace, etc for a 80 gallon. Or swing by TSC and grab a IR 80 gallon. I have no idea what your budget allows. But both those ideas are on the cheaper side.
 
You can check your local Craigslist, marketplace, etc for a 80 gallon. Or swing by TSC and grab a IR 80 gallon. I have no idea what your budget allows. But both those ideas are on the cheaper side.
I have the IR 60 gallon two stage unit from TSC, very happy with it
 
Agree with that statement.
But, if a tool like a spray gun consumes a given CFM and the PSI at the tool is continuously maintained, doesn't that mean the compressor is delivering the needed CFM?
There seems to be a bit of magic attributed to pressure and volume, but I am going to side with you and say yes, though there will will be fluctuations due to the cycling of the pump. If you want to know if a given compressor can handle a given tool, just run the tool at the intended air consumption continuously and see if the pump can keep up once it kicks on. If the air pressure continues to decay when the pump is running and the tool is running, there is not enough pump output. It doesn't really have to be more complicated than that.
 
With his gun it requires almost 10 CFM. His compressor is probably maxed out at 8 or maybe 9, if the rated CFM is to be believed which is doubtful. Then factor in the long piping run, more than likely using undersize piping,. (50 feet needs 3/4 min) and it is highly unlikely the gun is getting the air volume it needs. Evidenced by his issues.
Here is a typical 30 gallon compressor.

It's rated at 6.2 SCFM at 40 PSI and 5.3 SCFM at 90 PSI. Tell me how that is going to work with any HVLP other than a mini gun?

Put it another way. Imagine a distance runner in the last lap of a race. Just because he is breathing the maximum amount that he can, doesn't mean he is getting the volume of oxygen that he needs. So he is in an anaerobic state. Or a guy with asthma is breathing as much as he can but isn't getting the oxygen that he needs. Using an HVLP with an undersized compressor is like the above scenarios. May seem like it's working but it isn't functioning fully.
 
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There are a lot of low solids clears out there to choose from.
They are impossible to solvent pop, orange peel, or run.
The lower the solids, the more child-proof they are, but if an insurance shop starts using them, they usually see a daily driver in 2 to 3 months that they did and stop using that clear.
Some shops, when as they say we have to do lot jobs for a used car dealer they will reduce the 5000 4.1.3, and if they dont need to buff, stop at one wet coat.
I hear all the time the car lot will say to make it last 30 days so I can sell the car.
 
OP says his pressure is holding despite his setup doesn’t work on paper. I think it may be because he has choked off his gun using the valve on his Iwata gun. That would lower his air consumption and lead to his issues that Barry is attributing to low air. Just a theory….

Don
 
With his gun it requires almost 10 CFM. His compressor is probably maxed out at 8 or maybe 9, if the rated CFM is to be believed which is doubtful. Then factor in the long piping run, more than likely using undersize piping,. (50 feet needs 3/4 min) and it is highly unlikely the gun is getting the air volume it needs. Evidenced by his issues.
Here is a typical 30 gallon compressor.

It's rated at 6.2 SCFM at 40 PSI and 5.3 SCFM at 90 PSI. Tell me how that is going to work with any HVLP other than a mini gun?

Put it another way. Imagine a distance runner in the last lap of a race. Just because he is breathing the maximum amount that he can, doesn't mean he is getting the volume of oxygen that he needs. So he is in an anaerobic state. Or a guy with asthma is breathing as much as he can but isn't getting the oxygen that he needs. Using an HVLP with an undersized compressor is like the above scenarios. May seem like it's working but it isn't functioning fully.
Just reminded me of my first compressor. 24gal craftsman. I was using a DA on it and it wasnt close to keeping up. The tool got so cold I had to use leather glove. The compressor I have now can run 2 DA and still build pressure
 
OP says his pressure is holding despite his setup doesn’t work on paper. I think it may be because he has choked off his gun using the valve on his Iwata gun. That would lower his air consumption and lead to his issues that Barry is attributing to low air. Just a theory….

Don
Even if it builds pressure it doesn't have enough volume. Volume is more important than pressure with an HVLP.
 
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