Cfm’s and filters

Dave C 5

Dave C 5

Member
My current setup has me going through a water trap and 2 divilbiss QC3 dessicant filters - water problem. They are rated at 16 CFm . I don’t know what that means compared to air flow . My regulator after the filters say 120psi and I don’t “think” it’s causing a problem but I’m not an expert. I bout a refrigerated dryer I will be installing. Ditch the QC3’s ? I like the added security but is the cfm’s hurting me ? And I’m gonna buy a new regulator- cfm’s rating recommendations? I will say that I can’t get around the car without the compressor kicking on - 80 gallon duel stage - custom built with HUGE motor runs about 800 rpm - guy who built it use to build them for factories so I’m pretty sure it’s good- don’t know why I get so much water though- anyway- is the cfm’s rating hurting me ?
 
Oh - and I have about70 feet of 1.5 inch galvanized pipe from my compressor to my filters - I’m guessing the air dryer can be mounted after the compressor? Or better at the end of my pipe run ? The air compressor actually has an inner cooler- coiled copper out of the head, wrapped around the belt drive then into the tank
 
Dave what make and model of your dryer are you getting. Where are your QC3 filters located in your air system?
 
Bought that harbor freight dryer and my QC3 filters are at the end of the 70 ft pipe run - right after my water trap which is after my motor guard - it seems I get great airflow but the 16cfm rating on the QC3 filters worry me - especially when I see everything else rated. At 50cfm- is it possible to get 100psi but not. Enough cfm’s ?
 
The QC3 will be fine for spaying. Don't think your gun (s) will need that kind of CFM. Let me know what you think of the harbor freight dryer.
 
You need a drop with a drain valve at the end of the 70 foot run before the Motorguard. It will catch a lot of moisture.

Don
 
Actually have 3 drops on that run - don’t know why the water is so bad - good to hear my qc3’s are good - hopefully this dryer works cause I use two filters per car at $50 each
 
That sounds like a crazy amount of water you are getting. Have you drained your tank? How hot is your tank when you work it?

With a true after cooler between the head and inlet of the tank it should cool down the air to room temperature and the condensed water will drop to the bottom of the tank. That is where an electric auto drain with a timer comes in real handy. You should be able to touch the inlet pipe going into the tank without getting 3rd degree burns, the pipe coming out of the head into the after cooler will be around 350deg, enough to sizzle spit.

The mixed up CFM ratings on your filters mean nothing it won't hurt anything.

Is it possible to get 100psi and not enough cfm's? Yes, think of 100psi through a mixing straw and 100psi through 1in pipe far more air will come out of the 1in pipe. Your cfm's will only be as great as the smallest hole.

Your water problem is the biggest issue I see you have, no doubt.

Any pics of the compressor?

Watch the specs on the HF and make sure you have it set up properly.

Where is your compressor set to start and stop pressure wise When your working it?
 
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It’s filthy right now - been stripping a car - pressure is set at 140. I do get ALOT of water - way more than I hear you all talk about - drain my tank a couple times in a 4 hr period - easily get probably 3-4 cups
 

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Where do you live?

Media blasting a car will use a lot of air and generate a lot of moisture. Painting should not. I would not be passing media blasting air through a dessicant filter....
 
Heat makes water. What RPM's are you spinning that pump. Look at motor RPM, measure the OD of each pulley and search a pulley calculator on line and plug in the numbers. My little Quincy 325 running 475 rpms averages 1/4 cup a day but it depends on humidity and time of year because it's in the unheated portion of my barn. So this time of year it's makes hardly any water.
 
I live in central Illinois- the man who built the compressor rebuilt the pump- as you can see it’s all industrial stuff- was a factory compressor mechanic for 40 years - he told me he had it set to run between 800-900 rpms - takes a while to fill up ! 80 gallon tank . Really not sure why so much water - I thought I would fix the problem with this compressor wen I got rid I’m my ingersol rand piece of crap ! It did the same thing - weird thing is : I can drain a lot of water out of the tank but hardly ever get water out of the drop legs
 
And I don’t media blast - I don’t really know much about compressors . I’m not sure this is the greatest one either - seems to kick on a lot when sanding and cut off wheels - the cut off wheel bogs down to quickly for my taste- I tried to get a name of the pump and motor but everything is painted over - I’ll try again when I get home this evening
 
For my one drop I have my pipe go down 4ft then a U with faucet and return up 4 ft then continue on horizontally to the filter. I wonder if just a drop on a T to the main line is as effective?
 
From the picture you can see I have 2 drop straight down and I use the “faucet “ style for my drop down that my filters and air come off of
 
Dave C 5 said:
I live in central Illinois- the man who built the compressor rebuilt the pump- as you can see it’s all industrial stuff- was a factory compressor mechanic for 40 years - he told me he had it set to run between 800-900 rpms - takes a while to fill up ! 80 gallon tank . Really not sure why so much water - I thought I would fix the problem with this compressor wen I got rid I’m my ingersol rand piece of crap ! It did the same thing - weird thing is : I can drain a lot of water out of the tank but hardly ever get water out of the drop legs
Click to expand...

if your only getting water out of the tank you have no issues and the after cooler is doing it's job, if you are getting water out of your lines then you have an issue
 
Getting water through the lines - that’s why my filters don’t last - it’s just my drop legs don’t seem to be catching much- just ordered an automatic drain valve - maybe that’s what I need - have to admit that I forget to drain the tank frequently. the aftercooler from the head must do a good job cause the tank gets a lot of water but it’s making it’s way through 70 feet of pipe and trashing my filters - I will be installing my dryer in the next week I hope and hoping that takes care of it in conjunction with the automatic drain valve
 
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