Air Hose for spray gun

serjik911

Promoted Users
So, i know its a dumb question. but still. why 1/4 hose is not enough and requires at least 3/8 for spraying? when i connect to 1/4 30 feet hose, i still have stable 30 psi at my gun. can someone, please, explain how that works and why not to use 1/4 hose.i understand that i just shouldn't using 1/4, but i still want to know and understand how does it work.
thank you
 
IF it works for you, why are you worried about what other people might say? Everything is dictated by the compressor. If it works it works, if you decide you want to use 2" pipe out of the compressor, you are basically making a bigger storage tank, but bigger tanks are also harder to fill when the compressor ends up running twice as much getting three times as hot.
If you pull the trigger and its at 30, you hold the trigger wide open and it stays at 30, morse code open and close and it stays where you want it, you are good. If it doesn't, you do not have the CFM requirement needed, so you adjust how you spray to how it works.
You might be getting good results now, decide to go 3/8 or 1/2 hose like has been suggested here and have it not work anymore.
 
Volume (CFM or SCFM) is not the same thing as pressure (PSI).

For example: a spray gun will state that for proper operation it needs 13 (CFM) at 30 (PSI). Any diameter hose can be set at 30 PSI but the smaller ID hose can only deliver a certain volume of air per minute.

Illustration:
Imagine you are using a 1/4" diameter water hose to fill a 55 gallon drum. The water pressure is 40 PSI but that little hose is going to take forever to fill that drum.
Now take a 3/4" diameter water hose and fill that drum. The water pressures is still 40 PSI but the volume of water it can accommodate is 3 times greater so it will fill the 55 gallon drum much quicker.

A 3/8" diameter hose with Hi-flow fittings will ensure that you are getting the proper volume of air so your spray gun operates efficiently.
 
The Prevost couplers are well worth the money. They last forever. The Milton V style couplers don't last at all before you are fighting to get them disconnected, especially when using tools with a lot of vibration.
 
will that work right?
 

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oh, another question: do you recommend these small airfillters at the gun inlet? will they reduce cfm as well?
 
Here's an example.
Flexzilla makes a great air hose as well.
https://www.amazon.com/Flexzilla-High-Flow-Coupler-Piece/dp/B01CK42BOG?th=1
not a fan of Flexzilla because they have very thin walled aluminum fittings on the end and even using the right wrench its going to strip getting the coupler on the first time. The hi flow couplers I have bought are blowing out o rings constantly and have to keep getting changed, its down to needing vise grips to hold onto the hose. Nice flexy hoses, just not a fan of the ends.

As far as the gotta have CFM, I get it, but if you increase the size of your air hose, you are going to require more CFM to get the pressure up. I am sure its not going from 1/4-1/2. but you gotta have the compressor that can do it and you might just hear the compressor running more. I dont know if he has a 2.5 hp pancake tank compressor or a 50 horse screw. If you do not have the CFM, you will not keep that 30PSI consistent at the gun. When you lose the CFM, that pressure is going to drop.
 
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hvlp guns should have a 1/2 in hose . 1/4 will not feed them . pressure has 0 to do with it . iwata is 18-24 lbs but needs the volume to work . my flexzilla hose in my booth is 5 years old still going strong .
 
i hate quick couplers . i bought a bunch then removed and threw them in the trash . all my stuff is flexzilla now .
 
I know Prevost has the True-Flate couplers, and I know the Milton M style plugs went into the standard Prevost couplers, but I'm not sure if the Milton V style plugs are compatible with the Prevost high flow couplers.
 
i love the flexzilla hoses. i have 2 that are atleast 10 years old now. its the only ones that last except the one i made out of aeroquip line lol. i do know i am not a fan of theose flaxzilla couplers though. as stated they are all aluminum. those woulnt hold up a week around here. i just switch mine to all steel couplers. i get about 2 years of daily use out of a steel end.
 
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