Painting question - high flow quick disconnects?

Thanks a lot Jerry. That helps out a lot. Lots of great info.

 

Ryan...
Lets get this into the Tech Archives please.

 

Since my original post I went through all of my air hose fittings and quick-connects (my set-up is not enourmous - just going from a compressor to a cleaner/dryer, then from the cleaner/dryer to paint guns, but the small inline hardware can add up when you consider adaptors, regulator fittings, elbows, quick-connects, and more) and replaced the small i.d. pieces with new fittings that have at least a 5/16" i.d. I actually measured the ones that looked 'borderline' too small. Adaptors, elbows, barbs, quick-connects, all of them. I believe I should have plenty of air flow now for painting. I bought all of my stuff from Lowe's. I originally went to a Devilbiss distributor and found that 10 of their high-flow quick connect fittings cost around $150.00 total. That's too much for me since I'm not a pro or frequent painter. An 8 out of 10 paint job is fine for my job. Thanks again for your info.

Deluxe

 

x2...lord knows i need all the help i can get on this subject.

 

I also went to Lowe's and bought a few fittings to get started. I droped 45 bucks and don't have that many fittings.

Jerry, thanks for all the info.

 

Since I do not have a spray booth and paint in the middle of my shop here are a few tricks I have used for years to get a cleaner paint job. One is to ground the car with a chain or wire to the wetted down floor. When you spray paint the car gets a static charge and will attract dust and dirt to it. Grounding it helps prevent the static charge from building up. Before I spray paint on the car, I spray some paint into the air around the car with the exhaust fan running, I wait a few minutes and then tack off the car. You would be amazed at the amount of dirt and dust this brings down out ot the air. With the car grounded and the air in the shop cleaned I get a much more professional looking job.

 

Jerry, all this good tech is gonna be ignore by may because of the thread title, you might want to repackage this info in a new thread, "paint tips Q&A with camarokid" or something.

 

I'm not a computer wiz so if somebody knows how to move the info to the Tech Threads , please do , Jerry "CK"

 

Bump. Lot's of good info in this thread!

 

A moderator will have to move it. They will usually take out the stuff that is not pertinent.

 

I think I'm confused and have a question. If a restriction is required to adjust pressure from the source, what is the difference in having the restriction (regulator) on the compressor end of the hose as opposed to the gun end?

Excellent thread! Most of my experience in this was way before the day of HVLP, I'm learnin'.

My condolences to Jerry and family.

 

I'm no pro, but I do know this; when air is in motion in an air hose the air pressure and air flow are greater at the beginning of a length of air hose than they are at the end of a length of hose. These are just general terms. The longer the hose the greater drop in pressure at the end. So 40 psi at the compressor tank outlet may equal 30 psi at the end of an air hose. 23psi at the inlet of my hvlp gun passes through the body of the gun and is reduced to approximately 10 psi at the air cap/nozzle/tip. Air fittings/connections throughout the path of an air line may have a smaller internal diameter than the hoses themselves. Therefore those fittings will restrict (slow down) air flow.

Deluxe

 

Rick , the regulator does not restrict "VOLUME" of air going through it , just the amount of pressure as the gun trigger is activated . The actual airhose itself holds a certain "VOLUME" of air also depending on length and I.D. size . I cut my teeth in with a Binks Model 7 and lacquer and enamel was about it buddy so I'm with you . I had the re-think my whole way of shooting when the HVLP's came into the mix . I knew from the first one I used that the chemical transfer to the surface being painted was much more efficient because of the lack of overspray and it was really pouring the coals sort of speak with the fluids . The other painters around my area call me "WYATT EARP" because ain't skeeeered to lay some clear down . Your first coat of clear needs to be as slick as the last ! That's where using the correct size couplers and fittings will really come into play here with an HVLP gun . The spray pattern get's wider , the atomization is better , and modeling of metallics just seems to go away once you get some time under your belt . I've litterally had customers tell me point blank not to touch thier car with a piece of sand paper when I was about to cut and buff it . That kinda makes you feel good when they are that happy with your walk-away finish . Take some old fenders and hang them up and just start suirting !Anybody can lay it down slick on a flat surface , hang those parts up and learn to get the sides just as slick and then you're cookin boy ! I would rather wet sand a run or a drip and have a slick job than to work your ass off sanding orange peel on a whole car . Don't be scared to hammer that clear , just don't hammer your base . After working with painters at the PPG training facility in Houston over the years I have learned that about 90% of most painters put thier base on too heavy and they can't blend for crap ! If we can get this thread moved , I'll get into blending secrets later . Jerry

 

I decided yesterday to go with -Automotive T 3/8"- I believe they will provide plenty of flow. HD and Lowe's have them. The i.d. of these pieces is approximately 5/16"

Deluxe

 

Let me make it a bit simple to understand . Take 2 airtanks such as on a compressor and have them both full of air ready for use . Both have the same psi in them . 1 tank has a 2" ID Ball valve on it and the other has a 1 " . Now crack both valves open at the same time on each tank . The tank with the 2" valve does not have as much psi leaving that tank BUT the VOLUME of the air is leaving faster because of the larger hole . The tank with the 1" valve has more psi leaving but less VOLUME because of the smaller hole . Most people would think that since the air pressure leaving the 1" valved tank is greater that that tank will empty it's air first but it's just the opposite . Same with an HVLP gun , it needs and works efficiently with volume and lower pressure because of it's design . When you don't have the volume it needs , people think they can create more volume with feeding more psi into an HVLP . IT DON'T WORK ! This may have sounded a bit crude , but I hope some of the younger guys out there understand it a little better now and I hope it better answered your confusion Rick .

 

Good luck with the 5/16 Deluxe . You only need 1 coupler and 1 female fitting for the hose that you paint with and the rest of your shop can be whatever ? I can't understand why after putting so much money in our rides that the cost issue of a couplder and fitting is such a big deal it seems ? Of course I have been amazed for years that guys will spend tons of money on engines , interiors , sound systems , wheels and tires , yet when it comes to paint , the first thing that people look at , they want to get by as cheap as they can ?????? Not saying everybody does this , but more do than not .

 

Is this Jerry "CK" that used to paint in the Victoria area? If so, I can vouch for killer paint jobs this guy laid on some friends cars.

PM me where you are working now. I have a pickup project I would like to talk to you about. Matt

 

Same one Matt ! How have you been ? Appreciate the compliments . You have mail , Jerry

 

I am taking mine back to Lowe's. I stopped by a local hose mfg and they had built me 3 short hoses with a 3/8 ID. I just happened to take my fittings with me and when they handed the hose over I noticed that the fittings from Lowes had 1/4" pipe thread on them, so even with the larger couplings they were still restricted down. Better than the 1/4" I had been using but not what I wanted. I bought the true 3/8" ID fittings and couplings. They weren't cheap but I wanted to be done once and for all.

 

Now I'm proud of ya ROOTY ! LOL

 

high flow fittings and no regulator on the gun are myths, I want to know wat ppg training facilities teach this cause thats not what I learned, I spray from 3/8" lines with regular milton industrial fittings, I use an Iwata 1.4 tip and run a good 3m regulator on my gun, I spray at 15psi with trigger pulled and never buff a production job, you need to factor in that you lose air pressure from your wall regulator to your gun. I like the regulator on the gun because you get a more accurate reading and its quick and easy to change. the regulator doesnt cut down your cfm's enough to notice and the expensive fittings are a joke. I say take the money you save on fittings and invest in a good gun like a sata or iwata. I have used high flow fittings and taken the regulator off my gun and noticed absolutly no difference in final outcome

 

Houston Texas , one of the largest PPG training facilities in the nation ! And not just the PPG facilities teach this either , the gun reps that actually know thier asses from page 8 will tell you the same thing ! And just for the record , I can spray "PRODUCTION" quality paint drunk and with one eye taped shut with 2 1/2" masking tape ! I gave you a compliment on another post earlier but I think I'll go back now and re-think my post ? I'm now guessing that you are a youngster that knows it all just because you have suirted a few cars and got some pat's on your back by the owners and the Boss that you work for . I listen to the judges at car shows about my paint and body to get my feedback and that ain't a myth ! "Your pappy was a pistol "and now I see what came out of the end of his barrel ! This is what makes forums fun though I guess , differences in opinions . My last Harley was on Speed Channel because of the paint and I used my Devilbiss fittings on that paint job and guess what ? NEVER BUFFED !

 

Very informative thread

Thanks Jerry

 

Great. Right now I'm in the middle of building a new shop and I just know I'm going to either forget this shit or lose track of this thread by the time I get to the next paint project.

 

That's why I am kind hearted enough to give you my personal cell phone number to refresh your memory on any questions that I may have answered that you think are worthy of knowing ! 361-649-6135 my real name is Jerry Dodson but I go by "CK" ...CamaroKid ....on the internet . I love people until they give me a reason not to , and I love teaching those that actually listen to what I have to offer from the years of my experience in the paint booths . I have already realized a long time ago that I am poor , I will probably die poor , so why in the world would I keep knowledge that may help others that may need the knowledge that I have learned over the years . I have been to quite a few funerals in my 45 years on this Earth and I have never seen a luggage rack on a casket yet so all you people out there that may read this that are greedy and stingy , try giving a little more to those in need because you damn sure ain't taking shit with you !

 

I know this is an old thread, but I found it a couple of months ago when setting up for painting and it really helped out. I had painted many years ago when a Binks JGA502 and Single Stage Enamels were the way to paint. Old technology in both supplies and tools. Fast forward to HVLP and paints that can kill you dead quick. I had purchased the compressor and the Iwata guns to get me going. Once I read this thread I figured I had to give Jerry (Camarokid) a call. Either he was really full of it or knew his stuff. After talking and eMailing him, I set up a dedicated air line as he described with the Devilbiss high flow couplings and no reg on the gun. The atomization on the paint is incredible! I have another line with the Milton High Flow V couplers and I tested it out to see if there was a difference. There was, so I figured Jerry knew something about painting and so I would keep bugging him until the project was done. The project was a 300M that a friend owned and his wife backed into the door. I told my friend I could get a junkyard door and paint it to match. Let the fun begin.
The door was rougher than I imagined and I had to start at the very beginning. Many eMails on the process and Jerry told me the right way to do it. As I told him, I’m too old to waste time trying to figure it out – so I asked his advice and he basically walked me through the entire project. I had read horror stories of people seemingly doing everything correct and winding up with a redo because they played junior chemist and mixed the wrong stuff, didn’t wait long enough between steps, used several paint systems on the same project and ran into compatibility issues, getting stripes or mottling in the paint, etc… This is why I took Jerry’s advice and followed his instructions to the letter. It worked out very well.
I will let the pictures do the talking and you can judge for yourself. I have not painted anything in 20 years and this was basically a novice attempt after being coached by a professional over the internet! And you thought internet dating was rough
The final word is that Jerry did not have to help me or could have stopped at anytime or not thought through what he was telling me just to get me off his back. My opinion is that he knows what he’s doing, can teach it, and had a great deal of patience for putting up with my newbie questions. Is he God’s gift to the Paint world? I don’t know. But what I do know is that he spent a great deal of time helping an individual he never met and stuck it out even when he probably thought I was hopeless.

Thanks Jerry
This 300M door is for you…..

Dave
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Looks very nice!
Interesting read on this thread, some facts and some myths. I thought that being pretty versed on basic airflow and painting I bight be able to throw in a few tidbits. The flow ( mass flow ) of air through your system from compressor to gun is constant, pressure is not. So while your pressure is dropping from compressor to gun over the length of the hose, flow is not. That being said if my Acme brand supergreen demon HVLP gun needs 8psi at 13cfm at the aircap, I can get there with a 1/4" hose or a 4" hose, one will just need a higher initial pressure at the compressor, and more energy at the compressor to overcome the increased restriction. Nothing magic here, just basic fluid dynamics. However there will be a difference in the temperature of the air at the gun, provided they started the same at the compressor, the smaller line being colder due to the pressure drop over the system and related expansion of the air. So if you are compressor limited, use as big of a line as you want to haul around, and remember that the only pressure that matters, is the one measured at the aircap.

 

I know this is a really old thread but the tips included were a great help. Thank you guys who contributed, especially CamaroKid.

 

Very good read I'll keep this one close for rereads never hurts to do a little studying.I'd like to see CK do a new thread . Roger

 

Jerry, I just found this thread, read all of it, loved your input, you are very knowledgeable and a great person for sharing with us. Thank you and GOD bless you and yours....Ray...