HVLP Full flow? After all of this I find all my gun psi gauges are only 1/8 I.D.

[Overspray]

Lively discussion.....

Well I have come back to let all know what I came up with in design.

Yeah some of my gauges were cheapos and others were older good ones but all restrictive.

Also IMO, the overall air industry is a cluster %#@! of mismatched and uncoordinated manufacturing with relatively restrictive proprietary in-house design characteristics which often do not lend to interchangeability to other mfg's fittings, etc.. But it is what it is, so I designed my own system as most of you have done as well I suppose.

In re-designing my old overall HVLP air supply setup to my guns, I wanted to design an air gun supply hose system which would be more user friendly, ego designed, flexible while also delivering maximum air flow as opposed to the standard setup I have been using for years. Many of the application, flow and consistency painting problems which are talked about on this site, I believe stem from inadequate consistent air flow. HVLP requires 5/16 min. I.D. flow throughout your entire system with only 1/4 inch I.D. at the gun handle allowed.

So, my new design would require cutting hose to make short whip hoses. I purchased DeVilbiss high flow fittings, quick change fttings Q.D.'s etc from Len here at his store. The quick change fittings require a 11/16 O.D. hose. However very common just a few years ago, affordable, very flexible 200 psi 11/16 O.D. hose to be cut as needed when needed is as I was to find out, unobtainable today for the most part unless you buy a long length of DeVilbiss hose. U. S. Made Goodyear and the China lovers now manufacture air hose that keeps the 3/8 I.D. but sports a 5/8 inch O.D.. So if you need to buy short length cut segment hose and go to your local jobbers, air compressor store, big box store, hydraulic store etc, they will carry this new 5/8 O.D. hose. (Unless they have old stock still on hand) I am talking about the 200 psi very flexible air line hose of yore. They all seem to have this yellow stiff 400 lb stuff at 11/16 O.D. but it is unsuitable as a painting hose. Now, this is fine unless you are going to put these quick fittings on the ends which require 11/16 O.D. hoses to complete a correct and non leaking install. Also, when using DeVilbiss high flow fittings one must stay consistent by using any and all of their fittings, nips, adaptors, reducers etc. starting from your gun handle's 1/4 O.D. NPS all the way to the air supply Q.D. and stem that goes into it. DeVilbiss has machined their fittings to match only their counter part fittings you may choose or elect to use while plumbing up your gun and lines. Now there is nothing wrong with this but I wanted as part of my design, more freedom of movement for the hose so I also included some full swivel barb ends which are full flow obtained from CoilHouse Pneumatics in my design. Long story short: I ended up cutting some of my old true 11/16 long length hoses off to make my new designed whips since I could not purchase short length true 11/16 hose.

I decided that a manifold regulator at the point of dispersion just after my dedicated painting filter with 1/2 inch input/output is best for me. No 1/2 inch input, 3/8 out put filters or regulators. Only 1/2 inch in and out equipment is used. At the 1/2 inch I.D. exit air port I have installed a high flow non restictive true 1/2 I.D. brass and stainless ball shut-off valve which connects to a 1/2 inch ( 1/2 inch I.D.) brass quick disconnect (Q.D.)

To this I then have my dedicated paint line air hose. A 1/2 inch I.D. hose ( 30 - feet ) that has at one end a 1/2 inch stem ( 3/8 I.D.) and a 1/2 inch (3/8 I.D.) "Brass" Quick Disconnect (Q.D.) at the other end. I plug the stem end into the air supply. That leaves the other end to connect to my painting whip ends I have made. These whip hoses incorporate the Devilbiss high flow parts purchased here on this site from Len, but also includes high flow / full barb swivel ends obtained from Coilhouse Pneumatics which is a full swivel Mega Flow barbed fitting.

My Whips:

I connect the handle end of the gun to a brass Coilhouse 3/8 FPT full swivel fitting and a plumbed female brass reducer which has a 1/4 inch I.D. which matches my gun handles 1/4 inch I.D. This is connected to a 3-foot segment of cut off 3/8 I.D. x 11/16 O.D. hose ( my old stock ) which in turn connects again to a Coilhouse 3/8 full swivel connect which has a DeVilbiss male full flow stem. This in turn is connects to a belt mounted DeVilbiss full flow analog gun gauge with a DeVilbiss full flow Q.D. on each end of the gauge. I have built a belt mount clip w/belt for this gauge setup so when I want to disconnect the gun I can do so at any time. From the belt mount setup, I again have a 3-foot whip hose with the same CoilHose full swivel connects at each end that then in turn attaches to my main 30-foot 1/2 I.D. dedicated paint air hose. The result is absolutely no binding, tugging or need to wrap the hose over my shoulder. There is no junk hanging off the end of my gun. No restriction of lateral motion or getting into tight places as my swivel ends combined with my flexible hoses allows total movement. When I need to clean the gun, I disconnect at my belt from my supply and walk into my clean room and reconnect to a air supply when and if needed to have the ability to blow air through the gun while cleaning. I store the gun with the whip hose attached. One and the same gauge for all my guns as a dedicated mounted unit. I also use the 3M PPS when needed. My setup is like a pressure pot system but completely mobile. Though I have incorporated more Q.D.'s than using a minimalists approach, I have compensated for this by using a larger supply line and full flow fitting. I have no restriction less than 5/16 and the gauge is my most limiting aspect but is at least a full flow DeVilbiss gauge.

For my primer gun setup, I use another whip hose design identical to my painting whip hose design but have eliminated the belt mounted gun gauge setup entirely but still have a swivel at this juncture. I control my gun at the wall mounted regulator and use test sprays against a lighted bulb source background. What I want to see is a complete and full spray pattern from tip to fan, not thin full at one end and thin at the other. To adjust air/flow rates I do so at the regulator and also listen to how my gun sounds and equate that with the visual for an overall proper output and have no problems with dry pack, orange peel, running or spats giving me sleek smooth full coats of high build primer or epoxy without having to over reduce or constantly dick with adjustments.

Hope this helps anyone out there. With HVLP use and ensure consistent air flow and rate. Cool dry abundant slow moving air is a must.