Trouble with HVLP Sprayer

I'm having some trouble with an Ingersol Rand spray gun. This is the spray gun you can get at your local aviation store. (in my case, Lowe's) I was heartened by the fact that one is supposed to get a much higher quality coating with it. Today I tried spraying AZKO primer with it. The results were terrible. The spray was blotchy and chunky. It was terrible.

Does anyone have any suggestions about what I might be doing wrong?

Danny

Danny, sorry to hear about your problem. I have the same exact gun and it works like a champion!

With regards to your question, I am not really sure. I can, however tell you some things I have learned about mine.

First of all, the trigger valve has a tendency to loosen up and come off. This is that little valve under the trigger that controls the air through the gun. I seem to recall it being a 10mm or so fitting. Make sure it is tight and check it frequently.

That COULD be all that is wrong. I dunno...

Also, I don't use much pressure at all. I shoot at about 7 pounds pressure. Not sure if that is right, but it works well for me.

The directions are pretty good and all I can say is try it again per the directions and holler if you have a problem.

If you do, give me some more info and we can go from there.

Hope this helps!

CJ

Here is two things you can try.

1.Turn your fluid knob in. It's the one on the back of the gun above your hand. As a starting point, turn it all the way in then two turns out.

2. Turn your air up. It's the little knob on the gun body below your hand. If your finish is chunky, as you describe, you don't have enough air to break up the paint into small bits in the spray pattern.

I hope this helps

Be sure to run the paint through a strainer before putting in the gun. You'd be amazed at the crap that's in there sometimes, and it'll make the gun spray very erratically. Also, that AKZO primer needs to be stirred real good before putting in the catalyst and after.

Steve Zicree

Another item to check is make sure you have the correct needle valve and orifice for the type of paint you are using and maybe you need to reduce the primer more for your gun.

Roberta

Danny
There was a previous set of posts about HVLP guns that you would probably find interesting. It was centered on the Harbor Freight HVLP guns, but they are all pretty much alike.
Here's a copy of some information I provided in an earlier post, but you can search on "HVLP" to get them all:


I purchased both sizes of the HVLP guns from Harbor Freight and have used both of them to prime and paint the interior of my RV8 using epoxy primer and PPG Concept paints. No problems with the plastic cups with either the paints or clean up thinnner.
HVLP is, to me, better than the normal high pressure spray guns, once you figure them out. You will use less paint since there is less over spray, but there are differences in how you use them.
Following are some lessons I learned in using HVLP:
-Make sure you have the pressure going in to the gun set high enough. These guns use 43 PSI going in. This allows the correct pressure at the nozzle, which is about 10 PSI. (You can experiment with different input pressures, but the pressure required for your gun should be stamped or printed on the handle and you can go from there.)
-There are three basic settings on the gun as follows:
-Trigger/needle...hold the trigger completely open (Squeezed in, like a gun) and adjust the needle so that you just begin to feel the trigger move.
-Adjust the fan knob (The knob by the cup inlet) to full open.
-Adjust the cheater valve (Material control) at the bottom of the handle to full open. (Note: If the material is not full open, the gun will "spit" paint and you'll get orange peel.)
The above would be the basic settings for the HVLP gun. If you need to make the fan smaller, you would need to turn down the material some as well to compensate.
Other tips would be to make sure you at least use a disposable filter at the inlet to keep water from the air hose out of the gun.
If you will be turning the gun upside down or tilted, put an old sock over the cup to catch drips from the air hole.
When actually painting, if you are used to a high pressure system, you will need to change technique a little bit. The following should help:
-Hold the gun a little closer to the surface being painted. Remember, with the lower pressure being used, the paint will not spray as far as under higher pressure.
-Move the gun along faster than you would, but not much, since you are closer to the surface. Also, the HVLP will put out more material than you may be used to.
The hardest part for me in painting is patience. Make sure all of your surfaces are properly prepared. Put on a light initial coat (Don't worry about coverage) and let it set up for at least 15 minutes or a little more. (During this time, I pour the unused paint back in the mixed batch and put some reducer in the paint gun. This keeps the paint in the gun from setting up and clogging things up while you wait for the current coat to dry. Put some reducer in the cup, spray some reducer through the gun, then disconnect the air and let the spray gun sit till you are ready to paint some more. A very small amount of reducer is all that is needed for this.) This will allow your subsequent coats to have something to stick to. My second coat is usually a covering coat and then a third (Heavier) cross coat to flow out and make a smooth surface. This has worked well for me, but don't forget to allow enough time between coats for the paint to set up or you will get runs.
Hope this helps. Good luck.

Painting

Like Roberta and others have mentioned, I would also be VERY sure to check your consistency (thinning) of the paint. HVLP, standard paint gun, Wagner Power Painter, airbrush....in any case/spray rig when spraying paints, the consistency of the paint must be right on the money. It is difficult to explain the exact mixture as it cannot be too thick, and it cannot be too thin. I know that is a vague answer, but try to play around with the mixing of the paint and the thinner (and/or catalyst). Too thick and you get the problems you described; too thin and the paint is very 'runny'. When running the mixed paint through a strainer, it should flow fairly easily into the paint cup. As a way to give you a basic idea, perhaps the consistency of say, orange juice (without the pulp of course).

Painting issues can be extremely frustrating since you may have other problems beyond the consistency of the paint. The settings on the gun (like the other folks mentioned) must also be dialed in. The good news is that once you finally get all the settings correct and the mixture/consistency dialed in, everything should be smooth sailing.

For us casual painters, painting can be very frustrating. Experience in recognizing problems and how to correct them can be a challenge in itself. Best thing to do is get practice using primers and start the finishing on smaller parts, that way if you really goof, you won't have so much to sand off or reshoot.

Roberta

thanks!

Thanks to everyone who responded. These have given me a lot of good places to start. I went ahead and sprayed with my old gun and things came out well. I'm going to get a test batch of paint going and fully experiment to work things out.

Danny

Hvlp

Danny: I have zip experience but my conversion gun came with a metal cup which has a hole in the bottom. It's to adjust viscosity of the material to a good value for the gun. Just adjust the paint etc until it flows out of the cup and empties it in a standard time - then the viscosity is right, at least for my gun. Bill