I have been using a touch up spray gun like the one Foam E-Z sells…it has a nice fine spray, it works great on smaller area’s but not so good for doing a whole board. so I bought a Gravity Feed HVLP spray gun from Harbor Freight. I don’t know what I am doing wrong but I can not get this gun to spray very good. I tried everything, fluid control knob, air flow , lower or higher air pressure nothing seems to help. With to thick of paint it splaters to fine it runs. there doesn’t seem to be a in between. the only way I got it spray half way good was to thin the paint alot but it takes 10 or more coat of paint to get a ok looking finish. I went through over a quart of paint and it still looks thin. I can still see the foam. the touch up gun covered in just two three coats with less paint… what am I doing wrong? I am taking that HVLP back to Harbour Freight…any suggestion as to a really good air gun.
Eddie, I’ve never used a Harbor Freight spray gun, but I would suspect that the quality is not so good. A lot of their products come from China where labor is cheap, but quality control can be erratic. Good spray guns are pretty finely tuned because of the small holes that the air and paint need to pass through. I would recommend an auto body type gun. They can be had for under $100.00, or well over that amount if you can afford it. Also, with HVLP guns, you are laying down a higher paint-to-air ratio, and on the larger guns sometimes the paint goes down pretty heavy if you’re not careful (been there). With a good spray gun, though, you will be able to make adjustments for the spray without the headaches you’ve been having. After 25 years as a woodworker, buying many tools over the years, my philosophy on buying tools is: Cheap tools are too expensive. You pay more by having to buy them more often, and more importantly, you pay with headaches and poor results. Save up for the good stuff. It only stings once, then you have a long time to enjoy a quality tool. Doug
Hey Eddie, I use a HVLP all the time, (FUJI) it works really good. But as the name implies High Volume Low Presure, these units put down a lot of paint down with out much over spray, that’s the beauty, quick painting not much mess. Usually the turbine unit needs to be at least a twin if not triple turbine unit. The more turbine the more $$. If you didn’t get 3 different needles for different viscousity of paint, fine, medium, and Heavy, you got ripped off. Usually the mediun needle with a heavy tip works will for Tempura type paints, thin the paint down to where it drips of a screw driver at about one drip per second. Usually this means to thin the paint about 10% but not more than 30%. The whole point is to get the paint to atomize properly. Too little cut, the paint spits out in chunks. Too much cut, the paint runs and soak in like water. I think any paint gun has a learning curve built into it, but some units are better than others. Work with the gun and you’ll find the proper mix. If not you can always spray Insecticide with it! -Jay
Doug & Jay thanks… The reason I bought this HVPL gun (Central Pneumatic) was that it has a stainless steel needle for use with water based paints. but no other needles. I looked around and this gun was pretty much the same Chinese made gun others were selling with a differant name for way more. you guys say it puts down lots paint. I don’t know where it’s going cause after five coats it still looks very thin with the foam showing but my cup is empty… my 30 day cash refund is up so I will have to get store credit…anyone know of a spray gun that HB sells that would be a better choice?
thats the exact gun (central pneumatic from harbor freight)i used to airbrush a few years back. no problems whatsoever, did like 30 boards with it. i think the one you had is defective.
Hi I got a free spray gun with my compressor. The quality is questionable. On the first board I sprayed I thought I had stuffed it up the spray job and the splatter was so bad. But on the second board I put water in the spray gun first sprayed my hand and adjusted it until I could feel no more splatter then I used a thicker paint about the consistency of a thin gravy. And the results were much better. I used fewer passes with the gun a it was a smoother finnish. Good luck
Howzit Coastal Eddie, Could be the needle gasket is not sealing properly, it’s very important that it seals otherwise the sprayer will suck air and the gun won’t work worth a darn. When I’m not using my sprayers I always back off the nut that tightens this gasket so not to bugger it. As far as your paint not covering you may have thinned the paint just alittle to much and it becomes like a tint instead of an opaque and no matter how many coats you apply it will still look the same. I’m a self taught airbrusher and it took me almost 2 years to get my paint mixtures and spray settings down so everything would work the way I wanted them to. Find an area in your shop where you can do test sprays before you apply to thr blank. Aloha, Kokua
I use Tempra paints thinned with acrylic addmix (used to make grout waterproof). The tempras were purchased from Surfboard Factory and are cheap. I have two airbrushes (both cheap Badger units) and thin with 1 part acrylic to 2 or 3 parts paint for the airbrushes (around 25 psi). My large area sprayers are both Harbor freight - one is a cheap auto touch-up and the other a cheap full size (not HVLP). These can tolerate stiffer paint (at 60 psi delivery) and I mix 1 part acrylic to 3 parts paint. For hand brush work I mix a bit stiffer - as the acrylic/tempra dries relatively flat and without lumps and I like the color density to show brush strokes. The acrylic makes the strokes lay down smooth on the foam and seems to reduce the resistance to adhesion that causes the paint to develop pinholes as it dries. Initially each of the spray units was difficult to get to work as desired. I now have a very colorful wall in my shop from all of the test shots. Vary air pressure from the compressor, paint delivery volume needle, and paint thicknesses until it looks right. Keep scraps from blanks to test adhesion, color quality, and transparency. If you try different paints you should also laminate the test piece and vigorously work the resin to ensure that the paint doesnt run on a finished board. Alltogether I prefer the color quality and various grades of transparency avilable from artist qualiity acrylic (Liquatex) I found the cost outrageous and they dry too fast for use in spray units. Remember, finished art is the result of what you imagined tempered by the limitations of your media and application. Good Luck!
Jason…yeah I took it back to Harbor Freight…they said that they have never had a problem with that gun yet…they gave my cash back…On Harbor Frieghts web site they have that same gun Item 43430-8GVA on sale for $39.99 was 64.99. I am tempted to get another one.
Hi been reading posts regarding spray gun I work alot with compressed air and tools.It may pay to check your filter regulator to make sure you can get fine pressure adjustment and that the filter regulator is working properly which supplies air to the spray gun.Hope it helps Frederick