I have been looking into getting a gun for spraying the System Three WR-LPU for a final clearcoat, and painting the board with acrylic before laminating.
Do you guys have any recommendations on what guns you use? full size or will a touch up gun work?
So far searching the archives, I saw the several guys liked the Fuji HVLP turbine, spray system. I was considering this but also read somewhere that the air would come out too hot for the wr-lpu, and I would end up with it drying before getting to the board.
If I don’t go with the turbine system, I was looking into getting a Devilbiss Sri Pro gun, which is a touch up gun. Would that be ok to spray a surfboard with, or is that too small?
The guns are pretty expensive, but I can’t afford to buy cheap stuff:)
I’ve not used the Fuji turbine system, so I can’t answer the heated air question , but I do use an HVLP gun for certain items and can tell you that if you buy the DeVibliss gun make sure to check your compressor output spec’s beforehand. The conventional HVLP guns require ALOT of air (hence high volume low pressure). The DeVibliss gun requires 3.5 to 4.8 cfm (depending on the tip you use). a typical “craftsman” type 16 to 20 gal. compressor can’t handle that even if it is rated to do it (in use, once the tank drain downs & the motor kicks on, it can’t keep up with the gun & then the “material” won’t atomize properly. I’ve had to “jerryrig” a system using the two comprressors I own (2 lines into 1) to get my gun to spray properly.
I have about 8 systems, Fuji, CHausfield, 3M, cup guns HVLP’s etc …and a Harbor Freight Detail gun.
I keep going back to the HF detail gun, it’s cheap, efficient, and works fine. I use it mainly for my final gloss clear coat work, 2 pac LP stuff. The trick is in the details of how you spray. Even a good gun in the hands of a novice will create orange peel and craze…drips etc. Move too fast get over spray, move too slow get drips, sags, runs etc. A cheep gun with a little knowledge is no problem, most surfboard spray work is done flat so there should be a coverage issue.
Go with a cheap gun, they work fine, make sure like above you have enough air. But for most surfboards I can use my little pancake compressor, seems to work just fine.
Hey Resinhead, just curious: which HF touch-up gun are you referring to? I like their old-school siphon-feed touch-up gun a lot (with the top-mounted trigger). Technically, though, I can’t use them at work as they’re not compliant with current regulations. Here at the coating shop I manage, we’ve gone through probably 15 to 20 of the purple gravity-feed guns they sell. Some HVLP, some not. They can be decently-performing guns, but it’s always a gamble whether they’ll leak at the fluid tip or not. A lot of times I’ve lapped the needle to make it seat properly. They also come full of grease and must be cleaned before use.
We have one of those DeVilbiss Sri touch-up guns. Very nice gun. Great ergonomics and sprays like butter. Pricey, though. And I think normally comes with a tip that’s on the smallish side for what you’d want to do.
My favorite gun is now out of production. Devilbiss Finishline 3 HVLP. The best workhorse spray-gun I’ve ever used and I could get them for $100.00.
For shooting surfing boards you don’t need much. Like said before, it’s just as important to make sure you have enough air and that you’re using the proper reducers/retarders for the temps and the paint system you’re working with.
One suggestion: If you’re going to be shooting water-based stuff and solvent-based stuff out of the same gun, make sure you don’t get any intermixing of petroleum solvent residues in the acrylic. A lot of times it’ll instantly turn to jello. If I’m switching from an aqueous paint to a solvent-based paint or vice-versa, I flush the gun with a little 99% isopropyl alcohol.
I use the little purple troll size detail gun you are refering to. I keep it set up exactly the same, clean it with laquer thinner…nevwer touching anything. When it rots out, I get another one for 15.99 on sale. Like you said decent for shooting surfboards, but I’d never try to shoot a car with one.
Bear in mind, I’ve only shot a handfull of boards. Usually I’ve done one side at a time, horizontally. If you’re concerned about bonding at the overlap on the rail, I wouldn’t sweat it too much. If it takes you a few days to get to the second side, a light scuff with some 220 or even red scotch-brite should suffice. Actually, resinhead did an awesome thread on this very subject not too long ago.
As far as shooting the whole board at once, it’s doable if you have the right arrangement. I’ve hung boards vertically from a fixture inserted in the fin plugs to do this. It gets tricky, though, if the board isn’t fairly short.
I just got done shooting a board today, it’s warm today so the 2 pack goes off pretty quick. It’s not as fast as a gloss coat, but pretty fast. 2 pack to touch dry is about 15 mins, to handle is about 1.5 hrs. you can flip a board in about 2.5 hrs. You can wet sand in about 6-8 hrs, but best to lets sit overnight. Polishing need to sit at least 24 hrs…if you don’t it will burn and turn to rubber goo.
Also this post must have jinxed me, because the bottom turned out great, but the top the gun sputtered and spitted, dripped and sagged…Might be time for a new $15 gun…does anybody have a 20% harbor frieght coupon they dont want?