This post has been a while coming....so here goes.
It has bugged me for a lifetime to have a spray gun in my hands. Dont ask me why its the one thing i have always wanted but avoided.
I avoided it primarily had to do with what i percieved to be the need for a huge compressor capable of a healthy number of CFMs of air.
Then a total lack of any prior knowledge and like the darn techie stuff i come to have a love hate relationship with, i did not want to be getting burnt in experiementing with various finishes and guns.
When one reads the reviews in this area on just about any suppliers site its a real mixed bag. Automotive guys are the big users is my guess and hence we have a mix of pro and hobby and auto and wood guys providing reviews which leaves you more confused than anything else.
Another thing, clean up. I hate painting in the house with a passion, even pva so clean up when one has used oil paints always put me off. Same thing for spray guns. I thought each time i use it i would have loads of little parts all over the show and tons of solvent......but its not true i found out.
Then you get guys like Dave H who seem to have been born with one of these devices attached to their hand and been fed an encyclopedia of information on finishes.
So i took the plunge recently when a harbor freight promo ad arrived in my in box and thought what the heck at $15 for a spray gun how can i go wrong and not try it out. The spec said 4.7 CFM at 45 PSI and i figured my PC pancake nailer compressor should do this somewhat. SO what if i have to wait every now and then, so what if i burnt the sucker out they relatively cheap. But i should be so lucky as to get enough time on it to do that, then i would happily replace and have justification for a bigger one.
So a dear friend did me the honors after i recieved my gun and together we drove around procured some lacquer from LV and got some of the correct thinners. I was actually very dissapointed in this case with the guy serving at LV because we asked for lacquer thinners and got this handed too us and if you look on their site having just purchased this lacquer which can be brushed or sprayed ( note the back door escape if things dont work out) the lacquer supplied is definitely not suitable.
Thank goodness my buddy was suspicious and we actually returned it before leaving the store.
Home depot obliged with the correct thinners but it was an education to note there are two types of what is called thinners. SO if you a newbie like me take note to get the correct one. This is thinners but NOT for lacquer and spraying.
Ok so next issue you need to know is which gun. Well if you in Canada you can get this gun at Princess Auto along with all the attachements you need. But mine came from Harbor Freight for half the price. this is the one i purchased after consultation with a friend here that actually has the same one and knew it would work for my needs.
NOTE: I get to produce very little out of my shop right now. Couple of years that will change kids out the house then. But even when i do, its all small stuff. So my needs are just to finish hobby stuff.
What i really would like is a HVLP Earlex unit which woodcraft has on special for $319 right now but i cannot justify it at present it would just be another dust collector to me. So YMMV.
But if you doing small stuff for sale like bottle stoppers and trivets etc, this could be a perfect quick way to get a good finish.
So i really could do with doing a proper tutorial here and putting it in a pdf and when time permits i may do it because i think for newbies this is an excellent way to go.
Get a couple of mason jars.
Step 2 get hold of a small ladle if you can, something like a gravy boat ladle. I actuall happen to have a couple of stainless little cups which served the purpose but you end up having your finger in the lacquer.
Take 2 measures of lacquer and one measure of lacquer thinners.
Mix in mason jar. Now you set.
Make sure you sanded your project and then blow off or wipe off very well the dust from the project.
(this stuff is amazing because the test we did was on a scrap project gone wrong where the wood had only been planed and was mahogany which is fiberous etc as a surface and it covered it all)
Step 4 set the pressure regulator on your pancake to 45PSI we actually used even a touch lower. (more about the compressor bit later).
Get a large piece of cardboard or something large you can spray on to set the gun up. There are instructions in the manual and i had it easy i had a guiding hand in fact my buddy did the adjusting but showed me how and what i was looking for while spraying test sprays on the sheet of cardboard. You want this sheet to be something that is gonna show the wetting pattern so think of this before you get going.
Ok fill the small gun cup to about 75% full. Put the lid on an be aware. There is something to understand about this gun.
It works on a siphon method. Meaning the air travelling out the nozzle creates a suction that sucks the fluid up the tube and atomizes it.
For that to work there is a little hole in the lid of the spray gun that needs to be kept clean and clear so air can enter.
Then note the three prong lever to tighten the lid onto the cup once you have it clicked into the C hooks on the gun can easily exert enough tension so as to bend the C hooks open. You dont need to tighten it this tight. You only need to snug it up so the seal on the lid keeps the lacquer mix from running out and down the side. Would be different if it were a pressure type spray gun.
Pray some lacquer on the board and adjust the airflow and liquid flow settings to get a nice pattern.
There is some logic here that is worth knowing.
There are two ears on the gun nozzle. when they are orientated in horizontal plane then the spray pattern is going to be a vertical oval and when orientated vertically the spray pattern is going to be an oval horizontal.
Set the ears by loosening the threaded cap that holds the nozzle on and rotating them into the horizontal mode. ie vertical oval spray pattern.
WHY? If you use a horizontal pattern then when you pass from left to right with the spray gun the pattern overlaps and can result in you putting down too much lacquer in one pass. Of course if you gonna spray up and down on a unit then rotate the nozzle the other way.
Ok so by now you have the spray gun set you got a nice even pattern of moisture and the oval is coming out vertical.
Wind up the NN by spraying outdoors.. Only kidding.
Ok now set the piece you want to spray up and begin with a spray pass starting with the gun trigger open and spraying at a height around 6- 8 inches off the object and get the gun going say 6 or more inches before its spraying on the object. Then take a nice even speed pass across the object you spraying. You can then come back and overlap the next layer and repeat till you coated your object on that side with one coat. Rotate the object and do the same till you have a coat all round.
Note you may need to refill gun before going to far depends on how much you used to get set up and how much you used on your first object. I would strongly suggest you use some scrap wood before you get going on a project just to the feel.
Now let this coat dry, it dries very quickly in fact amazingly so.
Now take 320 sandpaper on a block or preferably some 320 sponge sander and just wipe one stroke across the unit you spraying with the sanding sponge. Only one wipe.
The lacquer will look like white powder as you do this. Then take a nice clean rag and wipe it clean. Or even blow it clean.
Now you can go to finishing another coat and even one more if needed depending on the finish you desired.
Note: I purchased a satin lacquer there are three options . So the grain would show nice but not look glossy. Second, you can coat till the grain is completely covered if you like this or you can coat till some of its still visible. Its your choice. I like the look of gloss sometimes like say on a plane knob or tote but i like the look of satin grain on a flatwork object.
Let the coats dry for at least 2 hours before you shoot again in between layers.
Then you done. You can go to town doing other things after this but this was a good finish and more than adequate for a newbie on hobby projects.