Thursday, November 25, 2021

Spraying Lacquer With An HVLP Spray Gun

Spraying Lacquer With An HVLP Spray Gun

Good afternoon, and hello again, this is the cheap Calgary painter here again. In this spraying lacquer with an hvlp spray gun blog post we have a combination of finishing techniques to share with you. Sometimes I use polyurethane brushed on, and other times I spray lacquer. The advantage to spraying lacquer is that it dries quickly, so that you can sand it, and apply coats within 30-minute breaks, as opposed to polyurethane sometimes you're waiting up to 24 hours in between coats. 

I've also had a lot of finicky issues with polyurethane as far as bubbles and things like that. That's usually from shaking the can instead of stirring it is what the pro painters have to save. Typically I don't have concerns with bubbles with lacquer, but the reason why this spraying lacquer with an HVLP spray gun is because I just got bit from an old technique that I forgot since the last time I sprayed. So I've been meaning to make blog post about this. 

My goal is to show you the setup that I have, basically how easy it is to spray lacquer if you understand a couple things, and I'll show you the trick that just bit me. I caught it because I could see it in the finish and now my gun is spraying good again, so let's jump over the equipment and get started with the basics of spraying lacquer with an HVLP spray gun. 

Alright so this is my general setup. This is an HVLP gun that I got off of E-bay. It's made in China. I don't know the exact brand, but there are a bunch of them out there, and it has its own air regulator here, which I run the gun at 40 psi. And I'll show you how you don't figure that out by static, it's actually by flow. And I'll show you that In a second. 

And the really important thing with these guns, is the size of your tip. So it's in millimeters, and if you look real closely, you may not be able to see that. Oh it's upside down. 1.8 millimeter tip. In my experience, the larger the tip you have, the better for spraying things like lacquer. The type of lacquer that I'm spraying I get from a local store here in town, and its ait's pre catalyzed lacquer. 

Usually this lacquer has a six-month shelf life. This one's a satin. The way that I mix this is with a ladle, and I have my own separate can right here, and you basically stir this stuff up really well. Don't shake the can like a newbie. You want it to look milky like that, and this is an oil-based one, not water-based one. And I use a metal ladle, and I do two cups of the lacquer, and one cup of the lacquer thinner. 

You mix it up real well and then put it in your gun and I'm going to show you basically how you adjust the pattern, and how you spray. If you're really serious about doing this, get some info that explains all the intricacies of the guns, which if you're gonna do it, you might as well do it right the first time. I'll give you my quick blog post version which is this knob here controls your pattern as far as how wide or how narrow it is. 

I usually run it at about 1/8 inch pattern. So this button here controls how much flow, like how much product is going to the gun. I leave this wide open, and my experience with pre catalyzed lacquer, it's better to have a bigger tip gun, and flow as much as you can through it, so you get a big heavy flood coat. I'll talk a little bit more about this. 

This is an air regulator, down there it was set from the factory, and I just leave it as it is. All right, so what bit me on this last spray, was these little holes on the side. I don't know how well that's gonna come up with the camera, but basically how this works is, that when you open the trigger, product comes out of here, and this air spray is what disperses it. 

Now it might be really hard to show you on this tabletop what it looks like, but basically it's a really fine orange-peel finish. So if you see an orange peel finish coming out of your gun that's usually an indicator that it's not being atomized correctly, which is what all those little chambers of air do. So I pulled the tip off, and I cleaned it, and then I did another test spray on one of these bench tops, and it went much better. 

Hopefully in the light you can see that where the light is reflecting off there, there is no orange-peel finish. Now there is a little teeny bit of dust on there, that's one of the disadvantages of not having a professional spray booth. I'm in my 2000 foot garage, this is my shot. You have to have the door open.

The fumes from spraying this pre catalyzed lacquer is really really flammable, and many people have had their water heater spark it and blow themselves up. So it's kind of a trade-off. Obviously if I wasn't pressed for time, I would just wait for the wind to stop, and then I blow my whole shop out, and usually it's pretty good but look at that finish. 

For a cheap Calgary Painter spraying in his garage, I mean that looks beautiful. Perfect, and flawless is what we shoot for on all lacquer jobs. And there are no streaks in it at all. As long as you have good overlapping pattern. So let's go over to actually mixing the product, and I'll show you a little test spray and hopefully we can spray a piece here. 

We're getting ready to do our mix here. So again, get a secondary container. What I do is two scoops of the lacquer followed by one scoop of the lacquer thinner. These are all kind of approximate mixes, it doesn't have to be dead-on for in my experience. Now you want to mix it up really good. Now is where it does matter. 

We buy these things from E-Bay or Cloverdale or Dulux paints. They come in a pack of about 50. Every time I reload the gun, I use a new one of these. So basically you put this on top, put this in, and now you're ready to go. So this is the compressor that I use. I actually really like this compressor a lot. 

It's a 29 gallon Harbor Freight, it's a belt-driven, it's not a diaphragm compressor, so it's not as loud and obnoxious as the other ones. I'm sure hear it kick on in a second. You can use this style. I wouldn't go any smaller than this, but here's the important thing. Let the compressor rest because if it gets water in it. That's gonna ruin your finish. 

So for those of you that don't know how an air compressor gets water in, it is the actual compressor unit when it gets hot it creates a moisture in it ,which gets in your line. So it has a drain down at the bottom of every compressor. I always blow that out before I start spraying. And then you can buy this one is not fancy, but you'll see if you see moisture up here you need to stop and let your compressor cool.

One other thing that I do is that I have a little nozzle that I hook up and I actually shoot it into the sun and you probably can't see that right now, but basically if there was moisture in the line I would see the vapor and the sunlight, and I would know that I need to let the compressor cool down before I continue.

This has only had three cycles since I've been starting so it's nice and cool and we can continue with the setup. Alright so what I said earlier is you want this as a flow pressure of 40 psi. So basically when I pull the trigger halfway, no products coming out. That's just air going through the gun. So right now you want that to stay 40 psi while you're getting ready. 

Now when you get ready to spray, if the nozzle is in the horizontal position, the pattern looks like this. It's up and down, so you can see when I spray I'm getting a nice wide pattern. I can show you here if I turn this gauge it's gonna close my pattern down. See that. That is not good for spraying high end high quality interior trim with lacquer products.

You want it to be nice and wide open. So I'm gonna open it up again. Let's go over here. I would say earlier I said it's an 8 inch pattern. I think it's about a 10 inch pattern. All right, very important to wear a respirator. Not just a simple facemask. You could get sick or die. Let's get this set up, and we'll spray a a door and some trim. 

All right, it's really important before each time that you spray, you wipe down with the tack cloth. You want to get all the existing dust off of it, and again between coats. I'll usually sand with a 320 soft sanding block. Not 220. 220 can actually put scratch lines in your piece, so do 320. And then right before you get ready, go ahead and give it a good wipe down. 

So just to clarify, when I'm doing the wood preparation, I sand 80 120 180 and 220, and then I get it all cleaned up, and I put the first coat of finish on. I let that one sit for about 45 minutes, then I do a 320 light sanding on it, and then after that if there's no dust nibs. You can go right to spraying coats every 20 minutes. 

You don't have to sand between every coat if it's smooth. This next part may seem silly, but trust me, do it, and that's basically walk around your piece as if you were spraying to make sure that your line reaches. That there's nothing in the way, that you have plenty of space. Because you don't want to be spraying, trip, or catch something, and then stop, and have that jitter of your pattern. 

You'll see it. So I'll do a quick mock of a spray. The thing you want to be looking for is my overlap. We said an 8 inch pattern, so I'm gonna spray the ends, and then come through on the sides, and you want to actually look at the sheen to where we have a 50% overlap. Again always wear a mask. The winds blowing a little bit which isn't ideal. 

But these are called build coats. It's not going to be my final coat. So if a little piece of dust was in there I could sand it out later. here's we'll do a mock first and then the real thing. So hopefully what you saw there is a big fat coat laid down. That's the only way to describe this. The product is really, really flowing out of there. Max product out, matching the correct airflow. 

And you just get an awesome finish on this. So as you can see, there's no bubbles! I'm gonna try to get some light streaks in there so you can see this looks absolutely fantastic. And look, I mean the winds blowing, and I'm in my driveway. My sawmills right there. This is anything short of being sterile or a spray booth, and you can still get really good results. 

So I always leave it overhanging like this, so I can touch it on these sides. So basically I'm going to pick this one up from the sides, put it over there, and then we'll take a look at it again. All right, so I'm showing a different angle now of another new door for lacquer spray. And the reason why I'm showing this, is you can see that my technique is anything but perfect. 

I try to keep the gun at the same angle, but sometimes that varies a little bit. My speed varies a little bit but I can still get a really good finish. And before when I was learning, I thought that it was because of my technique that I was getting such poor results, that the finish was really inconsistent and the reason why is getting bad results before as I was using the wrong gun. 

I was using a tip that was one point two millimeters, and I had the flow restricted down to where I wasn't flooding it, so again, I can't emphasize enough, the bigger the tip, the better and the maximum amount of flow on the needle. Meaning that you release tension on the spring by backing that cap out and now you're getting as much product going through that tip as possible. 

Well that's the advantage of lacquers. Remember I said we were doing build coats, so basically I sprayed this about 20 minutes ago, I'm gonna just react it real quick, and do another coat, and then this is gonna be done. So I take it out in the light, and I can see that all I mean, it just basically it looks great. There's no I can't see any streaks I can't see any sanding. 

So the main advantage of this is, that once you get a flow going, you can really do a lot of pieces in a short amount of time. So we'll do one more final coat on that, and it won't be done. All right I hope you enjoyed this down and dirty blog post on how to spray lacquer. Remember this blog post is an introduction to spraying lacquer with an HVLP spray gun. 

You want to get good at this, you're gonna have to practice. Practice makes perfect. No practice, and you can't really expect to get perfect results every time. As simple as I made it look and sound, I have had a lot of rough days spraying before I got comfortable doing it like this. And so I encourage people to take notes. 

Again the measurements are like approximate. Though it doesn't have to be absolutely dead-on in my opinion, but you want to take notes of how much you're diluting, what air pressure you're at, what your settings are, and that type of stuff you are using. So that when you go back you know where to make adjustments. 

I personally don't think you need really expensive equipment obviously this is a Harbor Freight air compressor, a couple hundred bucks. These guns are off eBay, they're Chinese ones. I haven't found a big difference in between the really high-end guns and the low-end guns for what I'm doing. Now if you want to go spray a car or do something else that's a whole other ballgame. 

I'm talking about DIY lacquer door and trim painting in a garage, so remember that when you set out with your expectations at the end of the day. There are a couple things you need to do to make sure your gun is ready for the next time you spray. So what I do is I disconnect it from the air source, I take what's in there, and I put it back in my transfer can. 

You can save product that's been diluted in a can for I don't know I'd do it for a couple weeks, and it seems to stay fine once you disconnect it. I put lacquer thinner right here back in this chamber and I clean it all out with a paper towel and then once the gun is disconnected from air and it has lacquer thinner I pull the trigger and into the garbage can it goes until the stream is flowing out freely. 

Basically indicating to me that all the lacquer is out of there, and now it's just the thinner coming out which is like water. I leave the lacquer thinner primed in the gun. I think that's better to just basically make sure that things don't build up and then you take this nose piece off at the end of the gun and you are set and ready for your next spray job. 

If you're having trouble spraying or your pattern looks wonky, this is the first place that I go. These jets in here if they get clogged up the air is not going to be able to project the product and atomized it correctly, and that's when you start to get those crappy orange peel type looking things that happen, which is why I realized damn it the last time I clean this I didn't take this tip off so if you're having trouble with your patterns.

Take the tip off, soak it clean, use a needle to get all this stuff out, and then go back through your setup if you're having trouble. In my experience one of the problems was that the tip is not big enough. Use the biggest tip that you can. In this case it's a 1.8. Have the product completely open. You want to get as much flooded on there as possible. 

Make sure that this pattern is set correctly. This is your V pattern. Keep it at about 8 to 10 inches you don't want it too focused or too wide. And then your air pressure too. You want to have enough air pressure to atomize and shoot the product but not too much to where it seems like it's going all over the place. 

I do not use backup. I use one gun for one product. So this one is strictly for lacquer. I also have another gun a 1.8 millimeter tip that I spray latex paint with, and that works awesome too. I think I use the same ratio two parts paint to one part water or maybe it's one to one for that, but don't mix water-based products with oil-based, or these you know these pre catalyzed lacquers. 

Alright I hope you like this introduction to spraying lacquer with an HVLP spray gun. Remember that this is just to get you started. You got to practice a lot. Do some research and read some books and remember this is these techniques that I showed you are for spraying lacquer trim. We spray the doors in a booth, or in this case, in my garage, and we spray the trim and cabinets on site.

If you're talking about doing really high-end pieces or you want to spray a car I don't think you should use the same setup that I'm doing. Go find someone that can teach you an introduction to that. And last but not least, just remember. You will likely get higher quality finished results and get the best looking finishes by calling in professional painters. The low cost professional Calgary Painters over in the north east at 1/2 Price Pro Calgary Painting can help you with all of your lacquer painting and lacquer spray painting.