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Will do, I'm going to get a pressure guage for my gun, and do some serious cleaning this weekend and see what happens...

To be clear, you should not need to break down and clean the entire gun between each coat. Only the aircap and the outside of the tip (as long as your gun doesn't leak and drip...). Any material sealed in the gun should be fine for the time stated by the coating manufacturer and usually only a problem with "hot" 2 part mixes.

Have you tried adding a bit of distilled water as reducer? This would be a slow reducer and give just about the most flow time of anything without getting into glyccols. A few drops per quart can make a big difference with some products.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Can I Brian? The label on the lacquer says explicitly to not use water and only reduce with "Brite-Tone" reducer.

FWIW, I got curious about Brite-Tone and tried it out to see how it compares with my go-to EM6000. I don't claim to be an expert on spraying and might not even be worthy to clean Brian's gun. I did succeed in finishing one instrument with the stuff but it took quite a bit of material and plenty of level sanding to get a smooth finish that could go through the steps through machine buffing. In fairness, the finish turned out to be very clear with no hint of blue and seems sufficiently hard. My wife took a shine to the instrument so it has remained with us for about nine months and so far has been stable in all respects. I did try using the correct reducer in the prescribed amount in an effort to get it to flow out well using various adjustments to an Iwata conversion HVLP gun. I never found the magic key to make it lay on anywhere near as well as EM6000, but maybe that's just me. After a reasonable attempt, EM6000 remained more attractive. It sprays through my gun without drama, sells for half the price of Brite-Tone, and there's no shipping cost because my local paint store carries it. End of experiment.

Since I don't know any better I err on the side of too much. I've been mostly shooting nitro lately but either way I completely disassemble the gun, pull the little filter out of the cup, take the nozzle and needle out, wash everything in DA (for water based) or lacquer thinner (for nitro). Put it back together, shoot some DA and hang it up with DA in the gun. If its going to be a couple of days I drain it and let it dry out. It often takes me longer to clean up that it did to shoot a coat but since I've been doing this I have had absolutely no issues. Brian says it isn't necessary but certainly can't hurt/

I'll make two more comments about your pictures. First, it really doesn't look like your pores are filled. Second, it really doesn't look like its level sanded before you start spraying. With nitro I have learned to spray a coat of vinyl modified sealer as the first coat. With water born (KTM-9) I frequently spray a couple of coats of very thin KTM (1:1) as the first coats - the idea is to really get it to flow into the pores and maybe even be absorbed by the wood itself.

I did use pore filler before anything else, but the pores in this wood (black limba) are huge and I kind of like the look of an open pore finish (is this the correct term) so I didn't go crazy on making sure every pore was filled. My intention was that a couple thin coats of clear coat would fill those pores a little more as you suggested although I didn't reduce as much as you do.

And I did sand it level, with 240 grit paper. It was pretty dead smooth other than the open pores.

The finish basically came out of the gun and onto the guitar body exactly as it dried. It flowed a tiny bit in places where it went on a bit wetter but not much.

They don't make any money selling distilled water..... All coatings labels have something to the effect that you must use there proprietary solvents. Because that is what there lab tested it with and it makes them more money. In the end if it is a water based or water clean up then distilled water will work as a reducer and usually a retarder as well. Much like acetone can be used to break the surface tension down on any solvent based coating.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Okay, so its about 16 degrees celsius here, I meticulously cleaned my spray gun this morning, thinned some of my lacquer with about 5% reducer and proceeded to do some test sprays.

So my gun says 30 PSI max inlet. I'm assuming this is the maximum PSI that should be entering the gun?



Here's a picture of my compressor specs



My compressor is reading 30 PSI



As does the guage at my gun.



This is what happens when I pull the trigger back all the way and give it a quick spurt.



Here's when I do a 12 inch pass over about 6 slow seconds...



Here's the same thing when I up the PSI to 40, it atomizes a bit better...



Here is is at 60 PSI...



I even ended up cranking it up as high as it would go. The atomization seemed better at higher PSI, but it was almost like it would explode out of the gun and then peter out.

Any thoughts?

I recently sprayed kitchen cabinets with Minwax water based poly and had no problems. I've used the gun to spray nitro, shellac, WB dye and WB poly. I'm not super meticulous about cleaning the gun and after 5 years I've had no issues.

Seeing your spray pics I'm thinking either there's something interfering with the delivery of air or finish or the product is bad. When you cleaned the gun, did you use spray gun files to clean out the air holes?

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Julie Moriarty
http://JulimorCreations.com

I soaked the cap in lacquer thinner, then used a plain guitar string to gently move anything out of the holes that didn't come out with compressed air and a tooth brush. The holes were really clean afterwards.

You might give the fellow at highline guitars a shout for recommended gun settings.
I shoot nitro: my gun manual says shoot at 35psi at the gun, but I get good results at 15psi.
I assume you tried dialing back the pressure at the gun already.

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wah
Wah-wah-wah-wah
Wah

Assuming the gun is clean you should have gotten something closer to a usable spray pattern with what you've tried.
Sounds to me that the finish is still too thick. How about taking a sample and keep thinning until it sprays properly. This
may not be a solution but it'll let you know if you will be able to spray the material with your setup. Or not. A simple viscosity
drip cup would be handy to measure the viscosity. Any cured WB material in the tip orifice won't dissolve with most solvents,
has to be mechanically removed. To test, something that's 1.3mm should slide through. I think you earlier said the tip was 1.3mm.
Good luck.

You may be right, after taking these pictures I went to clean up and had little lacquer left in my cup, just for fun I added about as much water and tried that out, it came out of the gun pretty messy but the droplets all flowed into each other and when it dried it was pretty flat. I'll try again tomorrow with more reducer and see if that solves it.

All those holes have a very specific size that should not be altered in any way. That's why they make files of the same size. A guitar string should only be used if it is the exact size of the hole. Also, you should get into the habit of spraying whatever cleaning solvent you are using through the gun after use, rather than just a soaking.

I haven't read anything here about checking the air cap size against manufacture recommendations. Your thinning experiment caused me to wonder if the air cap you are using is too small for the finish you are using. If all else fails, you may want to switch finishes.

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Julie Moriarty
http://JulimorCreations.com

Are you using the same air hose that you use for everything else? If you are, it might have oil and moisture and other contaminants in it. Get a hose strictly for the sprayer, and add a moisture trap before the pressure dial at the gun, and one after the dial at the compressor. I got much better results by doing this with my old Wagner conversion gun.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

It was just a thin plain guitar string smaller than the diameter of the air hole. I just used it to push the softened crusties out.

When cleaning yesterday I did spray solvent through at the end that seemed to do a good job.

I'll occasionally use the compressor to brad nail a project together, but it doesn't really get used often. I do have a moisture trap at the gun. But that's a good thought, if further reduction doesn't help I may try that out.

as Jules points out, there are specific items made for cleaning out spray guns...little tiny wire bristled cleaning devices of differing sizes are available. when dealing with lacquers I typically spray a fair amount of thinner through the system into a garbage can with a liner (using the real cheap thinners that are intended to only be used as clean up)...typically leaving the gun parts soaking should only be done between consecutive spray sessions and the gun should be thoroughly cleaned when it's going to be sitting around for longer intervals of time. if using a pressure pot with a dedicated fluid hose, that hose should of course have a lot of cheap thinner run through it and after a period of time said hose should be replaced just to make sure (honestly, this is the retentive side of me that worries about fluid hoses and how they might react to cheap solvents being run through them...as an example one batch of this cheap stuff went unused for over a year and when I did use it something wacky had gone on with it and it ate through nitrile gloves in a second and gave me a chemical burn...lesson learned, don't buy from that supplier ever again!). point being, hoses of all types are intended for use and should be cared for

when being involved in spraying I have an air hose only used for such activities and when not in use is rolled up and connected together via the quick couplers to keep anything from getting into said hose.

water....... distilled water...... said it a while ago.

Also you talk a lot about adjusting air pressure but i never see you mention fluid adjustment. Looking at the pics of what you sprayed I would open up the fluid needle some and keep the pressure at the lower side. The 30 psi max inlet pressure is while operating. Notice in my article I am feeding my gun 80psi static as measured at the gun (my wall regulator was most likely set at 90) but when flowing is about 28 psi......

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Conor, there is a thread at MIMF about Brite-tone finish, it sounds like people who are using it are getting good results. The thread isn't that old, many of the participants are still active at MIMF, you might want to PM them and ask exactly how they are thinning and shooting the product.

http://www.mimf.com/phpbb/viewtopic.php?f=13&t=3711

My first thought when I saw the pictures was to open the fluid needle until you get a really wet runny coat, then close it down a bit. Brian seems to confirm this. Also, in my very limited experience, when I get water born finish on something and it dries it is very hard to get off (my kitchen sink for instance). If you have hardened finish on the needle or the nozzle it still could be your problem. I don't know if lacquer thinner will dissolve it. And again, I don't know if it is correct or not but I've had pretty good luck cutting waterborn lacquer a lot more than 10 percent, maybe 2 or 3 to 1 (lacquer to alcohol).

Yup, it was your suggestion that gave me the idea.



I had my fluid needle open close to all the way.



So when I pull the trigger halfway and let air flow this it should read 30 PSI? As things are when when I pull the trigger the guage at the gun drops all the way down to 0 PSI.

Whoops thus the results you are getting.

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http://www.Harvestmoonguitars.com

I'll check out that thread Freeman, thanks. I have had success with this product before, both spraying it and even brushing it on a little bit. So I'm sure my problem is my own inexperience. I feel like I made some progress yesterday slowing down and being more methodical in my practicing rather than trying to rush into getting a guitar finished.

Summary: Gun is spitting large drops of finish due to insufficient air flow at the gun.
Solution?: Get more air flowing. You might have a bottleneck in your compressed air delivery/filtration system.

Any resolution?