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I am painting a guitar with nitrocellulose lacquer from StewMac. I bought a color concentrate from a company called Mixol. It was highly recommended to me by a friend. I pigment is violet/purple, but it is not metallic violet/purple. Can anyone recommend a product to me that is specifically designed to make nitrocellulose lacquer have a metallic effect? I don't mean, so metallic to the point of it being glitter. But metallic like an automotive paint is sometimes metallic or like how a Gold Top LesPaul is metallic.

I appreciate your help!

There are two kinds of metallic finishes... One has the metal flakes mixed in the finish. Candy colors have a silver or gold metallic finish applied first, and then a transparent tinted color coat on top. On a goldtop - there is no tint in the top coat.

For a custom mix, you can purchase metal powder (usually aluminum) to put in your color coat. A little goes a long way. Complete suspension of the flake in the lacquer requires thorough mixing before and even agitation of the cup during spraying. Also, spraying a metallic finish sometimes requires careful attention to your spray nozzle to get the right look, and also an adjustment to spraying technique when laying down coats to keep it from looking stripey.

I usually hold my gun a few inches farther away from the guitar when spraying metallics, and have more overlap in passes. It's tricky, and a little practice beforehand is a good idea for best results.

_________________
"Act your age, not your shoe size" - Prince

There are many ways to do this.... some use a single coat with the metallic in it and others use a metallic base coat (usually silver or gold) with a tint over it. Metallic is different from flake. Flake is coarser and more sparkly while actual metallic is more subtle.

The easiest way to a metallic nitro finish is to by a auto re-finish basecoat like PPG DCU already mixed in the exact shade and metallic you want For a single stage you can omit the hardener and use it like a conventional air-dry acrylic.

I use Mixol too but that is not a good rout to a metallic finish, you need something that lest more light through, Mixol is very opaque. As Chris mentioned you can add powdered metal like aluminum or bronze and that is a very old school way and look. Most modern "metallics" are enhanced with or based entirely of pearls. This stuff is fabulous, equal in all respects to house of kolor at a fraction the price
https://www.paintwithpearl.com/shop/candy-pearl-paint-colors/metallic-paint-candy-pearl-paint-colors-candy-pearl-paint-colors/purple-candy-pearl/

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Brian

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

https://www.howardguitarsdelaware.com/

Thanks for the product recommendation! something like that is exactly what I was looking for. One thing I did not mention, only because it would have made my post long and complicated for no reason, was that I am using the Mixol's "Silver" metallic effect to spray the whole guitar silver. I am binding the edges in white, and want to paint the edge of the guitar purple. I did not, however, want to have the silver main color, have that metallic look, but then the purple edge just be an opaque purple. I want the purple to have the same metallic quality.

So, my first thought was to spray the whole guitar with the Mixol silver at a strong 10% ratio of pigment to Nitro, and then come back with a very light purple tint, and candy over some light purple passes on the edges. But... I also want the purple to be strong enough of a purple to really pop. So, since i am in totally uncharted waters for my own experience level, I have started to worry that by the time I build up enough purple tint to really pop, the metallic silver underneath will be so tinted over that you can't see the metallic effect.

So the purple purl powder that you linked to above seems to be the best of both worlds. I can still do the guitar in total Mixol silver, but then mix up a light purple with this pearl powder in purple, and "candy" spray the edges purple, but with the pearl effect from the powder.

Or would you recommend just going with a full on Purple pearl powder mix for the edges, and forget about the whole "candy" idea, since this powder is pearl/metallic enough as it is?

If you want an even look, spray a silver base and use a purple tint to shade the burst as any other. Mixing different metallics will have a bolder look with purple appearing more on top.

I have never used a Mixol metallic so I have no idea what to expect from it. But the type and strength of the metallic base will determine overall effect. For the purple you can use Transtint, Solar-lux or some of the candy concentrates from the PWP site I linked to before. Also note that when using metallic effect pearls or polyester flakes that background color becomes important in final look. A black background coat makes the metallic brighter and a white base looks more subdued.

If you had a reference picture of what you were going for I could maybe help narrow down the procedure and things needed.

_________________
Brian

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

https://www.howardguitarsdelaware.com/

Just out of curiosity.... How much experience do you have, Mr. Perkins?

_________________
"Act your age, not your shoe size" - Prince

Well... I have a great deal of experience as a woodworker. Meaning, I have finished countless pieces of furniture, and even make my own varnishes and finishes myself.

But from a, spraying guitars, pov... I have very little. I have only used aerosol paint cans in the past, and while I've gotten good results, it was never an "elegant" process. I'd end up starting over, or building up clear coats so that I could wet sand flat. Etc etc.

This will be my first [ use a spray gun — tint your own lacquer ] project.

That being said, I am thoroughly prepared to spray 20-30 plywood mock-bodies to practice. I am not under any time constraints; I just lack experience. I am also not rich, so materials might get a little expensive for me to spray 20-30 practice runs, but... whatever.

My other problem is that I bought the StewMac HVLP spray gun, which cost $30, and I just have a little 6-gallon air compressor for tacking in brads and penny nails. The specs on my Bostitch 6 gallon compressor are just below the min. spec for the cheap StewMac gun. I just know that I do NOT want to invest in equipment. I earn almost zero dollars at this. I cannot invest $2k in a nice gun and compressor.

Here is a very rough "sketch" that I made in Illustrator of the guitar from the side: https://goo.gl/RaC5wX. It has a "German carve" cove around the top. It is a vector graphic, so you can't see any "metallic" effect.

However, for actual color examples...
If you look here: https://goo.gl/LDKVEw, that is the "Metallic Silver" look I desperately hope to achieve.
If you look here: https://goo.gl/CdAanu, that is the "Purple Metallic" look I really want to have along the edge.

Am I kidding myself?

That shade of purple over a silver base will be tricky... may be better off not using a shader and doing a duo metallic. I was thinking something more like this....


So I would run a silver background and then tint some of the same silver metallic with red & blue or purple mixol, maybe all three plus some white.... May need to go plus 1/4 or 1/2 on the silver metallic to keep the look even between the non loaded metallic and the colored one. Color load here is going to be heavy and you want it strong enough to go down as thin as possible. Thick builds with lots of color craze easily. You may even be over the 15% mixol states (which is stability limit for a top coat) but in a base coat we can go 20% or a bit more as long as you run a lock-down clear over this immediately.

The metallic coats have to go down perfectly! They cannot be sanded or leveled in anyway or the effect is ruined. Working this all out ahead on test panels is a good idea and something I do on custom jobs where precise color or look is required. Tip size and proper reduction are critical to get a good even metallic. Since you are new to spray guns I have some reading for you that will help you out.

https://howardguitars.blogspot.com/2015/06/spray-gun-setup-technique-by-brian.html
https://howardguitars.blogspot.com/2015/05/spray-finish-problem-solving-chart_18.html

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Brian

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

https://www.howardguitarsdelaware.com/

Woah!!! Thanks man! I really appreciate the help! I am going to go read the articles you posted. In the meantime, I really think that you've hit the nail on the head. I think I should spray the whole guitar in the silver (sides includes), then mask off the top and back just leaving the edge exposed, and then literally just add some of the purple mixol to the same silver I'd been spraying and spray the edges. I'll have to test it, of course, but I do not necessarily want, like a deep opaque Prince "Crown Royal Bag" purple. I want it to be a silver guitar with a purplish "candy-like" edge. I'm probably over thinking it, and should just get out there and do some trial and error.

One quick question... When Mixol says "10%"... I can't find on their website if they mean, by volume, or by weight?

I only have one little 20 ml bottle of the silver and one 20 ml of the violet. So if it's by volume, that's... 20 ml x 10 = 200ml. That's just over 3/4 of a cup of total lacquer. I feel like I could probably waste that much lacquer, just trying to get the hang of spraying. Do I need to go ahead and order another (larger) bottle of this EXPENSIVE stuff!!! (ha ha ha) or am I misreading the whole "10%" thing?

We are talking volume of colorant to RTS mix. So yes 25ml mixol to 250 ml of RTS lacquer. This can vary some depending on the solids content of your lacquer and amount of reduction.

For reference I use 75-100 ml of shader to do the average burst. I seldom use just a single color but 150 drops of mixol is plenty to do an entire guitar body in most solid colors.... lighter colors need more coats so use more colorant.

_________________
Brian

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

https://www.howardguitarsdelaware.com/

Michael, you are getting some really good professional advice from one of the finest instrument finishers in the business. I want to give you a different perspective. I've built two dozen guitars to date and finished all but one myself, mostly with nitro. I build and finish in a garage using some pretty basic equipment - a small home compressor, inexpensive gun, makeshift paint booth, respirator. I have done both clear, fades and sunbursts and some translucent colors - never a solid color, metal flake or metallic finish. My guitars are adequate, getting better, but a long ways from what Brian does. My goal is something Paul Reed Smith would be proud of, right now you can probably see a better finish on a basic PacRim import.

When people ask me about guitar building I tell them that IMHO finishing is one of the hardest parts for the home builder. We simply do not have the materials, methods or experiences that a pro has. And lets face it, the finish you are dreaming about is about as difficult as you can get. I think that is what Chris was getting at with his question and your answer tells me a lot.

Before you consider mixing any of your expensive metallic and dyes get to the point where you can lay down coat after perfect coat after perfect coat. Learn your gun and compressor so well that you can field clean it in your sleep and understand exactly why you are setting the pressure or nozzle or mixture the way you doing it - try different combinations until you have it dialed.

Then shoot your metallic and your color and your clear and make sure you have that completely under control. Then, and only then, hang up the body that you have worked so hard on and nervously spray your first coat. Then come back here and show us the results.

Thank you guys, really, very much! I will follow all of your advice Freeman.

I do wish that I had already spray finished 20-25 guitars in just a basic solid color before I go jumping head first into the deep end with metallics and tinting my own lacquer etc. But the person I am building this guitar for asked for these specific colors. I'm never one to shy away from a huge challenge, so I said, "sure!" And I WILL get it down. I might blow through $300 in materials, and end up ponying up some cash for a better gun. But I'll get it!

Right now, I have the following equipment:

This StewMac (brandless) Spray Gun https://goo.gl/fxv2wk — Has a 0.8mm nozzle, and costs $38
This Bostitch 6-gallon 150 psi oil-free air compressor https://goo.gl/6qs7kz
1 quart of StewMac's Nitrocellulose Guitar Lacquer https://goo.gl/2GugAR
1 (20g) bottle of Mixol ME2 Silver Metallic-Effect Pigment Concentrate https://goo.gl/Kh1Pmg
1 (20g) bottle of Mixol 11 Violet Pigment Concentrate https://goo.gl/niJ3vn
A 3M full face respirator with VOC cartridges
Neoprene gloves
several practice pieces of wood

What I do NOT have, but am concerned that I will need.
A pressure gauge/regulator that attaches to the gun. The compressor has a gauge, naturally, but I do not have a second one.
A strong enough air compressor
A good enough gun
Talent/Experience/Skill

You can do a good job with what you have at hand. I have done with a similar set up in the past.

What you need that is not on the list is a clean, safe work space. Venting flammable fumes safely is a real concern with spray guns and lacquer. Cleanliness when spraying metallics cannot be stressed enough. One piece of dirt can ruin the entire job and make you start over. You also should have a filter/dryer of some type on your air feed too.

You may also need some reducer and maybe retarder as well. That small of a tip may force you to reduce a bit more than typical to get flow through the gun & atomization. I use a 1.3 for most clears.

_________________
Brian

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

https://www.howardguitarsdelaware.com/

Yeah, I read your blog posts that you gave me. I thought too that my tip might be too small, considering it is almost half the size that you use. StewMac doesn’t sell tips, so I’d have to either find one that fits this nonane gun (I’m borrowing the gun, as I haven’t invested in my own yet.) or I can wait until I can afford a higher quality $150-$200 gun w/ a larger tip. About the clean space, I have a large workshop that has a big full sized window. My plan was to buy a box fan for that window, and really seal off all around it. Put a furnace filter in front of it, and build some kind of spray booth using either 2x4s or pvc pipe, and plastic sheeting from Home Depot.
My shop is a saw dust nightmare though. I have a 2hp Delta dust collector for my table saw, planner etc. band I have an air filtration unit that that hangs from the ceiling. But still... dust settles on anything that i don’t touch everyday. So, i don’t know how to avoid it.
I have a laundry room that is connected to my house by a standard door that would probably be a better location. Also has a window. But it is so cold these days... well... cold for Chatkeston, SC anyways. It’s below 70 for sure. I’ve heard that the fumes of nitro are way too powerful to spray the guitar and then bring it inside my house to stay warm. (Right?)
I can def buy some lacquer retardant, but I don’t know what the other stuff you suggested is. A dryer?

Mr. Perkins - You'll just have to dive in. There's a learning curve, for sure - your technique and your experience will improve. It's one thing to say how to do it, or watch a vid - actually doing it is the best teacher. You'll learn about viscosity, humidity, tinting, using retarder and mixing finishes by trial and error. Lacquer is pretty forgiving, if that's what you spray.

As a kid, I learned to spray using rattle cans on model cars.... It was ugly at first, but soon I won some classes with my finishes. When I started doing guitar repairs and refinishing, I was using a humble rig that got the job done. My first pro job was a Gibson 330 in pearl white. I sprayed it in a horse barn with dirt floors. Came out very nice, only a few troubles along the way, and I found a way to deal with them and make it sweet.

Later, I had the full big rig - Sharpe touch-up guns, huge Campbell-Hausfeld compressor, paint shaker, and a Binks spray booth in a dedicated building with explosion-proof lighting. I've painted hundreds of guitars and other instruments. Then, in the 90's - I got small again, and went back to using my humble Miller 2000 rig I bought at KMart for a mere $20 back in the 70's. Single action, several nozzles and cups, with a lo-buck air filter.

Here it is: https://imgur.com/IhIz5K5

And yet, I've done these with that rattling compressor and flimsy airbrush:
https://imgur.com/DPfGR57
https://imgur.com/Iqc6kKF
https://imgur.com/yvlLZMq

Got paid good money for doing them, too. Doesn't take impressive gear, just some knowledge and experience. Go for it, and good luck!

_________________
"Act your age, not your shoe size" - Prince

Another comment from the peanut gallery. If you laundry room is attached to the house or shares HVAC, or if there is any source of ignition (pilot light on a water heater, heating elements, anything that can spark - then don't shoot nitro there. Lacquer is toxic and highly explosive. I shoot in my detached garage and my wife complains for a week about the smell in her car. Brian and Chris can talk more about temperatures - I shoot down to maybe 60 F with acceptable results.

I used to put my mixed lacquer in a shallow bath warmed by crockpot on low. Warming the mix really helps it flow out smooth.

_________________
"Act your age, not your shoe size" - Prince

B. Howard, I very much appreciate your advice... and everyone else's advice as well. You guys are incredibly generous and kind. If you're ever near Charleston SC, beers on me!

I am going to get started practicing with the set up I have, but I will also be saving a few dollars for some better equipment. I am having trouble, however, finding resources on HVLP equipment that is not very slanted towards a particular brand or company. Also, most everything seems to be geared toward automotive painting. It is really difficult to find information specifically on spraying nitrocellulose guitar lacquer.

Can you tell me what you meant when you said, "should have a filter/dryer of some type on your air feed too."? I imagine you are saying that compressed air probably precipitates out moisture due to the pressure change, and since water is the enemy of solvent-based lacquers, I need something that can dry the air.

My one problem is... I have this tiny Bostitch air compressor and a no name spray gun. In the near future, I'd like to buy a MUCH better gun, and probably a new compressor. If I buy a dryer/filter for my current setup, will it work with all other setups that I might buy down the line, or do these companies try to hook you in to their "ecosystem" and I'd need to decide now what brand of gun or compressor I'll buy later?

Michael, this is probably about the minimum setup you can use to spray lacquer. Please note that the gun and nozzle are probably not correct for shooting metallic, I know they are wrong for flake. Anyway, the compressor is 2 or 3 hp, the tank is 8 gallon. At the end you see the pressure gauge and regulator, I set the line pressure there (a little more than what I want at the gun). There is also a small filter and water trap at the point the yellow hose is connected. You are correct that compressing air forces water to condense. The water trap has a little valve on the bottom, push that and the water is expelled.

I paid 50 bucks for the compressor at a yard sale, it had the pressure gauge and regulator, I added the filter and good quality hose. Note that I only have a 20 amp single phase circuit to my garage, that is marginal for this motor (if I'm trying to run any other equipment like my small space heater it will trip the breaker.



It is nice to have the little compressor in my garage - its handy for airing up tires on the cars or running a few small air tools. However its pretty marginal.

This is the cheap little gravity feed gun that I am currently using. I bought it at the local auto parts store for 25 or 30 dollars, added the pressure gauge and regulator for 10 or 15 more. I do not know the nozzle size, it has worked fine for shooting solvent (nitro) and water based lacquers, as well as alcohol based stains.



The picture was taken when I was finishing a guitar in red lacquer, the significant thing there is the pink respirator.

Just for chuckles, here is the guitar that was being finished. The finish consists of some red stain that was applied to the maple to highlight the grain. That was sanded back and sealed with what is called vinyl modified lacquer - it keeps the color from bleeding from the wood to the finish. It then has 6 or 8 coats of nitrocellulose lacquer with a few drops of red dye added, then 6 or 8 coats of clear nitro.



As I said in an earlier post, I consider myself a good amateur finisher - this guitar was the 18th that I've built and finished. I'm satisfied with it but there are definitely flaws. The multiple coats and translucent red are tricky but not nearly as tricky as the metallic that you are considering.

Take your time, practice a lot, listen to everything Brian has to say, then practice some more. Report back, I'm looking forward to seeing your guitar.

I am going to get started practicing next week. I will start with just water spraying several sheets of scrap cardboard. After I have hosed all my cardboard, and/or feel a little confidence, I will switch to spraying water on to scraps of birch plywood. Cardboard is so absorbent, I'd like to see how easy it is to spray too heavy and make the water run down something like plywood. I don't know if this is a great idea because water and lacquer have such different drying times and probably viscosity. I know it is good to practice a lot before trying something. However, getting in several hours of practice with water, only to find out that thinned, tinted, reduced, and retardant added lacquer behaves completely different.

Oh well, gotta start somewhere.

Can anyone please make a recommendation for a good air dryer/water trap/filter that I can add to my air line. That seems to be a common theme, that I need one to spray lacquer. I found one for like $350, but I am looking for a highly effective, yet... more modestly priced solution.

Dude!!! @Freeman... that ES 335's finish looks KILLER!!!! RIght on man!

Two minor comments. Many inexpensive guns have ferrous parts that will rust. When you are thru with your water dump a little denatured alcohol in the gun and shot it into a rag. Water is soluble in DA and DA won't rust the gun.

Also, you will learn a fair amount about your gun, what adjustments do and how to start and stop your spray, but you really need to practice with something of the same viscosity and flow characteristics as lacquer. You won't learn how heavy/wet/far to spray until you actually spray lacquer. Don't waste your expensive color or metallic, but plan so sacrifice a quart or so of the same stuff you'll be using.

You can buy gallons of cheap thinner just for cleaning your gun from your local paint supplier.

_________________
"Act your age, not your shoe size" - Prince

What is Lacquer "Reducer?"

Lacquer thinner is a solvent that "dilutes" lacquer's suspended dissolved solids.
Lacquer retarder is a chemical mixture that causes lacquer to dry slower, which helps with leveling, adhesion, and with driving off water to prevent blushing.

But I hear the word "reducer" tossed around some. Is that just a synonym for thinner, or something else entirely?

Along with Melvyn Hiscock's book, let me suggest Dan Erlewine's book on finishing

https://www.amazon.com/Make-Your-Own-El ... 0953104907

https://www.stewmac.com/How-To/Books/Gu ... -Step.html

ps - I use the terms synonymously but it is possible that a branded can of "reducer" has something in it designed to work with that manufacturers product. "Reducer" is almost always more expensive than "thinner". I buy hardware store thinner in gallon cans and use it for all my cleanup. "Retarder" is something entirely different - it is added to slow drying time and reduce haze or bluing. Again, if you read Erlewine's book (and Brian's blogs) you will know everything you need.