# Orange peel - thin the material or use a larger tip?



## Quickstep (Apr 10, 2012)

I'm trying out a new spray gun. My first "shot" at using it, I got a pretty decent amount of orange peel when spraying Behlen Stringed Instrument Lacquer. The can says to spray full strength, but I know that can be subjective. Would you try a bigger tip, or thin the lacquer? Also, I've read that a little acetone can help lacquer level. Anybody ever heard of that?


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## epicfail48 (Mar 27, 2014)

I don't spray lawyer much so I won't be much help, but I have to say that thinning with acetone sounds like a horrible idea. As fast as it flashes off, I'd wager the acetone would make the orange peel worse, let alone the safety risk of having a cloud of aerosolized acetone hanging around


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## woodnthings (Jan 24, 2009)

*spraying "lacquer" ..... not lawyer*

Lacquer should spray like a dream IF the gun settings are correct AND the mixture is thinned properly. Use only lacquer thinner. :yes:

After a while you learn to read the mixture for the correct thickness or consistency. It should pour easily, not flow, but drool off the end of a stick readily. Automatic transmission fluid comes to mind. Somewhere between that and 30 wt. oil.

Then there's the gun ...which one? HVLP? I use a Harbor Fright $15.00 special for automotive panel repairs and some wood projects. Line pressure at 60 lbs, from a 50 ft hose, reduced to 40 lbs at the gun with a gauge and pressure control.
Fan control is the upper knob. Too small a pattern will cause immediate runs. A 6" to 8": wide pattern works well for me.
The paint volume is the lower control. You just have to find the correct setting... screw it all the way in, back out 2 to 2/12 turn seems to work. Practice on a cardboard box BOTH vertically and horizontally. Have a bright enough light or daylight so you can see the flow pattern's refection as you work down lapping over the previous path a bit. It should shine back when you are doing it right... no dull spots.

Anyone else got anything more...?


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## Quickstep (Apr 10, 2012)

I feel like I've got the adjustments set and practice on cardboard looks good, but when I spray on my wood practice piece I get pretty serious orange peel. I stepped up to the next tip size and the orange peel is as bad or worse than with the smaller tip. I guess I'll try thinning next.


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## epicfail48 (Mar 27, 2014)

Mother ****, autocorrect gets me on that one every time. Feel free to mix your lawyers with acetone, but I'd keep it away from your lacquer


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## RandyReed (Jul 30, 2014)

Quickstep said:


> I feel like I've got the adjustments set and practice on cardboard looks good, but when I spray on my wood practice piece I get pretty serious orange peel. I stepped up to the next tip size and the orange peel is as bad or worse than with the smaller tip. I guess I'll try thinning next.


Things to think about when you get orange peel:
1. Does the material being sprayed need to be thinned? As a rule of thumb, most materials need to be thinned.
2. How wide of a fan are you spraying and how far away are you from the surface? Usually 4-5” wide from 6-8” inches away works best.
3. Are you overlapping correctly? You should aim to overlap 1/3 – 1/2 with each pass.

You can use acetone to thin the lacquer, but it will cause the lacquer to dry faster, and depending on how much you thin it, it will also cause the gloss to go higher. Even lacquer thinner will evaporate quickly, and when its hot, thats the last thing you need to get rid of orange peel.

Do yourself a favor and buy some butyl acetate.......it will help most all lacquers and sealers flow out better, it will not jeopardize the gloss in any way, and the cure time will be the same as straight out of the can. Butyl Acetate is the baseline for all solvents in evaporation time.

Start by reducing it around 10%, spray it and see how it goes. Increase in 5% increments until you find that sweet spot just for you. Keep up with how much you reduced it and next time you will know exactly how much to add and start spraying. 

Most of the time I thin all my sealers and lacquers 15% with butyl acetate and get great results every time.

You can add butyl acetate to NC sealers and lacquers, vinyl basecoats, CAB Acrylics, polyurethanes, pre-cats, and conversion varnishes.


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## Quickstep (Apr 10, 2012)

Thanks all for the advice. 

I just shot a coat thinned 10% with lacquer thinner. It seemed to lay down nice and wet, but it seemed as if the orange peel began to appear as it began to dry. I'll see what happens as it dries. 

I hear what you're saying about acetone; it's the same thing I'd think. The guy who recommended acetone is a well respected guitar builder; he says it lowers surface tension.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> Thanks all for the advice.
> 
> I just shot a coat thinned 10% with lacquer thinner. It seemed to lay down nice and wet, but it seemed as if the orange peel began to appear as it began to dry. I'll see what happens as it dries.
> 
> I hear what you're saying about acetone; it's the same thing I'd think. The guy who recommended acetone is a well respected guitar builder; *he says it lowers surface tension*.


Thinning it period lowers surface tension.......

What you saw with lacquer thinner will be worse with acetone. Butyl Acetate is the way to go and you will never look back.


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## Steve Neul (Sep 2, 2011)

How hot was it when you sprayed the lacquer? It might be in winter you could spray it without thinning it. In summer you may need to thing it quite a bit or if it's very hot you might use some retarder thinner. Retarder thinner will slow the drying time down so the finish can flow out better. 

For the thinner if what you are doing is important it would be better to use the same brand lacquer thinner as the lacquer. Lacquer thinner is a blend of solvents and the chemist at the paint company have formulated the solvent with the right blend for their lacquer.


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## Quickstep (Apr 10, 2012)

It's hot outside here and that influences the temp in my shop, but it's not crazy hot in the shop. It's in the high 70's and humidity is in the high 60's. Good point about the temperature and thinning. I'm beginning to think that spraying full strength is for guys (or companies) that have controlled conditions and people who know what they're doing!  

I got better results thinning 10%, maybe I need to go more. I'm using big box store thinner. Getting Behlen thinner through the mail is expensive because of the hazardous thing, but I guess I'll have to bite the bullet. I also heard of a Behlen/Mohawk product called "Flash Controller". According to the sales literature, it is 
"Used to improve the flow of lacquers and sealers without slowing the drying. Additions of one or two ounces of Flash-Off™ control solvent per gallon of lacquer will eliminate overspray roughness in the finish and improve the overall smoothness. Not a blush retarder."

Anybody ever heard of this?

Thanks again for all the replies.


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## RandyReed (Jul 30, 2014)

Their flash controller is simply BUTYL ACETATE . 

You can go to a sherwin williams paint store and buy butyl acetate. It will go in practically any of the materials i listed above no matter who makes "it"....."it" being lacquer in this case.

As I said in post #4 in this thread, Butyl acetate is the best flow additive for many materials as it also does not effect dry times or gloss levels.


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## Quickstep (Apr 10, 2012)

Thanks Randy. I can't wait to give it a try.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> Thanks Randy. I can't wait to give it a try.


If you thinned at 10% with a thinner, you may want to start at 15% and may have to go to 20% with the butyl acetate. 

Most material through SW for example suggest a 15% reduction, and that would also go for other material manufacturers as well.


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## Quickstep (Apr 10, 2012)

Thanks again. I struck out at my local Sherwin Williams store. Any suggestions on where else to try? I found it online, but the shipping is nuts.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> Thanks again. I struck out at my local Sherwin Williams store. Any suggestions on where else to try? I found it online, but the shipping is nuts.


hmmm. I would go back to the SW paint store and have them order it for you. Do you have a SW commercial store near you? I know they have it.


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## Quickstep (Apr 10, 2012)

With some perseverance, I found another nearby SW that had it; hope to get there tomorrow. 

BUT - Before I buy a gallon of the stuff (likely a multi-lifetime supply 
Are Butyl Acetate and Lacquer Retarder the same thing? 

Man, I didn't know I'd need to become a chemist to spray a banjo!


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## RandyReed (Jul 30, 2014)

Quickstep said:


> With some perseverance, I found another nearby SW that had it; hope to get there tomorrow.
> 
> BUT - Before I buy a gallon of the stuff (likely a multi-lifetime supply
> Are Butyl Acetate and Lacquer Retarder the same thing?
> ...


Butyl acetate is a solvent that is used in almost all NC sealers and lacquers, CAB acrylics etc. and it aids in flow out of the material being sprayed. It is the "baseline" of all solvents, meaning it doesnt dry too fast or too slow. It is not a retarder. 

Start at 15% and go from there. You will be happy. 

If you ever need a retarder, obtain some MAK from the SW store as well. You would never need more than 10% of it added to your material. Its also universal, just like butyl acetate. Some people do not like the smell of MAK. If you ever need to speed up the drying time, say in the winter, then you would use acetone.


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## Steve Neul (Sep 2, 2011)

Quickstep said:


> It's hot outside here and that influences the temp in my shop, but it's not crazy hot in the shop. It's in the high 70's and humidity is in the high 60's. Good point about the temperature and thinning. I'm beginning to think that spraying full strength is for guys (or companies) that have controlled conditions and people who know what they're doing!
> 
> I got better results thinning 10%, maybe I need to go more. I'm using big box store thinner. Getting Behlen thinner through the mail is expensive because of the hazardous thing, but I guess I'll have to bite the bullet. I also heard of a Behlen/Mohawk product called "Flash Controller". According to the sales literature, it is
> "Used to improve the flow of lacquers and sealers without slowing the drying. Additions of one or two ounces of Flash-Off™ control solvent per gallon of lacquer will eliminate overspray roughness in the finish and improve the overall smoothness. Not a blush retarder."
> ...


High 70's is hardly hot for lacquer. I work in conditions of low 100's. In your case I think thinning with regular lacquer thinner is enough. Every gun has it quirks and that companies lacquer may spray in some guns without thinning it and other guns need a little thinner. Also it's more likely to need to thin using a HVLP sprayer than a siphon sprayer.


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## Quickstep (Apr 10, 2012)

RandyReed said:


> Butyl acetate is a solvent that is used in almost all NC sealers and lacquers, CAB acrylics etc. and it aids in flow out of the material being sprayed. It is the "baseline" of all solvents, meaning it doesnt dry too fast or too slow. It is not a retarder.
> 
> Start at 15% and go from there. You will be happy.
> 
> If you ever need a retarder, obtain some MAK from the SW store as well. You would never need more than 10% of it added to your material. Its also universal, just like butyl acetate. Some people do not like the smell of MAK. If you ever need to speed up the drying time, say in the winter, then you would use acetone.


 
Sorry to keep beating this horse, but I really do appreciate the advice.

When you talk about using Butyl Acetate are you talking about using that instead of thinner, or in addition to thinner?


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## Quickstep (Apr 10, 2012)

Steve Neul said:


> High 70's is hardly hot for lacquer. I work in conditions of low 100's. In your case I think thinning with regular lacquer thinner is enough. Every gun has it quirks and that companies lacquer may spray in some guns without thinning it and other guns need a little thinner. Also it's more likely to need to thin using a HVLP sprayer than a siphon sprayer.


 
Thanks Steve. I'm just getting used to a new gun that is a gravity feed HVLP (conversion, not turbine). I also have an older siphon feed gun. I'm curious to know more about how/why a siphon gun behaves differently. I would have thought that a siphon feed gun would need the material to be thinner than a comparable gravity feed gun since the material in a siphon feed needs to get sucked up from the cup.


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## Hammer1 (Aug 1, 2010)

Quickstep said:


> I feel like I've got the adjustments set and practice on cardboard looks good, but when I spray on my wood practice piece I get pretty serious orange peel. I stepped up to the next tip size and the orange peel is as bad or worse than with the smaller tip. I guess I'll try thinning next.


Orange peel is often caused by the gun being too close to the work and putting on too much material. Back off and don't try to do a perfect coat each time, go light. 90% of spraying is gun technique, it has nothing to do with thinning, which can cause other problems.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> Sorry to keep beating this horse, but I really do appreciate the advice.
> 
> When you talk about using Butyl Acetate are you talking about using that instead of thinner, or in addition to thinner?


1. Use butyl acetate by itself, you dont need lacquer thinner.......I hardly ever use lacquer thinner as sometimes in the summer it aids in speeding up the drying times.

2. If you need it to dry slower, (say your getting over spray in areas), use MAK at no more than 10% along with the butyl acetate.

3. If you need it to dry faster, use acetone, but no more than 15% by itself. Any more added and you may risk the gloss going up soomewhat.


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## Quickstep (Apr 10, 2012)

"Any more added and you may risk the gloss going up soomewhat."

Risk the gloss going UP?

There's no such thing as too much gloss, is there??


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## woodnthings (Jan 24, 2009)

*MAK... abbreviated ?*



RandyReed said:


> 1. Use butyl acetate by itself, you dont need lacquer thinner.......I hardly ever use lacquer thinner as sometimes in the summer it aids in speeding up the drying times.
> 
> *2. If you need it to dry slower, (say your getting over spray in areas), use MAK at no more than 10% along with the butyl acetate.
> *
> 3. If you need it to dry faster, use acetone, but no more than 15% by itself. Any more added and you may risk the gloss going up soomewhat.


What is it? I've heard of MEK, methyl ethel ketone ...but MAK?


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## RandyReed (Jul 30, 2014)

Quickstep said:


> "Any more added and you may risk the gloss going up soomewhat."
> 
> Risk the gloss going UP?
> 
> There's no such thing as too much gloss, is there??


Well, that depends. :laughing:


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## RandyReed (Jul 30, 2014)

woodnthings said:


> What is it? I've heard of MEK, methyl ethel ketone ...but MAK?


MAK is Methyl Amyl Ketone. It is a Medium reducer (retarder) that you would use to slow drying times down and especially useful when spraying the inside of cabinets, entertainment centers, etc to avoid overspray.

Its also used for wetter spray and deeper penetration in vinyl basecoat stains as well.


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## epicfail48 (Mar 27, 2014)

Quickstep said:


> There's no such thing as too much gloss, is there??


There is when the can said "semi-gloss"


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## Steve Neul (Sep 2, 2011)

Quickstep said:


> Thanks Steve. I'm just getting used to a new gun that is a gravity feed HVLP (conversion, not turbine). I also have an older siphon feed gun. I'm curious to know more about how/why a siphon gun behaves differently. I would have thought that a siphon feed gun would need the material to be thinner than a comparable gravity feed gun since the material in a siphon feed needs to get sucked up from the cup.


I can't help you there. I bought a HVLP sprayer one time and it put out so little material I threw the gun away and went back to a siphon sprayer. I also worked for someone else briefly and they used a more expensive HVLP sprayer and it worked about the same as the one I threw away. They seem to atomize the finish a lot more than a siphon sprayer which in turn has it going on dryer.


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## Quickstep (Apr 10, 2012)

*Butyl Acetate - How much is too much?*

I got the butyl acetate and shot a couple of coats last night. I tried thinning at 10% the first time. It had minor orange peel, so I shot a second coat thinned to 15%. On the second coat, the orange peel is very, very minimal and it will sand out easily in the final polishing process, BUT,,,, I'm greedy - how far can I go to achieve a glass flat; off the gun finish? How much Butyl Acetate is too much?


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## RandyReed (Jul 30, 2014)

Quickstep said:


> I got the butyl acetate and shot a couple of coats last night. I tried thinning at 10% the first time. It had minor orange peel, so I shot a second coat thinned to 15%. On the second coat, the orange peel is very, very minimal and it will sand out easily in the final polishing process, BUT,,,, I'm greedy - how far can I go to achieve a glass flat; off the gun finish? How much Butyl Acetate is too much?


As much as you want, LOL. Thats the beauty when using butyl acetate. You can thin it to make a flow coat if you wanted too......and a flow coat is 25% lacquer to 75% butyl acetate. Just remember that every time you add more butyl, you are thinning the lacquer, so be careful not to make any runs! Most of the time when doing flow coats it only takes a light coat anyway.

I would try 25% butyl to the lacquer you are shooting and give it a try once you have sanded your previuos coat as flat as you can without sanding through the finish.


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## Quickstep (Apr 10, 2012)

As this thread has progressed and people have talked about the differences between Butyl Acetate and Acetone, I decided to check out the MSDS for Behlen's proprietary reducer. It contains both Butyl Acetate *and* Acetone as well as Isopropanol and Aliphatic Petroleum Distillates. 
Isopropanol is the highest percentage of the mix at 30-50%, Aliphatic Petroleum Distillates is 20-30%, 
Acetone, Ethyl Acetate and Butyl Acetate are all at 10-20%. 

All of these have varying evaporation rates. For example Butyl Acetate's evaporation rate is the baseline at 1.0, wheras Acetone is the highest at 5.7! The others are in the middle. 

I'd love to know how they interact. 

What I'd really love would be to find a place where I could but Behlen's Lacquer Thinner without having to pay a hefty shipping fee on top of the already hefty price!


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## woodnthings (Jan 24, 2009)

*there are several types of lacquer thinner...*

AS I remember lacquer thinner comes in differentg "rates" slow, medium and fast. for various temperature applications: You can also get it on EBay with free shipping from some suppliers:

http://www.ebay.com/itm/CMA-DuAll-P...hash=item3f3a13e3d7&item=271557321687&vxp=mtr

a slow version:
http://www.ebay.com/itm/AUTOMOTIVE-...hash=item4d22c94ae3&item=331296099043&vxp=mtr

Home depot:
http://www.homedepot.com/p/Klean-Strip-1-gal-Lacquer-Thinner-GML170/100198758

OReilly's:
http://www.oreillyauto.com/site/c/detail/DPL0/CM502.oap?pt=N0476&ppt=C0171

Other Brands:
http://www.rustoleum.com/product-catalog/consumer-brands/auto/paint-chemicals/lacquer-thinner/

As far as I know the different blends are a result of the amount of retarder or Buytl acetate, but I don't know for certain.


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## RandyReed (Jul 30, 2014)

woodnthings said:


> AS I remember lacquer thinner comes in differentg "rates" slow, medium and fast. for various temperature applications: You can also get it on EBay with free shipping from some suppliers:
> 
> http://www.ebay.com/itm/CMA-DuAll-P...hash=item3f3a13e3d7&item=271557321687&vxp=mtr
> 
> ...


This is correct. Even reducers are made of different solvent blends. There are also, and some people dont know this, but a normal Naptha and a Slower drying 140 Naptha for example.

Solvents are added to different materials in the formulating stage, in this case lacquer. When the formulator needs it to be faster or slower, they will add the proper solvent to perform what is needed. Thats why there is always a mixture of solvents. Some lacquers start off with acetone for example because its a strong solvent that will dissolve the resin. Others are adding in and then its dialed in to achieve specific drying times, etc. Butyl acetate is always one of the main solvents in lacquer because it is the baseline of all solvents and formulators work off of this to adjust drying times and other properties.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> As this thread has progressed and people have talked about the differences between Butyl Acetate and Acetone, I decided to check out the MSDS for Behlen's proprietary reducer. It contains both Butyl Acetate *and* Acetone as well as Isopropanol and Aliphatic Petroleum Distillates.
> Isopropanol is the highest percentage of the mix at 30-50%, Aliphatic Petroleum Distillates is 20-30%,
> Acetone, Ethyl Acetate and Butyl Acetate are all at 10-20%.
> 
> ...


Thats why I was saying that butyl acetate will help you in the leveling of the lacquer you are spraying without throwing the properties out of whack. Did you ever try to reduce the lacquer with 25% and respray? That should be more than enough to get a level finish.


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## Quickstep (Apr 10, 2012)

I haven't tried 25% yet, but I will. I've noticed though at the nitro continues to cure and shrink, the little bit of orange peel that I had is now almost non existent. It will easily sand out during the polishing process.


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## Steve Neul (Sep 2, 2011)

Quickstep said:


> I haven't tried 25% yet, but I will. I've noticed though at the nitro continues to cure and shrink, the little bit of orange peel that I had is now almost non existent. It will easily sand out during the polishing process.


Yea the more you sand the lacquer and re-spray it with properly thinned lacquer the finish will eventually perfectly level out. You can even fill shallow dents in the wood doing that.


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## Quickstep (Apr 10, 2012)

Back to this......

I just shot a coat thinned 33% with Butyl Acetate. I still have some orange peel. It will sand out, but I really I really thought by the time I thinned this much, the finish would level like glass. Here's the weird thing. Everything happens fast (like in a car accident!), but it almost seems like the finish appears to be level as I spray it and the orange peel appears as it dries. Does this make sense at all?


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## RandyReed (Jul 30, 2014)

Quickstep said:


> Back to this......
> 
> I just shot a coat thinned 33% with Butyl Acetate. I still have some orange peel. It will sand out, but I really I really thought by the time I thinned this much, the finish would level like glass. Here's the weird thing. Everything happens fast (like in a car accident!), but it almost seems like the finish appears to be level as I spray it and the orange peel appears as it dries. Does this make sense at all?


You should not have any orange peel thinned at that amount. 
Without actually being there to watch you spray, its hard to pin point whats going on. More than likely, its your spraying technique. Try speeding up your spray passes because you may be laying down too much material. The only other thing i can think of is adjusting your fluid trigger adjustment screw by turning it in at least 1 turn clockwise to limit the amount of material coming out. Try opening the fan patern some as well by turning the top screw counter clockwise 1/2 turn.


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## Quickstep (Apr 10, 2012)

RandyReed said:


> You should not have any orange peel thinned at that amount.
> Without actually being there to watch you spray, its hard to pin point whats going on. More than likely, its your spraying technique. Try speeding up your spray passes because you may be laying down too much material. The only other thing i can think of is adjusting your fluid trigger adjustment screw by turning it in at least 1 turn clockwise to limit the amount of material coming out. Try opening the fan patern some as well by turning the top screw counter clockwise 1/2 turn.


You're kidding me - altering the material won't overcome my lack of skill?!?

I am moving slowly. And, thanks to my skill level, I want to keep moving fairly slowly, it seems the best way to see what I've covered. The material screw is only out 1.5 turns, so I'll have almost no material if I go in a full turn. 

Just for reference, here's the formula I was using and getting very good, but not perfect results.

1.2 tip
20% Butyl Acetate
fan pattern 1/2 turn (makes about a 5" pattern)
material screw 1-1/2 turn
25 PSI
Gun about 7" from the surface

I used that same setup after thinning 33%, but got the same results. Should I have turned the material down after thinning more?


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## woodnthings (Jan 24, 2009)

*what about the gun?*



Quickstep said:


> Thanks Steve. I'm just getting used to a new gun that is a gravity feed HVLP (conversion, not turbine). I also have an older siphon feed gun. I'm curious to know more about how/why a siphon gun behaves differently. I would have thought that a siphon feed gun would need the material to be thinner than a comparable gravity feed gun since the material in a siphon feed needs to get sucked up from the cup.



I have been spraying all week long, PPG epoxy primer with hardener and PPG onestep top coat with hardener. using cheap Harbor Freight HVLP gun, the $15.99 one purple... you know the one. It came with a 1.4 tip.

So, it's primer, a bit heavy, but it goes on well, flows out and dries with no orange peel. Pressure at the gun about 40 PSI, pattern about 5" wide, volume control about 2 turns out, moving very quickly side to side and edging vertically where that is required.......

These are large flat steel panels 24" X 72" and 30" X 72" . You gotta keep that gun moving quickly enough that the volume of paint will not build up enough to run on vertical surfaces. I use the same speed on horizontals, maybe a bit slower so I can build it up 
a little more.

I don't know what else can to be done to cure your issue. The paint has a consistency of a nice, rich chocolate milk as best I can describe it. I know epoxy is not lacquer, but I don't think that matters too much. 
Viscosity is a science unto itself and without a means to measure it, ya just gotta go by what works. Start out thicker, and thin until it works. :blink:


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## Quickstep (Apr 10, 2012)

For what it's worth, My test piece is horizontal, but before I shoot on the test piece, I spray on a piece of cardboard to see how wide the pattern is. The cardboard is vertical and on my pre-test spray, I seem to be getting a nice wet coat without any sags or runs, leading me to believe I've got the fluid setting nailed. Even thinned 33%, this stuff seems to be drying fast. It's dry to the touch in under 10 minutes. 

Now mind you, the orange peel I'm seeing is minor, certainly less than an actual orange. It easily sands out, but I'd sure like to be able to improve either my technique or chemistry to get that glossy off-the-gun finish.


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## Steve Neul (Sep 2, 2011)

I don't really know. I quit using HVLP sprayers years ago. I've bought three and shelved the HF purple gun threw the other two away because they don't put out near the volume a siphon sprayer does. I do know the HVLP sprayer has baffles in it which lowers the air pressure at the nozzle.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> You're kidding me - altering the material won't overcome my lack of skill?!?
> 
> I am moving slowly. And, thanks to my skill level, I want to keep moving fairly slowly, it seems the best way to see what I've covered. The material screw is only out 1.5 turns, so I'll have almost no material if I go in a full turn.
> 
> ...


Too little air pressure will cause the drops to be too big and result in drops that may not be able to flow into each other. This will cause a heavy orange peel effect. Since you are saying you are getting small orange peel, I would still bump the air pressure up to at least 35-40 psi and try that.

Even though HVLP guns spray at 10 psi through the air cap, you still should set the psi around 40-50 psi at the compressor or cheater valve going into the gun. I bet that will solve your problem. If that doesnt work, the only other solution would be to speed up your passes slightly.


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## woodnthings (Jan 24, 2009)

*exactly!*



RandyReed said:


> Too little air pressure will cause the drops to be too big and result in drops that may not be able to flow into each other. This will cause a heavy orange peel effect. Since you are saying you are getting small orange peel, I would still bump the air pressure up to at least 35-40 psi and try that.
> 
> Even though HVLP guns spray at 10 psi through the air cap, you still should set the psi around 40-50 psi at the compressor or cheater valve going into the gun. I bet that will solve your problem. If that doesnt work, the only other solution would be to speed up your passes slightly.


This is my experience also. I had too little pressure at the gun. I mounted a gauge and adjustment control on the gun, set the line pressure at the tank to 50, and then back it off at the gun to 40 or so.










I also recommended making faster passes. You gotta have decent and sufficient light to reflect where the wet coat is so you can overlap and get a good flow out. I've been working outside lately in the shade, but there is a good reflection in the wet surface to work with. 

There has to be an answer.... :yes:


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## epicfail48 (Mar 27, 2014)

Quick question, are you sure what youre getting is actually orange peel, and not something that looks similar like fish-eyes? Thinned out that much, nearly anything should flow out to a glass smooth surface, regardless of your spray ability. At any rate, the problem doesnt seem to lie with finishing to much as technique. 

http://www.how-to-build-hotrods.com/set-up-hvlp.html
I know you said you ran a test shot before hand, but still, that link is worth a read. Explains how to perfectly set up the gun


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## RandyReed (Jul 30, 2014)

Yes, i think if he goes from 25 psi to 40-50 psi, that should solve his problem. He probably doesnt have enough air at the cap to atomize the lacquer properly. At 50 psi, he should be able to reduce the lacquer 20-25 % tops and have good flow out. Anything over 25% is taking too much of the solid content away from the material.


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## Quickstep (Apr 10, 2012)

*Oops!*

I should have written I'm using 30 PSI, not 25. 30 is what the manufacturer recommended. Never the less, it seems like I should crank it up a tad. 

So, is it fisheye or orange peel?....... When I think of fisheye, I think of randomly distributed craters. This isn't like that. It's uniform across the board. The lacquer I'm spraying is Behlen Stringed Instrument Lacquer and I'm wondering if it behaves differently than other lacquer. This stuff really seems to shrink as it cures. When I wrote yesterday, I reported that I had fine orange peel. Today, that orange peel is all but gone, so clearly this stuff keeps shrinking long after it's dry to the touch. 

I do have some concerns about my air. I have a separator at the compressor and an inline water/oil filter at the gun. I sprayed air into a container filled with water to see if any oil would show up on the surface, but didn't see any. I do see oil in the water when I drain the tank from the bottom though. I'd welcome any other tests I should run to determine if my air is contaminated. 

Getting ready to shoot another test coat at higher pressure. More to follow......


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## woodnthings (Jan 24, 2009)

*I'm still wondering...*

I don't want to reread all the previous posts, but did you say what gun you are using?










This is the HF 47016 gravity feed HVLP at $15.99 that I use. I found it to be all I need even though I have other pressure feed guns as well. So I bought 3 or 4, but so far with very methodical cleaning, the first one still works fine. 
Here's what I found out. The control on the base of the gun where the air inlet is, is crucial in getting the proper air flow through the gun. Too little volume, it comes out dry or it just burps out in a drool. Too much volume and you get lots of product and overspray. I adjust it "dry" so when I pull the trigger the gauge stays at about 40 PSI, and when filled, sprays a good even pattern.


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## Quickstep (Apr 10, 2012)

I'm using the QS125 from Homestead Finishing. A link is below. 

One of the guys on a guitar builder's forum says that orange peel is a fact of life with an HVLP gun. Maybe I need to resign myself to that.......


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## woodnthings (Jan 24, 2009)

*This one*

http://homesteadfinishingproducts.com/products-we-offer/hvlp-spray-equipment/qualspray-hvlp-guns/

The QS 125 seem like a great gun to me. The only issue I see it's described as a detail gun?










That may be an issue, I donno?

*QS-125WB* – We asked our factory to design us a radically different detail gun that could act like a larger one when it came to spraying waterborne and solvent-borne clears. Now you can get a gun that’s just as good as spraying thinner viscosity finishes for touch up and detail work, and spray clears without thinning. This new addition has an all stainless steel finish travel path (see description below for QS-600WB), in addition to the stainless used on the nozzle and needle. Plus it only needs 4 cfm to run. The 1.2mm will spray clear finishes without thinning unless they are pretty thick. The 125cc cup will hold about 4 ounces of finish, but larger cups are available as an optional upgrade if you need it. Spray Gun comes with a 2 year warranty. We beta-tested this gun with several customers. Read what one said:


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## Quickstep (Apr 10, 2012)

Yes, it's a small gun. It sprays a pattern from about 4" up to about 8". I'm spraying banjo parts, so the spray pattern size is perfect for my needs.


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## Quickstep (Apr 10, 2012)

I shot another coat last night with a 1.1 tip; 35 psi and material thinned 25% with Behlen's proprietary reducer. Like the other coats, it looked nice and wet as it went on, then looked like the face of the moon, then began to level. By this morning, it's pretty glassy looking. The Behlen Stringed Instrument Lacquer seems to behave differently that other lacquers based on what I've read. It seems to continue to level as it cures. What looks kinda lumpy at first seems to level out in a day. This is probably why they recommend waiting 2 weeks to polish it out. 

I read instructions on a Lutherie website where they recommend thinning the first several coats 50%, followed by build coats thinned 25% plus 5% retarder and the final coats thinned 33% plus 10% retarder. Not sure what there is to be gained by varying the amount of thinner, but I'm sure there's a method to the madness. 

I'm trying to find a formula that works consistently since I'll always need to sand at least a little bit between coats.


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## Steve Neul (Sep 2, 2011)

Quickstep said:


> I shot another coat last night with a 1.1 tip; 35 psi and material thinned 25% with Behlen's proprietary reducer. Like the other coats, it looked nice and wet as it went on, then looked like the face of the moon, then began to level. By this morning, it's pretty glassy looking. The Behlen Stringed Instrument Lacquer seems to behave differently that other lacquers based on what I've read. It seems to continue to level as it cures. What looks kinda lumpy at first seems to level out in a day. This is probably why they recommend waiting 2 weeks to polish it out.
> 
> I read instructions on a Lutherie website where they recommend thinning the first several coats 50%, followed by build coats thinned 25% plus 5% retarder and the final coats thinned 33% plus 10% retarder. Not sure what there is to be gained by varying the amount of thinner, but I'm sure there's a method to the madness.
> 
> I'm trying to find a formula that works consistently since I'll always need to sand at least a little bit between coats.


I know this has been discussed but what you are describing sounds like fisheye. This sounds pretty far fetched though. Fisheye is normally caused by silicone in spray wax like pledge or if silicone spray lubricants are used in the shop. The boards you are spraying is it possible a wax like that has been sprayed around them? Fisheye can also be caused by oils or soap but not as likely. If the initial spray was good there has to be some contamination of some kind somewhere. Orange peal would be immediate. There should be a crusting with it too that has a roughness like sandpaper. 

Lutherie recommends thinning the first coat 50% because it penetrates deeper into the wood and makes a better bond. This is true to an extent but lacquer is sprayed thin enough anyway and will penetrate into the wood deep enough that you don't experience adhesion problems anyway.

As far as pressure I use 40 psi with all the guns in my shop for a film finish. The only time I use a lower pressure is when I spray a dye stain. 

They recommend waiting two weeks so the finish can cure before polishing. There is a difference between the finish drying and coming to a full cure. If you polish it too soon the wax can get into the finish instead of laying on top.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> I shot another coat last night with a 1.1 tip; 35 psi and material thinned 25% with Behlen's proprietary reducer. Like the other coats, it looked nice and wet as it went on, then looked like the face of the moon, then began to level. By this morning, it's pretty glassy looking. The Behlen Stringed Instrument Lacquer seems to behave differently that other lacquers based on what I've read. It seems to continue to level as it cures. What looks kinda lumpy at first seems to level out in a day. This is probably why they recommend waiting 2 weeks to polish it out.
> 
> I read instructions on a Lutherie website where they recommend thinning the first several coats 50%, followed by build coats thinned 25% plus 5% retarder and the final coats thinned 33% plus 10% retarder. Not sure what there is to be gained by varying the amount of thinner, but I'm sure there's a method to the madness.
> 
> I'm trying to find a formula that works consistently since I'll always need to sand at least a little bit between coats.


Although I never used it, it seems they want to slowly build up the dry thickness by reducing 50% before applying the build coats reduced 25% as they suggested. They do this so that the finish doesnt crack due to too much build with all the coats, and once you go through the steps you have a slick finish that can easily be polished out.

On the other hand, I dont know why they suggest this in the first place. Their lacquer is nitrocellulose and you can simply use 2-3 coats of a high build sealer, then 2-3 coats of a high gloss lacquer and get the same results. The fact that people say furniture lacquer and instrument lacquers are 2 different things is a myth. Even furniture lacquers used today have plasticizers in them, and they will expand and contract with the wood.


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## Quickstep (Apr 10, 2012)

Just FYI, the thinning recommendation from the Lutherie website is for lacquer coats applied after vinyl sealer. 

I am concerned about contamination as the cause. 

There's no wax or other stuff in the area. I'm sanding using wet or dry paper lubricated with naphtha. I wipe it clean with naphtha and let it dry before spraying. 

My (old) compressor has a separator at the compressor and I have a oil/water filter at the gun. I use only 15' of hose. But, I wonder if water or oil is still getting through. I don't know how much more filtering I can do without restricting air flow.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> Just FYI, the thinning recommendation from the Lutherie website is for lacquer coats applied after vinyl sealer.
> 
> I am concerned about contamination as the cause.
> 
> ...


Have you been doing these adjustments in this post on the same piece of wood? I would try another piece of wood and thin the lacquer coat at 35% and see if it flows out right. I would even thin the sealer coats back 25% and apply 3 thin coats before moving on to the lacquer.

Wipe the wood down good with naptha before applying the sealer. Since its a vinyl sealer, *applying thin coats instead of heavy coats* will help if there is contamination.


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## Steve Neul (Sep 2, 2011)

Quickstep said:


> Just FYI, the thinning recommendation from the Lutherie website is for lacquer coats applied after vinyl sealer.
> 
> I am concerned about contamination as the cause.
> 
> ...


I don't think I would be using naphtha with between the coats sanding. If you are going to wet sand I would use water as a lubricant. Personally I don't wet sand lacquer between coats, I dry sand only. Glit or 3M makes sponge rubber pads for sanding which work very well. 

There is the potential of contamination from oil in the air but your compressor would have to be in pretty bad condition to put enough oil in the air to cause you that much trouble. I had one that put enough oil in the air to make the finish cloudy when multiple coats were applied but it wasn't enough to cause fisheye. If there is no contamination from anything in your shop I would think along the lines the finish you bought was defective or old. You could find this out by buying another brand of lacquer from someone else and see how it sprays. Another option to finding out if it is contamination would be to go to a store that sells automotive finishes and buy a bottle of smoothie. A couple drops of that in the finish would eliminate any silicone problem. The bad of it is smoothie is silicone so you have to use a little care spraying it to keep from contaminating something else. For example if you sand a finish that has smoothie in it and a month later forget and use the same sandpaper to sand something else then that project is contaminated with silicone and the lacquer you spray on it will have to have the smoothie additive to make it work.


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## Quickstep (Apr 10, 2012)

I appreciate you guys continuing to post up with suggestions throughout this journey. 

My compressor is OLD. I did shoot air into a container of water to see if it made an oil slick on the top, and I didn't see any. I also shot air into my hand and my hand didn't get anything but dry; I didn't feel any oily feel. Is that good enough?

Sanding - This lacquer won't sand dry using 320 or higher grit. It just makes corns on the paper. It's better with water, but still makes some corns. It seems like naphtha works best, which is why I have been using naphtha. I've always thought naphtha left no residue behind once dry. 

Yes, it's the same board. It's got a couple of dozen coats by now. I initially shot 2 coats of the recommended vinyl sealer, followed by all the tests I have done so far. Before the last test coat, I actually sanded the lacquer coats using micro-mesh all the way to 12,000 grit. It looked beautiful. I stopped short of polishing just in case the polishing stuff might have silicone in it. So, I know it will polish up, I'm just trying to get better off the gun.

I just started my second quart of finish with no change in results.


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## Steve Neul (Sep 2, 2011)

Your testing of the air is enough and clever running it into water. From your description I think it passed the test. 

If the lacquer is balling up on the sandpaper when sanding then either something is wrong with it or it's not dry enough for sanding. It should sand to a powder when dry sanding. As far as the naphtha any chemical has the potential of leaving a residue. Put some on a piece of glass and allow it to dry and see what is left. 

Couple dozen coats huh. You know lacquer melts into previous coats so the more coats you put on the longer drying time between coats it needs. The lacquer I use recommends an hour between coats. I use a system where the first coat I allow an hour. The second coat gets two hours drying time and so on. This prevents the finish from getting soft and gummy in the middle. I've sanded lacquer before that had a lot of coats and sanded down to a soft layer underneath and had the lacquer gum up and pull out a big plug of lacquer leaving a hole. This is when I came up with this system of drying time. 

I don't know about that brand you are using but a single coat of vinyl sealer is enough for me.


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## RandyReed (Jul 30, 2014)

If the lacquer is gumming up when you sand it, its not properly dried. The sealer and lacquer should sand pretty easily with 320 grit.


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## woodnthings (Jan 24, 2009)

*I wouldn't be using the same "test" piece*

You don't know what's going on under all that. To run a controlled test you have to control all the variables except one. So it would help to start on a fresh piece and then run your tests for viscosity and so forth.


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## Quickstep (Apr 10, 2012)

The stuff I'm using is Behlen Stringed Instrument Lacquer. It's described as:

A hard, durable finish that's less brittle and more flexible than standard furniture lacquer.

Stringed Instrument Lacquer is specifically formulated to accommodate the expansion and contraction of wooden instruments.

Stringed Instrument Lacquer finish has better resistance to cold-checking and scuffs than standard furniture lacquer. It's ready to spray with no thinning required, for faster finish build-up in multiple coats. This lacquer is designed for use on wood which has been sealed with Behlen Vinyl Sealer, or on unfinished wood.

My guess is that it's softer and that may be why it's harder to sand. Based on what I've seen so far, I don't think it would sand to powder unless it dried for a couple of weeks


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## Steve Neul (Sep 2, 2011)

I've never used that product, still I don't think it would be that soft. I think it may be the amount of coats and the retarder thinner that is slowing down the cure time. The product instructions say it will sand to a powder.


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## RandyReed (Jul 30, 2014)

Like i said, the statement that says instrument lacquer has better resistance to cold checking and scuffs over furniture lacquer is a myth. One of the tests performed on regular lacquer is cold check resistance. We manufacture the lacquer for fender and gibson guitars. Only difference is the lacquer has higher grade materials in the formula that support higher build coats that can be applied without cracking the finish. In the end, you can apply up to 8-9 coats of instrument lacquer and buff it out, where as you can only safely apply 4 coats of furniture lacquer and buff it out without a chance of cracking the finish. Once done, it will look the same and perform the same as the instrument lacquer.


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## Steve Neul (Sep 2, 2011)

Believe it or not the worst lacquer I ever used that was bad about cold checking was Dupont Furinture Lacquer.


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## RandyReed (Jul 30, 2014)

Modern finishes can crack when applied past their maximum dry film thickness. They also can crack due to a cold climate below 65 degrees before they have had their 48 hour cure time and some finishes can crack if you use more than the suggested amount of catalyst. Some pre-cat lacquers have a max dry film thickness of only two mils, and this is why its important to know how many wet mils a finish should be applied at.

If you see white lines in the cracks than this is the wood that is checking and not the finish itself.

Our "instrument lacquer" (which simply states is formulated for coating interior woodworking.....like all other NC lacquers) is designed to go on 4.0-6.0 wet mils and drys down to 0.60 - 0.90 dry mils. Maximum dry film thickness for the total finish system is 10.0 mils, so in theory, you can apply roughly 10 coats of this lacquer and have no cracking.

As long as the lacquer has good flexibility at high build, then it will expand and contract with the wood, which most nitrocellulose lacquers of today will do.


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## Quickstep (Apr 10, 2012)

So, Randy, can you tell us who "we" is? I'd happily change brands. I had assumed Gibson used Cardinal or Seagraves.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> So, Randy, can you tell us who "we" is? I'd happily change brands. I had assumed Gibson used Cardinal or Seagraves.


Sure, Gibson uses Sherwin Williams. Product is SHER-WOOD® GLOSS LACQUER T75CH56. Not sure if they use all SW, or when they switched, but I do know they were applying this coating in May of 2014.


T75CH56 is a gloss nitrocellulose
lacquer. This product is formulated for
coating interior woodworking. 

*Advantages:*
1. Good flexibility at high build.
2. HAPS Compliant.
3. Excellent rubbing characteristics.
4. Water White.

*Product Limitations:*
1. Not recommended for exterior
application.
2. Agitate before and while using,
only gentle agitation is required.
3. Maximum dry film thickness for
the total finish system is 10.0
mils.

*APPLICATION*
Apply by HVLP, Conventional, Airless, or
Air Assisted Airless.

Recommended Film Thickness: Total
dry film thickness for entire finishing
system should not exceed 10.0 dry mills
after buff and polish.
Mils Wet: 4.0 - 6.0
Mils Dry: 0.60 - 0.90

Reduce: Reduce as required with
Butyl Acetate R6K18 up to 10%. to
maintain HAPS compliance.

Retard: Use R6K35 - EEP up to 5% to
maintain HAPS compliance.


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## Quickstep (Apr 10, 2012)

I've always heard good stuff about Asher-wood lacquer, but had no idea it was used in guitars. I wonder if anyone is using it on acoustic guitars. Have you heard anything about that?


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## RandyReed (Jul 30, 2014)

Quickstep said:


> I've always heard good stuff about Asher-wood lacquer, but had no idea it was used in guitars. I wonder if anyone is using it on acoustic guitars. Have you heard anything about that?


You mean Asher guitars? Asher uses a nitrocellulose lacquer. However, I dont know the manufacturer in which they use.


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## Quickstep (Apr 10, 2012)

I meant to write Sher-Wood lacquer. 
Seems like spell check is biting me more often than not.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> I meant to write Sher-Wood lacquer.
> Seems like spell check is biting me more often than not.


Oh, gotcha! 
I have no idea about acoustic, but I dont see why not. Acoustic guitars have a nitrocellulose coating, and some are polyurethane. I would think that the thickness of the coatings may/will impact the overall sound on an acoustic, but Im not sure. That may be something you want to find out/ask on a guitar forum.


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## Quickstep (Apr 10, 2012)

RandyReed said:


> Oh, gotcha!
> I have no idea about acoustic, but I dont see why not. Acoustic guitars have a nitrocellulose coating, and some are polyurethane. I would think that the thickness of the coatings may/will impact the overall sound on an acoustic, but Im not sure. That may be something you want to find out/ask on a guitar forum.


I think thickness is a factor, but maybe not as big as people might have you believe. I think the goal is to put on just enough to be able to rub it out. That's some of the reason behind my desire to get a better "off the gun" finish.


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## RandyReed (Jul 30, 2014)

The specs i posted above for the sherwood lacquer is what it is. If you follow that, you should be good to go.


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