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View Full Version : Acrylic Lacquer .... ?



Dennis Peacock
07-08-2015, 9:54 AM
Will an auto paint & clear coat buff out for a guitar gloss finish? Edumuhcate me. :)

Mike Sherman
07-08-2015, 11:02 AM
Yes! In the early days, Fender and Gibson were using automotive Acrylic for their finishes. It has more plasticisers and flex agents in it to make it more durable for the wide heat range conditions cars experience. If used, you should follow the same regimen as spraying nitro (number of clear coats, ect..).

Edit: I should add that urethane auto paint will also give good results if applied properly. Urethane is used by most auto body shops for its fast drying time.

I would avoid using single-stage auto paint as it catalyzed and usually applied in two coats.

Curt Harms
07-10-2015, 7:10 AM
Dennis, if you're able to lay your hands on the June 2015 Woodworker's Journal, Michael Dresdner has an article about guitar finishes and their history. Executive summary - automotive finishes can be used on guitars.

george wilson
07-10-2015, 9:32 AM
Acrylic lacquers have a cold look to them that I definitely do not like. This is because the resin they are made from is bluish in color. Nitro is made from a yellowish resin and is much more warm in color.

Acrylic is supposed to be superior to nitro in several respects,but I don't like the coldness. Martin guitars apparently use acrylic,and they do not have the warmth of their older instruments. Whatever they are using,it doesn't look warm.

It was suggested to me by a very knowledgeable person who used to be in charge of restorations of metal objects in the museum,to add some yellow dye to acrylic to get rid of the cold blue tint. I have not tried this since I still have some nitro left on my shelves. I am also wary of dyes fading over time,and then having that cold color come back.

If you try this,be sure to use a DYE(which is transparent),and not a pigment(which is opaque). I'd spray a test piece first with several coats,and see if it looks warm or cool before committing to a guitar.

Raphael Weil
10-04-2015, 2:25 PM
If you do apply it on a guitar I'd love to see a picture. So curious how that would turn out.

Warren Lake
10-06-2015, 1:05 AM
you can still get acrylic lacquer? not up in Canada from the auto suppliers for a long time. Its soft and hard at the same time. Ive used it on furniture in the distant past. Last time dealing with it I repolished a black piece from the past, came out like a mirror. Nice but it scratches easily.

George I worked in a music store in the late 70's and we sold new and used Martins and other acoustics and electrics. I remember the used Martins (older ones) had that nice yellow you talk about think they were Nitrocellulouse. I can remember old D-18's that sounded better than new D28's but cant remember the clear coat colour, too far back for me. I think people doing custom acoustics at least some are using post cat high gloss lacquers and think its on some pretty high end acoustics. It would be stronger than acyrilic lac and easily available. You could probably use a pre cat as well approx 10 percent not as hard as post cat if I remember correctly and ive seen that amber colour in post cats like Becker has. Facett I think it was. It was more like Nitrocellulose just an upgrade. Nitrocellolouse had a beautiful look to it.

george wilson
10-08-2015, 9:31 AM
These new finishes like the poly finishes are applied too thick,and hurt the tone immeasurably. They are o.k. for electric guitars(but STILL have a cold,glassy,plastic look about them).

I am TOTALLY UNAWARE that Gibson in the early days used automotive finishes. They used nitrocellulose lacquer. Fender,on the other hand(who were not really what I'd call EARLY),DID start using automotive solid colors in the 50's. Gretsch did too,on their electric guitars. They used Cadillac green on their Country Club model-as well as the more traditional sunburst and blonde finishes of nitrocellulose,for example.

The use of lively automotive colors was a good selling point for Fender and Gretsch electrics. To the rock and roll crowd,the old sunburst finishes were looking stodgy by then,and the bright colors showed up well on stage.

Today,a BLONDE finish on an acoustic guitar makes it a lot more valuable. It was not done as often as sunburst finishes because the workmanship and the wood had to be perfect. I have actually refinished old Gretsch guitars(Which were most often made of plywood),and found that the outer layer of veneer had been sanded through! The cross grained middle layer was seen . It was over 2" wide!! No problem !!,they had just shaded the guitar very dark over that area!! There were other instances where such FOLLY precluded me from removing a shaded finish and making the new finish blonde for customers who had wanted that conversion.

Dennis Peacock
10-26-2015, 4:34 PM
Status update.....
I chose to apply a Chrysler Pearl Blue and then top coat with clear. The last coat of clear was applied this past Friday. I think it looks really good....for a painted body. :)

Rollie Kelly
01-28-2016, 7:01 AM
Could shellac be used on a guitar or is it not durable enough?
Rollie

Don Parker
01-29-2016, 6:46 AM
I build acoustic guitars, and shellac is the only finish I use. There is some skill involved in the application. You can spray it, but I think French polishing works better. It sounds great, looks great, feels great, and you don't put yourself at risk putting it on the guitar like you do with other finishes. The solvent is alcohol, and the solid is edible. I consider it to be the perfect finish for a fine musical instrument.

On how durable it is: it will show wear and tear easier than nitro or the more modern synthetic finishes. But it also repairs far easier than those other finishes. Plus, as the guitar ages, all finishes are going to have issues. The wood moves around over time. A finish that can be easily renewed is a nice thing over the long haul.

george wilson
02-19-2016, 8:57 AM
Don,you might find that over time,or from excessive use,perhaps in warm,humid conditions,your guitar necks will start having their shellac finished screwed up. Also, lacquer finishes are quite easy to repair. They "weld" themselves back together if there are cracks in the finish. Just apply lacquer thinner to any damage,and it will soon disappear. The older a guitar's finish is,the slower it will weld back together.

I will also say that leaving a capo on a shellaced neck might prove disastrous.

I have french polished many of my flamenco guitars. But,I only apply a very THIN coat to the neck to avoid capo damage.

Don Parker
02-19-2016, 11:04 AM
George--

I have some guitars I French polished a number of years ago (one about 20 years ago now, a few others about a decade old), and none of them has experienced the neck problems you have described. I live in West Virginia, which has plenty of humidity swings (high in the summer, low in the winter), and I use capos all the time. Again, no problems.

There are any number of reasons why you might have had the kinds of trouble with shellac that you describe. Did you use canned shellac, or freshly made from flakes? What oil (if any) did you use as a lubricant during application? There are ways that the finish can go wrong. I guess body chemistry can be a factor for some folks, too. But if a person uses freshly made shellac, and applies it well, and takes care of the guitar, there is no reason why a shellac finish cannot hold up pretty well over time.

george wilson
02-19-2016, 1:30 PM
Don,you don't know who I am. Retired master musical instrument maker at Col. Williamsburg. 40 years there,building since 1954. Only a newbie would use canned shellac. I use only flakes.

In reality,shellac is the cheapest finishing material ever conceived of.

Don Parker
02-20-2016, 12:08 AM
Didn't mean to offend you, George. You obviously know what you are doing. But wouldn't you agree with me that lots of fine guitars are finished with shellac, applied via the French polish method? I just don't see it as an inferior finish compared to nitro; merely different. And certainly less dangerous for the finisher than nitro.

george wilson
02-20-2016, 10:25 AM
I used french polish on my flamenco guitars for several reasons: The dirt poor Spanish makers had nothing else to use,so it's traditional; A very thin finish makes for better tone; Flamenco guitars in the true sense do not have as bright a finish as classicals(at least TODAY's classicals do.

The trouble with shellac is,by itself,going to lose its brightness in a fairly short time. Even in the 17th. C.,there was a treatise written,which I have read. I forget who wrote it. But,it talks about how BAD shellac finished are. And,it mentions that shellac does not hold it's gloss,so it is an "untrustworthy"(or words to that effect) finish.

In 1974 we made a movie about making a spinet harpsichord and a violin in the 18th. C.. Someone has now put it on you tube. Google George Wilson harpsichord,and you can see it,made into 6 parts,IIRC. We finished the spinet with shellac,and it was very bright when rubbed out. It became dull after several months. We did not use mastic or any other ingredients,just Super Blonde shellac due to the time element. 5 people in the film crew standing around waiting for varnish to dry was not practical because we had to finish the film in the Winter months. It is VERY hard to find a quiet moment to film due to people walking by,busses going by every ten minutes,and the infernal dinging of bicycle bells. They rented bicycles in the Summer. Today is a noisy period of time compared to the 18th. C. Oh,yes,helicopters from nearby military bases and aircraft,too.

The only shellacs I have found that DO retain their glosses are the seed lacs. I like Siam seedlac. But,seedlacs have color in them. They work well,though. I made a little oak cupboard that is attached to the side of my milling machine,to hold small tooling. It is still bright as it was in 1986,when I made it and French polished it with seedlac.

While classical guitars are often seen with orangish colored tops(Thanks to Ramirez. His finishes look like they have mercurochrome dissolved in them!) Whatever dye he uses,it is MOST unattractive and metallic looking. But,I never see flamenco guitars looking like that. And,you did not see that in old guitars made in Spain either.

I was honored by Sabicas in 1967,when he accepted a guitar I made.

As for dangerous,I have COPD now. Probably some of it from breathing lacquer fumes over many years. But,breathing alcohol,especially denatured alcohol fumes are not the greatest thing either. My wife was using denatured alcohol with borax dissolved in it to coat silver jewelry she was making(and still is). She started getting sick and I made her get a license to buy grain alcohol(THAT took MONTHS!) Happily,we soon figured our a way to avoid coating the work with borax during soldering(it was to avoid getting a coating of oxide on the silver when it was red hot).

Don Parker
02-20-2016, 1:34 PM
George--

All of that is interesting, and it definitely shows you have lots of fascinating experience. My core question, though, was: wouldn't you agree with me that lots of fine guitars are finished with shellac, applied via the French polish method? My point in asking that question is that Rollie asked if shellac can be used to finish a guitar. The answer, of course, is yes. Lots of guitars have been finished with shellac, including great guitars by great makers. There are downsides to using it, and there are upsides, too. Just like with any finish. But I am not alone in my opinion that it is a great finish for acoustic guitars. You are describing shellac as if it is the unwanted stepchild of guitar finishes. That is your view, and your view is certainly the product of extensive experience. But it is not a universally held view. I'm asking you to agree with me on that point, in order to paint a fair picture of how the larger community of instrument makers feels, not just how you or I feel.

Regarding the comparison of the relative dangers of the solvents in nitro versus the solvent used to dissolve shellac: I'm sorry, I mean no disrespect, but you really can't compare the two. I agree that using grain alcohol is better for you than using denatured alcohol, and there are different types of denatured alcohol; some are worse for you than others. But, come on; all types of alcohol used for guitar finishing are far, far safer for the human body than the stuff that goes into nitrocellulose lacquer. Nobody wears a hazmat suit and a VOC filter mask, and works in a room with an explosion proof fan, in order to French Polish a guitar, but you would be pretty reckless to spray nitro without all of those things.

I'm sorry about your COPD. I lost both my parents to breathing disorders. It is frightening and frustrating to be unable to breath. This is one of the reasons I don't spray any finish, and why I French polish my guitars using Everclear. They sell it over the counter in liquor stores in Kentucky, by the way, in case you ever make it over that way.

george wilson
02-21-2016, 9:50 AM
I wear an appropriate mask when spraying nitro these days.

Allan Speers
04-17-2016, 6:52 PM
Didn't mean to offend you, George. You obviously know what you are doing. But wouldn't you agree with me that lots of fine guitars are finished with shellac, applied via the French polish method? I just don't see it as an inferior finish compared to nitro; merely different. And certainly less dangerous for the finisher than nitro.

My feeling is that french polish is the ultimate finish for a guitar TOP, but not for the neck. George is correct: (he pretty much always is) Shellac can get messed up from warmth & humidity, such as from a player's hand over time. If you really want to shellac a neck, then get the most wax free flakes you can find, use them when extremely fresh, and also use fresh alcohol, since alcohol picks up water over time. (As do the flakes) Water & wax in your liquid shellac are the enemy here.

Someone recently posted that isopropyl alcohol is the least prone to absorbing water from the air. I dunno if this is true, and I don't like the toxicity issues with iso, but it might be worth considering for such a task.

George, have you ever heard of anyone using iso for french polishing, for this particular reason?