Nitrocellulose and guitar tone

[MartyGrass]

Someone I know is completing his Heritage build of an archtop this week. The woods are particularly nice, and he supplied them to Heritage.

 

They are putting two extra layers of clear coat on the guitar to bring out the 3D effects of the wood. Here is part of an email my friend sent me that dealt with the question as to whether extra nitro would be a bad idea. I thought this might be of interest.

 

 

 

 

 

 

When I asked Jim if the additional coatings of lacquer would have a restrictive effect on the tone board, he said . . . "no . . . not with the nitro cellulose lacquer we use." He indicated that companies like Gibson who wanted to speed up dry time for production purposes "had their suppliers screw around with the formulation" adding plasticizers for enhanced drying times and lesser potential for finish checking due to extreme temperature changes. A too thick coating of the Gibson, or the Fender/Guild formulation would indeed be detrimental to the top . . . (according to Jim).

 

[DetroitBlues]

Wow, learn something new every day....

[Gitfiddler]

Is that the norm for all Heritage archtops?

[SouthpawGuy]

I seem to remember something about a particular Heritage dealer ordering guitars with less coats of nitro to improve the tone, or similar.

 

Could be wrong though, it might have been more coats

[MartyGrass]

Is that the norm for all Heritage archtops?

 

 

It's not the norm. Apparently Floyd, who had been finishing guitars for 50+ years but recently passed, would put on extra layers of nitro sometimes if it would bring out a 3D effect in highly figured wood. I believe he did this on my blonde Roy Clark I recently sold.

 

Patrick and Dave now do finishes at Heritage.

 

Here is more from the email I received.

 

 

Marv went upstairs and talked to Dave in the finishing room. It appeared that Dave took it upon himself to apply an extra two coats ( two more than normally used) of clear. He told Marv, that he wanted to really show some depth in the finish to create as much of a 3D effect as possible, on what he considers to be the finest wood packages to come out of Heritage since he's been working there. He (Dave) consulted with Patrick before adding the extra coats and Patrick's response was . . . "that's what Floyd would have done".

[MartyGrass]

I seem to remember something about a particular Heritage dealer ordering guitars with less coats of nitro to improve the tone, or similar.

 

Could be wrong though, it might have been more coats

 

 

Jay Wolfe did this. I believe his reasoning is that it would allow the soundboard to vibrate more freely.

 

We venture into the land of opinion here. I can't imagine that the number of nitro layers is even reasonable to consider in a guitar with mounted pickups, which most of Heritage guitars have. But it might make a difference in an archtop or flattop without hardware on the soundboard.

 

On the one hand, nitro is very thin. Anyone who has a spruce top that's more than a couple of years old will note that the grain of the wood creates grooves in the nitro, evidence that nitro acts more like a semi-solid than a static protective coat and that it is sheer. On the other hand, It does add mass to the top and could dampen the vibration excursions.

 

There is a benefit in more lacquer from an aesthetic perspective.

 

Personally, if I had a guitar that is a real showpiece, I'd like the extra lacquer. Otherwise I wouldn't bother. The notion of reducing the number of nitro coats below the norm makes me nervous.

 

Here's the Roy Clark that got the extra nitro on it. The 3D effect is much more apparent in person.

 

[bolero]

has anyone ever built an archtop with only a rubbed finish? you think that would have the least amount of dampening on the wood vibrations

 

although you could also argue that a stiffer finish could enhance the vibration qualities of the top? any acoustic engineers here?

 

 

myself I prefer nitro over poly: for breathability, plus i like the aging effect as it takes on the woodgrain texture over time

 

....could I hear a difference between a pure nitro vs nitro with added plasticizers? I'm not sure but the purist/traditionalist in me would take nitro given the choice.

 

especially over the 1/4" thick shells that a lot of poly guitars get

 

 

otherwise I'm inclined to take the advice of some guys who have been handbuilding guitars for over half a century

[SouthpawGuy]

1/4" thick shells ? Shirley you're exaggerating ?

[Spectrum13]

 

 

 

 

 

otherwise I'm inclined to take the advice of some guys who have been handbuilding guitars for over half a century

That... or having over 10,000 posts on the gear page.

[Blunote]

has anyone ever built an archtop with only a rubbed finish? you think that would have the least amount of dampening on the wood vibrations

 

although you could also argue that a stiffer finish could enhance the vibration qualities of the top? any acoustic engineers here?

 

 

myself I prefer nitro over poly: for breathability, plus i like the aging effect as it takes on the woodgrain texture over time

 

....could I hear a difference between a pure nitro vs nitro with added plasticizers? I'm not sure but the purist/traditionalist in me would take nitro given the choice.

 

especially over the 1/4" thick shells that a lot of poly guitars get

 

 

otherwise I'm inclined to take the advice of some guys who have been handbuilding guitars for over half a century

I favor nitrocellulose for two reasons: First, that's the tradition and I appreciate the mojo (imagined, or not). Second, it's easily repairable; new nitro lacquer can be applied over old without any problem.

[Steiner]

1/4" thick shells ? Shirley you're exaggerating ?

 

I never exaggerate. And don't call me Shirley...

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[bolero]

haha, nice!!

 

 

here's an example

 

[SteveHoffman]

Yikes.

[SofaPlayer]

myself I prefer nitro over poly: for breathability, plus i like the aging effect as it takes on the woodgrain texture over time

 

....could I hear a difference between a pure nitro vs nitro with added plasticizers? I'm not sure but the purist/traditionalist in me would take nitro given the choice.

 

especially over the 1/4" thick shells that a lot of poly guitars get

 

 

otherwise I'm inclined to take the advice of some guys who have been handbuilding guitars for over half a century

 

 

Yikes.

 

Twice +1

 

Interesting topic. I didn't know that additional layers bring out the 3D effect better. So I guess my Guild T-500 has quite a few extra layers. Still very happy how it resonates, I doubt that I'd hear the difference to fewer layers. That said, I prefer the traditional nitrocellulose formula without the plasticizers. I don't mind at all to see my guitars age gracefully, quite the contrary.

 

 

 

[hinesarchtop]

This is a tough one Mark. On any guitar I build I want the finish as thin as possible whether it's an acoustic or electric instrument. Nitro coats are very thin, so 2 additional coats may not make a notable difference in tone, but if your rule of thumb as a builder is that everything matters then go thin.

 

When stringing up and playing an electric before the finish is applied, and then after spraying, you can here an obvious difference.

Even more so with an archtop or flattop.

 

Depending on the porosity of the Maple or Mahogany you may end up spraying more coats anyway, and also may sand more off before polishing, so two additional coats may end up being negligible thickness wise anyway.

[SouthpawGuy]

 

 

 

Twice +1

 

Interesting topic. I didn't know that additional layers bring out the 3D effect better. So I guess my Guild T-500 has quite a few extra layers. Still very happy how it resonates, I doubt that I'd hear the difference to fewer layers. That said, I prefer the traditional nitrocellulose formula without the plasticizers. I don't mind at all to see my guitars age gracefully, quite the contrary.

 

G1.JPG

 

G2.JPG

 

G3.JPG

 

 

 

 

Awesome wood in that one !

.

[SouthpawGuy]

 

I never exaggerate. And don't call me Shirley...

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

You got that right

 

http://www.youtube.com/watch?v=0A5t5_O8hdA

[SouthpawGuy]

 

 

Jay Wolfe did this. I believe his reasoning is that it would allow the soundboard to vibrate more freely.

 

We venture into the land of opinion here. I can't imagine that the number of nitro layers is even reasonable to consider in a guitar with mounted pickups, which most of Heritage guitars have. But it might make a difference in an archtop or flattop without hardware on the soundboard.

 

On the one hand, nitro is very thin. Anyone who has a spruce top that's more than a couple of years old will note that the grain of the wood creates grooves in the nitro, evidence that nitro acts more like a semi-solid than a static protective coat and that it is sheer. On the other hand, It does add mass to the top and could dampen the vibration excursions.

 

There is a benefit in more lacquer from an aesthetic perspective.

 

Personally, if I had a guitar that is a real showpiece, I'd like the extra lacquer. Otherwise I wouldn't bother. The notion of reducing the number of nitro coats below the norm makes me nervous.

 

Here's the Roy Clark that got the extra nitro on it. The 3D effect is much more apparent in person.

 

 

On a solid body electric I'm not sure if two or four coats of finish would make a difference. On a semi or fully hollow guitar yes, I'd be inclined to believe that less is more.

[SouthpawGuy]

haha, nice!!

 

 

here's an example

 

 

What guitar is that ?

[H]

 

What guitar is that ?

A broken one

[Steiner]

 

What guitar is that ?

 

The owner's name is Nick. He's a flake...

[SouthpawGuy]

The owner's name is Nick. He's a flake...

 

Nick Cadbury ? Hadn't heard of him

[HANGAR18]

I wonder if additional gloss nitro can be added to the top of an existing guitar.

But then I would also wonder if there would be a conflict between the old nitro and the new nitro on top of it.

[TalismanRich]

I wonder if additional gloss nitro can be added to the top of an existing guitar.

But then I would also wonder if there would be a conflict between the old nitro and the new nitro on top of it.

 

You can easily respray nitro. The solvent used dissolves the top layer slightly and the whole thing bonds together easily. That's one of the things that makes nitro a good finish for instruments being repaired. Poly sprays and UV coatings don't work the same way and you could have a problem with "intercoat adhesion".

[yoslate]

 

I have a Fender '52 Tele reissue. It had a poly finish nearly this thick. I removed all of it by "popping it off." All of it! Carefully pushed the edge of a chisel under the lip. It flew off. Still finding shards in my shop. Never touched it with sandpaper until it was all gone. Followed with a light sanding, and a stain to even the finish and bring the grain up, just a little. Then hand rubbed a pastewax into it. There was a noticeable "opening up" of the guitar, after the removal of the straightjacket.