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Thanks, Michael: somebody gets it...

Several years ago I had a student who was a study in ADHD: he wanted to do all sorts of fancy stuff, but couldn't seem to stick with it long enough to get it right. When he made mistakes they never got fixed right, so the guitar ended up pretty rough around the edges in some ways. He was, however, very good with lacquer, having made a living painting motorcycles at one point. He took the guitar home, got himself a case of rattle cans from Stew-Mac, and put on the best lacquer job I've ever seen. Up to that point I used to think that you couldn't hide anything under a clear finish: now I'm not so sure. The mistakes were still there, of course, if you looked for them, but very few people ever got past that surface.

To me, the look of the violin is the proper 'craft' standard: asymmetry, a few tool marks, and a scraped rather than sanded surface, all show the hand of the maker. It's NOT 'sloppy': I'd love to make 'mistakes' that were as good as Strad's, but it's not the totally uniform 'factory' look either. A fine violin is a work of art; Martin and Taylor are factory productions. Why in the world have we allowed ourselves to be tied to the factory standard?

Of course, in the highest craft traditions a fine finish counts for a lot: Strad is still known for his varnish, after all. But the best evidence is that he didn't rub them out, and was not overly concerned with shrinkage either. The guitars I saw in Spain in the early '70s, when French polish was still the norm, were not totally filled: they were only just starting to fall into that trap then. Shrinkage that left the grain, and the structure of the rosette, plainly visible, was considered a sign that the finish was not so thick as to impede the sound. In some cases they'd leave the shops pretty 'dry', and get the polish built up over the years as they came in for adjustments and repairs. Even the pianos I've seen that dated from before the introduction of nitro didn't have 'piano' finishes as we think of them.

Several years ago there was an exhibit of guitars as works of art in Boston. It was pretty easy to see when Martin switched over to nitro: the ones made just after the change had finishes that were in much worse shape than the ones from before the switch. That's not that long ago. Why would you want to use a finish that doesn't hold up as long as your guitar? Or, if you like that look on a new instrument, why not just accept the fact that it will need to be renewed every once in a while? This business of treating a modern mass produced guitar with a nitro finish as if it was a 300 year old varnished violin is absurd: nitro is an industrial coating, Strad's varnish was part of the artistic intent.

Sorry for the rant. I understand that 'slick' is the accepted standard for guitars these days, and put in the work to meet it as best I can, given the limitations of the finish, but it ticks me off. Factories live by that sort of unimaginative 'flawlessness', but it's a luxury, and a very expensive one, for a hand craftsman. By holding us to their standards, and not just in finish, they distract the buying public from the things that we can do that they can't. We ought to be trying to get them to play by OUR rules.

Prreach it Al! Can I get a witness?

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Pat

Amen!

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I would just like to point out a few things....First, shellac and varnish were the industrial finishes of their day.The old timers used them because that's what there was and until something better came along.....well nitro was the first of those something betters. That has been supplanted by polyester based coatings like amino alkyd conversion varnishes, pure polyester in a UV cured form And many other acrylics and polymers like urethanes etc..

Second, they call it sanding sealer for a reason. It is generally meant to be sanded prior to the top coat application. Sometimes the coating needs that mechanical anchor, nitro doesn't readily melt into vinyl all that well. The vinyl sealer provides a bit of float between the wood and the acrylics as well as sealing the wood and providing a base for the coating. The float is needed to help prevent cracking and crazing in modified lacquers that do not expand and contract as well so they can keep pace with movements in the wood.

Third, Inter-coat sanding (Beyond sanding the sealer or leveling shaders) is really only useful if you want an off the gun finish. If you are going to level sand and buff at the end it is a waste of time. You will never save all the time on the final level sand that you put into the sanding and then cleaning in between coats so you will spend more time doing this than is actually needed. Then there is the cost of the extra abrasives and the extra material you always wind up putting down because you are sanding 30% of each coat back off rather than 15% of the total film at the end. And in the end there is no visual or functional difference if you do all your sanding at the end. It is a common problem in woodworking that people start sanding too early, sand way too often and sand too much.

Well that's my two cents for the day, now I'm broke again.

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Brian

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

https://www.howardguitarsdelaware.com/

I spray a few coats then sand level with 220, spray a few more, sand level with 1500.

If I waited until the end and sanded with 1500 it would take a LOT longer than sanding once with 220 and once with 1500.

If I waited until the end and sanded with 220 then 1500 I would likely sand through in spots.

That's my argument for intercoat sanding.

The rest doesn't bother me, I like shiny hard finishes as well, as long as they're thin enough. My customers don't mind the reedy look that my soundboard gets because I've explained to them that the sound they're hearing is partially due to the thin finish, and they "get" it and explain it to their friends when they ask.

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Old growth, shmold growth!

My sanding schedule for buff out stats at 400 as well. Then I use every grit up through 1200 and then buff. This really does not change much with sanding between coats.like Filippo said, maybe start at 600. So I maybe save 10 minutes there but spent an hour or more sanding between coats and cleaning the surface for the next coat.

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Brian

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

https://www.howardguitarsdelaware.com/

I find it quick and easy to sand the first time with 220. The next round of spraying levels out all the scratches, and if I get a good flow leaves it practically ready to buff. So I start with 1500 and that's all I need and it doesn't take super long.

My schedule is based on the fact that I used to use rattle cans (15 years ago) which didn't build very fast, and so I would sand through frequently even if I started at 600 grit, so I started to just go for the 1500.

I started doing my first level sanding with 220 after watching Bob Benedetto's archtop video.

Finishing is not my strong point, but why the sarcasm?

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Old growth, shmold growth!

Great thread.

So Todd, you're shooting un-thinned. Four coats, sand, four more on top, five on back/sides.

Filippo, you're shooting six straight. Also un-thinned, right?

I love this forum! The articles complaining about customer desire for flawless shiny guitars made me feel less alone in the world.
I am an amatuer repairman, but my friends and I play our guitars a lot at rough parties. What I have learned how to do in finishing is this: I can take an old nitro guitar that has been to five hundred rough parties plus been horribly broken and repaired wrong, and rescue the situation so that it plays right and only looks like an old guitar that has been to five hundred parties. We all love that look. It's easy to get with nitro and transparent dyes. I love the deep look of a colored dye over a slightly different color layer. Looks like beautiful old guitar to me.
I've never tried, but I suspect that it would be much harder to do this kind of finish repair with modern cross-linked finishes. I've used a lot of good superglue in model airplanes but not much on guitars. I would be happy to hear from someone that repairing modern finishes is not that hard. I'm talking about stuff like taking a broken headstock fixed with wierd color wood splints, ugly amateur repairs, and making them so it takes a real hard look to see where it was broken, while leaving the guitar looking loved and used hard.

I spray my finishes with a brush.


Sent from my iPhone using Tapatalk 2

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http://www.CostaGuitars.com
PMoMC

What size fluid nozzle and air cap on that brush?

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jw ( o)===:::

It's a 2 inch nozzle with several thousand tips. It leaves a rough finish but I don't mind a bit of sanding.


Sent from my iPhone using Tapatalk 2

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http://www.CostaGuitars.com
PMoMC

That's a Super High Volume medium pressure setup I believe.

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jw ( o)===:::

Cool. Thanks, Todd. I'm spraying Cardinal, but I'm going to try this on the guitar I'll be finishing in the next week or two.

Spraying finishes with a brush has definite advantages. It's cheap. Don't take up much room. Zero maintenance. If you break or lose one of those tips it doesn't really matter. You can shellac your fingernails with one. I'm sure there are numerous other advantages.

Simple dings and chips get the CA fill. You can pad it onto larger areas. But for a headstock like you mention I usually will refinish the neck with a two part urethane. This is almost mandatory if you need any color other than clear for the repair.

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Brian

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

https://www.howardguitarsdelaware.com/

That is correct. That must be why your finishes are so good!

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http://www.CostaGuitars.com
PMoMC