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I have been out of the guitar scene for 20 years. So my base of knowledge does not include anything on the current PRS guitars.

I have heard salesman refer to the finish as being nearly bullet proof. Saying "since the finish will never damge or chip or degrade that it is theoretically the last guitar that you will ever need to buy"

With all this big talk about the strength and durability of the PRS finish I'd like to know more about it. The PRS site did not seem to offer much info. So I was hoping that someone here might know more about it and be able to offer some insight.

It's basically automotive clearcoat (acrylic urethane if I remember right)

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http://www.PeakeGuitars.com

Google "PRS finish"

Result 3, from the PRS site:

http://www.prsguitars.com/csc/faq.html

"What kind of finish does PRS use?

We finish our instruments with a polyester basecoat and acrylic urethane topcoat. We feel acrylic urethane looks and feels the closest to the old nitro-cellulose finishes but without the finish checking."

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Thank you Bob and Parser

Has anyone else worked with a polyester basecoat and acrylic urethane topcoat? I'm just wondering how difficult it is to apply. Or I should say if it more difficult to work with then Nitro? I have not got into finishing yet so I have not done much research on it.

That is what I use. It is much more forgiving for the first time finisher, as in normal drying temps, you are looking at 8-16 hours cure. Which allows for mistakes to be corrected very quickly. As far as bulletproof...well that is not exactly true. It scratches and chips and peels just like nitro, but is a little softer, so it is not so prone to chip - rather dent.

I use production clear from autobody masters ($33.00 for a quart and pint of catalyst) put over a west systems pore filler. I am still looking for a good polyester base / pore filler, but have not identified one yet...

You can check out some of my recent postings to show you an example of the finish I get (using a Preval spray system outside)

Stephen

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www.ziegenfussguitars.com

I read in an old Dupont Refinisher news that they use ChromaPremier base color and 4500s Urethane clear.
I would imagine you can easily repair it the same way you would doing an automotive refinish repair.
Hope that helps
Cheers

Looked around a bit and came up with more info for you.
Click the link.

http://www.pc.dupont.com/dpc/en/US/html ... elease.pdf

It depends on what kind of polyester your talking about. there are many.
most polyester finishes are DEADLY to handle or spray. And yes, most of them are near indestructible, which makes them ideal for sealers/bases.
I have used a shirwin williams conversion varnish, and its polyester based. Its VERY hazardous, and is a pain to sand, VERY touchy about mixtures or else it doesnt spray well at all.

Auto clearcoats are the best in my opinion. most are meant for heavy use, and offer the best protection. But again, all 2k urethenes are deadly.

Polyester is hugely more difficult and has the shortest pot life and shelf life (once cobalt is added). Auto clearcoat is not too bad to mix and spray, but the most expensive of the three. Lacquer is the cheapest and easiest, but takes the longest to cure and is the least durable. Lots of builders love it though and it's a great place to start.

Can you post a pic of it? I used to do high gloss touch up on very high $$ pianos! I did refuse to work on a 11ft Bosendorfer though! I also use a lot of the automotive clear coat in my regular product finishing.

Mike

Yes, The majority of prs guitars use acrylic urethane - I worked there in 1986 when they were in Annapolis Md. - at that time the product was Dupont DAU-82 acrylic urethane - an automotive clear coat - that was all they used then - the dye for the tops were mostly leather dye from tandy leather (yes, it's true) and the toners for the transparent red backs and sunburst shadings I'm pretty sure was an acrylic lacquer. The process back then was to stain the top, spray a wash coat,(acting as a sealer) on entire guitar, scuff w/ scotch brite type pad, spray 3 wet coats, sand 240 grit to level, then apply toner color to the back and sunburst (if called for) then clean up any overspray, make sure all taped lines("binding") were clean, then 3 wet coats of clear, sand 1200 and buff. There was no pore filler used and on some colors (especially emerald green) would fade if a store owner displayed the guitar in a window exposed to sunlight. At that time guitars were coming back where the finish sunk into the pores of the mahogany because no pore filler was used - Obviously they have improved the process since, but I thought you might find this interesting.

I left PRS just before the amps were in production - I knew of Pritchard, but I don't think I ever met him. I think there was a prototype amp or two around, but I don't really remember for sure. They had just started production of the 4 and 5 string basses (early 4 & 5 strings had the same width necks) and had just introduced the guitars with the weird metallic finish and crackle finish - I think those were the first to have the wide thin neck, if I remember correctly. I originally worked for KT guitars (Koontz Thurston guitars) in Baltimore for a short period, when they folded I went to PRS.

3 top coats?!! Paul wasn't kidding when he said the paint was thin. Those must have been a nightmare to sand and buff.

What was the organization end of things like back then? They were in a pretty heavy growth phase weren't they?

Yeah it was a really excitng time - things were really taking off. You could feel that it was something great - everyone took such pride in their work - really cool. I think there were around 20 employees at that time - 3 coats of urethane was about equal to 6-7 nito lacquer. It also sanded fairly easy - being harder than lacquer it was a little more forgiving if you were a little heavy handed w/ the scuff sand. Having said that - the trade off was if you did burn through the finish, it was a little trickier to touch up than lacquer. Sometimes you'd get a little crazing around a touchup - The real headache was that there was no pore filler used at that time - sometimes you'd burn a finish trying to scuff the surface level on the mahogany parts - it was actually pretty rare to burn through the top coats, though.

Cool, I'm sure we know a few of the same folks (including Paul of course). Joe Knaggs (who has started his own guitar company), Geoff Jacobson, Larry Urie, etc.. I worked there for about 3 and a half years starting about 5 years ago. The company had certainly matured by that point - there were about 200 people when I started and about 250 by the time I left. I worked for the R&D department when I was there..it was a pretty cool time to be there as they were (and still are) trying to figure out how to function as a larger company. I left right before they moved into the new expanded factory....but not before getting addicted to all this stuff...! It was very cool being around such nice work.

Trev

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