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Pete Howlett
12-05-2011, 11:50 AM
Picking up some Cardinal lacquer from my mate Dave King today and saw a pile of Martin guitar carcasses on his workshop floor. "Oh, those," he said perfunctoraly, "problem with the finish..." I stand aghast to which he adds, "Yes Pete, everyone has problems with their finishes...."

So when it all goes wrong (as it did for me last week) just remember, even the big boys have problems too :)

Rick Turner
12-05-2011, 12:01 PM
D-35's? There is a "vintage" for such problems with Martins from the 1970s...also issues with the Bolteron binding shrinking and popping loose in the waist and around the fingerboard.

The finish companies will often change formulas trying to stay one step ahead of the EPA. Vinyl sealer is one of those products that was one thing and now is another. One of the issues is that the oils in certain woods...Western red cedar, all rosewoods, etc., have a negative effect on the polymerization of finishes, both "traditional" lacquer and modern polyesters. The results are often delamination of the finish to the wood.

Finish schedules are constantly evolving at all the factories I know of, and it's hell staying on the good side of it, much less finding better solutions. This has led me to using four different products for a standard gloss finish: 1) Epoxy pore filler/pre-sealer, 2) Urethane "adhesion promoter" aka rosewood sealer, 3) Polyester sanding sealer, 4) Polyester top coat. And this is if I do not shoot a urethane color or sunburst between steps 3 and 4.

So, yes, it's as hard on the big guys as it is on us, and how would you like to have to pay for warranty work on several hundred...or thousands of guitars?

Pete Howlett
12-05-2011, 12:45 PM
Wow Rick - that certainly is a belt and braces solution. Are you concerned about compatability? Also, you said that you achieve an ultra thin coat with this method (ofrgive me if I am misquoting). How so with so many processes? Is it just one coat with each?

Rick Turner
12-05-2011, 04:40 PM
It's thin coats...very thin with the epoxy and adhesion promoter, and then reasonably thin with the sanding sealer, then sanded dead flat, and ditto with the top coats. It doesn't amount to any more thickness than one would get with nitro, and adhesion is remarkable when the gods smile.

tonewood
12-05-2011, 05:18 PM
Have been on a job for the last month refinishing one batch of 28 teak doors,of about 300. Stripping them down to bare wood and spraying Awlgrip. Nasty stuff.But bullet proof.Same process as you are doing Rick. Just have to make sure the doors are dry and clean. Scotchbrite pad in between coats/denatured alcohol tac. 6 coats total.

Pete Howlett
12-05-2011, 10:56 PM
Oh my goodness - the repetition of that would absolutely slay me!

Rick Turner
12-06-2011, 08:52 AM
The repetition of being a cabinet maker for a number of years...drawing plans, bidding on jobs, then spending days with the panel saw and more days assembling boxes...that repetition was some of the best instruction I ever got in just getting the job done. No navel gazing, just good clean accurate work to bring it in on time and on budget.

Pete Howlett
12-06-2011, 10:22 AM
We've all done it but once you have...

ukulian
12-06-2011, 12:00 PM
and more days assembling boxes...that repetition was some of the best instruction I ever got in just getting the job done.
Agreed. Including the days when I just wanted to build a box to put the boss/forman/guv'nor in!! ;)