Official Luthiers Forum!

I have noticed that there has been far fewer questions re: finish since the KTM-9 buzz has died down.

Whats with KTM-9. After shakeout by some members, mentioned very few times.
How many are still using KTM-9, how many tried and rejected (I believe the main advocate for the finish (mike Doolin no longer uses it)?

Well, I am very interested in this subject. I went and read many of the KTM-9 threads in the archive. I am considering a catalyzed lacquer (some nitro) for hardness...but still do not know. What did Mike Doolin move onto?

I read that a lot of people prefer nitro, but is anybody using the catalyzed stuff? (for hardness).

Mike

Bob...I finished 2 guitars using KTM-9 and was pleased with the results. I would use it again if I had to spray in my shop. I have found a location where I can spray nitro so I'll be using that. IMO, nitro is still the best and I'll stay with it as long as I have a place to safely spray.

_________________
JJ
Napa, CA
http://www.DonohueGuitars.com

KTM-9 has had some hardness issues. A lot of folks were having issues with it in that regard, and so moved away to other things. More and more, there are guys popping up who spray lacquer or cat urethanes etc. that will do it for others for a reasonable cost. The last commission I did was sprayed by a local guy who once worked for Guild when they were still in Rhode Island. There is almost no substitute for the look of nitro, and if you have the ability to spray it, or have someone who will do it for you reasonably, it's still the best looking finish out there.
Well, there are some varnish products that are just as beautiful, but equally difficult to deal with.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

On my earliest builds, I sprayed KTM-9. It is a very nice looking finish
but it is softer than nitro and certainly softer than the catalyzed finishes
that all the factories are using. In my opinion, nobody except other
luthiers will notice the disadvantages of the best waterborne lacquers -
so it is great finish for hobby builders and okay for full-time luthiers.

As far as the best looking finish, in my opinion, nothing compares to a
French polish finish. I just got a guitar in from Addam Stark who does
wonderful work with nitrocellulose lacquer. I also had a guitar that I just
recently had French polished. This was the first time I have been able to
compare the two finishes side by side. I am by no means a master at the
French polish process but I do a very nice job. Lacquer really brings out
the beauty of the wood, but when you really get right down to it, the
actual finish film is very similiar to high clarity plastic.   Wheareas French
polish has the characteristic of something like high clarity amber. It is a
naturally formed resin and it just looks "organic" - that is the only way I
can describe it. Also, the feel of a shellac finish is noticeably different (I
think better) than lacquer. It is a pain to do and is much more delicate
than lacquer - but it sure is beautiful. If you are only considering a finish
based on looks, I think most people would agree that French polish is
unrivaled.

Happy New Year's everyone,
Simon

SimonF39083.0856481481

Zo mijn vriend, wat is het you'd houdt van te bespreken?


Oh wait a minute you said finish not Finnish (Finland). Sorry my mistake.

I've used KTM9 twice and one time it was a bit soft, the other I had no complaints... What was the difference? I don't know. After several weeks the hardness has not been an issue with either guitar. The shine is pretty good. I'll keep using it for a while.

Thanks Don, Simon and all,
Thanks so much. I wonder if the sale of KTM-9 by LMI is nearing an end?
I have determined that I will use f/p on top and something a little toughter for body
Question for F/Pers. Will the one day method demonstrated by Robbie O'Brien work if the shellac includes added harderners?

Bob, I've seen some beautiful guitars finished with every product imagineable.

French Polish is fantastic looking for sure. But I would be very careful. FP offers NO protection what so ever... If you're a thumb-pick wearing, slap happy player, you'll score and scratch that top in about 10 minutes. A pick guard is a must unless you're aiming for that whole Willie Nelson 'Trigger' thing.

I've seen some fantastic guitars with Nitro, Cat Polyurethane and KTM-9... I think the secret is in being patient and waiting for the product to properly cure.

_________________
I'd like to be able to prove, just for once, that money wouldn't make me happy...

[QUOTE=RCoates] Zo mijn vriend, wat is het you'd houdt van te bespreken?


Oh wait a minute you said finish not Finnish (Finland). Sorry my mistake.

[/QUOTE]

Hey...that's Dutch, not Finnish

[QUOTE=SimonF]
...As far as the best looking finish, in my opinion, nothing compares to a
French polish finish... It is a pain to do and is much more delicate
than lacquer - but it sure is beautiful. If you are only considering a finish
based on looks, I think most people would agree that French polish is
unrivaled.
[/QUOTE]
Simon has it right. A buffed out lacquer finish looks way too synthetic and "factory" for a fine handmade guitar, IMO. Some folks think the "wet look" of a high gloss finish is a thing of great beauty. However, if you have a chance to compare a good French polish job to a high gloss lacquer, there is no comparison.
The concept of durability is a slippery slope. Catalyzed urethane is durable for sure, but its toxicity should disqualify it for all but the most diligent users who have adequate protection and a good way of keeping the overspray from entering the atmosphere. Some of the OLF community are too young to remember Bhopal, India. A di-isocyanate compound leaked from a Union Carbide facility and killed over 2000 people in their sleep. Toluene di-isocyanate is the catalyst in lots of 2-part urethanes. 'Nuff said.
Lacquer can take more abuse than French polish, but Joe Sixpack isn't buying our guitars, right? Most of the folks who are paying $4-12K are experienced users and know that these guitars are different than the ones at the megacenters and take a bit more care.
Water based finishes might be good for the back and sides, but not a good thing the soundboard. I posted a question about Ceramithane, a water based finish with good brushing qualities, as I am considering this option. Oil varnishes have some good attributes, but are not as good as they used to be. The problems of witness lines, dry times, and keeping partially-filled cans fresh make oil varnishes a discipline in themselves. There may be some good ones out there, especially in the marine coatings (but again, not for the soundboard). The expense of trying a quart of this and that adds up. Jamestown Distributors has quite an inventory of marine varnishes in case someone wants to experiment.
The repairability of French polish has been much discussed as a positive attribute. A customer of took a French polished guitar of mine on an airplane and had to check it in to luggage. The flight was delayed and the black case sat on the tarmac for a number of hours baking in the Texas sun. It got so hot, the shellac bubbled in the pores. He was horrified as he thought an entire refinish was called for. After a little 320 grit sandpaper and about 1 hour of padding and polishing, the guitar was as good as new.
I am sure many of us have seen old Martins, Washburns, etc. that were finished before cellulose coatings came in. According to Mike Longworth, Martin's finish was orange shellac prior to lacquer. I have seen many of these old guitars that looked fantastic and certainly were not babied in any way. It is possible that shellac making techniques have changed over the years and what we have is not as good as what they had. (See a previous post of mine about shellac making). Handmade shellac is melted and strained through a canvas bag. It is like button lac in this regard. It could be that the solvent extraction method is not as good as the heat method. Anybody want to take this ball and run with it?
Craig Deller is a furniture conservator in the Chicago area, www.deller.com. He is using a synthetic resin in small proportion to shellac, Paraloid B72, as an addition to his French polishes. He finds it helps the build and durability. It is considered an archival medium. I might play around with this at some point. Kremer sells it already mixed up in a tube.
Finishing is a topic I have spent years working on. I sprayed lacquer for 20 years and came close to using catalyzed finishes before I came to my senses. When you consider all the aspects of finishing a guitar, from health (personal and planet), to beauty, to acoustic benefits, French polish gets my vote.

_________________
Stay with the happy people.
--Reynolds Large

fp is great finish. production even in small 1 man shop would be a long process and slow production and delivery even if good at it and getting to that point takes time. i am talking customer quality one would want out there

Thomas, I can't argue about the beauty of FP, it does have a luster that is hard to beat. I think in the classical world, FP is almost a necessity.
However, steel string players are a lot harder on their instruments, and FP won't stand up to the daily abuse without a lot of trips to the builder for finish rehab. If someone could come up with a way to make a FP guitar as durable as lacquer or others, I'd be all over it. It's the most environmentally-friendly finish out there, and it is stunningly beautiful if expertly applied. It just is not as tough as is needed on a steel string, at least from my experience.

There seems to be no ideal/perfect finish for all needs.

Except Pianolac.   

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Don,
I agree that the final FP film as we do it today is not as maintnenance free as lacquer. I believe the old timers had a way of using shellac that yielded a finish as durable as lacquer today. I have been impressed with the old Martins and Washburns that did not lead a pampered life and still look great. Cellulose finishes came in as a cost-cutting measure due to inexpensive materials and the fact that a relatively unskilled worker could apply it. I hope I can get enough guys excited about the prospect that between us we can find out if the shellac resin has changed through the years (what hasn't?) and if the old style is still available today. Or, if mixing in B72 will "make it better". I think there may be something to the heat processing and solvent extraction methods accounting for some differences in shellacs.
As for time differences between lacquer and FP: I have got it to where I spend less time on a FP than I used to do on lacquer, about 5-6 hours per guitar start to finish. The learning curve is not that great. The biggest breakthrough I had was using different style rubbers, depending on what I wanted to do. For bodying, use cheesecloth with no cover. You will build a film quickly. For final glazing, use a fine cover and very dilute shellac.
Don, you are also right that FP is essential in the classical world. Classical players are used to caring for FP and tolerate a bit of wear and dulling. With a bit of input from the builder, I believe some, cetainly not all, steel string players could see the benefits of FP as well.
Let's get a bunch of builders working on figuring out how to make shellac as durable as the old timers and we may be able to wean ourselves off the nitro habit.

_________________
Stay with the happy people.
--Reynolds Large

I thought I would chime in once again, regarding French polish. Going by
looks and feel alone, it is simply phenomenal. French polish will make
ordinary indian rosewood glow and sparkle in the sunlight.

But to be quite honest, if you aren't comparing these finishes side by side
- it is difficult to notice a big difference. I believe that lacquer is the best
finish for a high-end steel string because it is a "traditonal" finish. It is
not extremely difficult to repair and it is a very tough finish. For me, the
biggest disadvantage with the new catalyzed finishes is the difficulty of
repair. Trust me, if someone spends thousands of $$$ on one of your
guitars, they will want it fixed if they bump it badly.

I personally, don't want to feel like I have to baby a finish, which I do
when I am playing a French polish guitar. A lot of people have the same
mindset as me. I certainly don't mind trading a little loss in beauty for
what I feel is a big gain in durability.

I am going to offer both a French polish finish and a lacquer finish. I will
inform the customer of the advantages and disadvantages of both. But I
do think it is nice to give them both options. If you are building
classicals, you have to French polish to be taken seriously.

Happy New Year's,
Simon

[QUOTE=russ] [QUOTE=RCoates] Zo mijn vriend, wat is het you'd houdt van te bespreken?


Oh wait a minute you said finish not Finnish (Finland). Sorry my mistake.

[/QUOTE]

Hey...that's Dutch, not Finnish [/QUOTE]

Good eye... Bablefish didn't have a Finnish service.RCoates39083.6074768519

I use and like KTM 9. I spray and set a small exhaust fan in my basement window. Eight to ten coats works very well for me. I have been impatient in the past in getting the guitar buffed and the bridge and neck attached after five days to two weeks and have always had a stray scratch from a fingernail or something. I now wait at least 10 days to do the final buff out and then another week or two to do the neck and bridge and final set up. Any small nicks or scratches, I fill with super glue and level and polish with micro mesh.
I believe, that after the finish cures properly, it is as hard as nitro. I have not compared it to catalyzed or two part finishes.

Has anyone tried french polishing over a harder finish? That might be the best of both worlds. I saw Les Dudenbostel doing french polish over varnish on an episode of Handmade Music.

Lately I've been thinking about how a finish needs to age gracefully. I don't think a lot of these new finishes will do that. It's a little more like beat-up plastic. I've had some success bringing them back to life on very small repairs using CA glue. For larger repairs, sanding down to a very thin finish on the affected panel and then refinishing that panel works well. But it's cosmetic surgery kind of like our national obsession with youth and beauty. For many it's not okay to get old and a little wrinkled. Buyers pick up new guitars based on looks before they even play them and don't ever think about what it will be like in 50 years. Luckily some players respect and even demand a patina that only comes with continuos play on a gracefully aging surface. I don't think new finishes will ever achieve that. It's too bad because there is something personal about an old guitar that is grimey and worn here and there. I think that's a part of what makes people want to play.

With that said I'm still searching for the perfect finish. I don't think I've finished two guitars exactly the same. I've used KTM, catylized urethane, french polish, precatylized lacquer, True Oil, and varnish. They all have their disadvantanges and I hate the outgassing and smell of nitro. I'm presently using a catalyzed car clearcoat finish applied very thin so it won't affect accoustics. But oddly enough the finish I like best is from spray cans of Rustoleum acrylic lacquer I got from the local hardware store. I couldn't buff it to as high a sheen as lacquer so it has more of a french polish gloss. I used it on an early guitar before I got my spray equipment together. That guitar shows signs of aging gracefully and is still a little tougher than some. The sound of it is aging nicely also. I'd like to find the same thing that I can use in my sprayer.

If you're interested in using an archival medium I think Brian Burns, is doing some experiments with one in his french polishing. He's also experimenting with acetone as a solvent in french polishing.

Bruce Sexauer is using some acetone in his varnish to reduce the problem of witness lines and speed drying.

_________________
Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Hey Thomas,
Great points you made...
When I first started building, I wanted to go with shellac, but what had me concerned was it's inability to handle being splashed with alcohol accidently. I figured that eventually, someone would get some wine or something on a guitar, and I would get stuck fixing the finish.
Now, if there IS some way to give it that durability, I would love to move in that direction. Although honestly I'd rather have a spray version. FP is too hard on these old fingers and elbow.

Hesh,
There is tremendous evidence that shellac is the most acoustically transparent finish available. While nitro has become the "traditional" finish, it is not a superior one for that reason and also toxicity reasons as well.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

[QUOTE=Don Williams]
... someone would get some wine or something on a guitar, and I would get stuck fixing the finish.
Now, if there IS some way to give it that durability, I would love to move in that direction. Although honestly I'd rather have a spray version. FP is too hard on these old fingers and elbow.
[/QUOTE]
Don,
After a period of years, FP becomes insoluable in alcohol, which is why a lot of conservators do not like it (not reversable). As for the spray question, I believe there is a compaction of the shellac that happens by being applied under pressure during FP'ing. Sprayed shellac will not harden to the same degree padded FP will.

Hesh, I can say conclusively that FP makes a difference in classical guitars and I see no reason why it wouldn't work better on steel strings. I am finishing up my first steel string in 20 years that will have a FP on it. I'll let you know. The biggest surprise I had with the sound difference between lacquer and FP was the bass. Much bigger and deeper on a FP guitar. You'd think the trebles would benefit from a harder finish, which they do. But in the bass, the difference is dramatic. How do I know this? I had a chance to compare 2 similar guitars of mine, one lacquered and one FP.

_________________
Stay with the happy people.
--Reynolds Large

I recently had a KTM finished steel string come back to me with orange-peeling of the neck where the owner's thumb tended to rest in first position. The body seemed fine. I was told by another forum member that I had applied the finish too thickly, although I thought I was carefull to follow the Doolin schedule. I pulled the neck, stripped it down and refinished it with Tru-Oil and now everyone is happy. I have heard others complain of this product reacting to sweat.
I used the Stew-Mac water-based product on my last guitar. It sprayed and sanded wonderfully, although it is a bit soft and did leave a blue-ish cast on the EI rosewood body.
It is all a toss up. As we know even the KTM guru went over to the Dark Side.
By the way, why not brush shellac, sand and buff? How would that differ from FP?
The late-great lute builder, Bob Lundburg,scraped his tops, burnished them with nylon netting, and then applied two coats of wax as a final finish. I suspect the owners of those instruments kept their hands rather clean....

_________________
It's not the miles ahead, it's the stone in your shoe


In Markham,Virginia

Okay finish gurus, why not French polish over a couple of basecoats of lacquer? Seems the lacquer would provide the protection needed for steel strings and picks (plectrums) and the French polish as topcoats would be easy to repair. Anybody doing this?

_________________
Don Atwood
Arlington, VA

Jon, I have never had any issues with KTM-9 reacting to sweat, and this is the first I've heard that from anyone using it. The old version (KTM-4a)may have had some issues, but not the 9.

Hesh to follow up with what Thomas said, a number of years ago I built a mahogany/cedar dread that I sprayed with shellac. The sound was fantastic. I made the mistake of letting a a friend play it, who used a heavy pick and shredded thie finish on the top. I ended up spraying some ktm-4a over the shellac, and although it still sounded good, it was not the same as with just the shellac. It lost some of the clarity and edge off the sound. I am convinced that plastic finishes mute the sound to some degree, and feel that there has to be something better than plastic to finish with.
Maybe I'm wrong. I think the real issue is to get the finish as thin as you possibly can get it if you're going to use urethanes and such.
Al Carruth has stated that oil varnish that penetrate also mute the tone, and if you're going to use them, they should be applied over a sealer.

I would LOVE to have John How or other Rockhard Varnish users chime in about the use of that product, which is also a beautiful finish. I don't know how it affects the tone, if at all, and would like to hear what they think.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."