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Latest Activity: May 16
Started by Greg Nelson. Last reply by Luis Motta da Silva May 13.
Started by Luis Motta da Silva. Last reply by Michael S. Jackson May 6.
Started by Luis Motta da Silva. Last reply by Luis Motta da Silva May 5.
New pics from my ongoing projects!
"Lily" solid body guitar:
Renew of 1980 bass pickguard and electronics:
I have a small body Japanese Daion L-999 which back inner side (but not the sides) is sealed. It sounds very good, but I can't say if it's due to the treatment..
Sorry about the link. Maybe this will work.
Accidentally doubled up on the "http"
I have thought about “sealing” the inside of an instrument but shied away so far because, in part, no historical “great” guitar or luthier employed this (to my knowledge). I did run across this Taran Guitars on YouTube. This guy French Polishes the inside (at least the backs) of his instruments. He doesn’t mention it on his site, but visually it appears to be the case.
I once had a very small bodied Guild that was oil finished and made of Honduras mahogany stem to stern (body, neck, soundboard, bracing) with an ebony fingerboard and bridge. It had no bindings/purflings, headstock veneer, or rosette. It was a nylon stringed instrument and I suspect a relatively short scale for a “classical”, (some things escape my memory). This was in the early 60s and it was a really sweet instrument. I have often thought of trying to re-create this from memory. I have a nice piece of Sapele (I believe it made the move) that could go to this project. The point of that tangent was that maybe an oil finish (linseed/beeswax) may serve to protect the interior with minimal tonal impact. I would still stay away from the soundboard (maybe).
Interesting discussion! What shall I say?
1) I never coated the inside of the instruments I make, nor do I have one that is coated inside. So, there's nothing I can asseverate based in experience.
2) I happen to know a guy, near Lisbon, that makes hi-class instruments, for worl-known guitarists (Pat Metheny, to name one). He continues a 3-generation tradition of guitar makers. Well, he is said to have tried inside coating, and have abandoned that.
3) Despite that, I can only imagine that coating the sides with a thin layer of shellac will have some good effect on the risk of cracks. That could be done with a soft brush, or even a "doll" - if you take care not to coat the parts where the linings will be glued. I admit that the effect of that on the instrument's tone will be minimum - if any - because sides don't have a relevant effect on the instruments acoustics. Coating the back could be different and, as Jay Lichty says, it can have an effect in sound projection. But, as I said, I can only speculate - I never tried it.
4) I do believe that instruments in the white sound softer, that is, they sound more like wood. After varnishing, they get a brighter tone.
5) I'll follow this debate. I've read really interesting things! Thank you all!
I use a 2" throw away foam brush. I glue the back to the sides first and brush the back and sides before gluing on the top.... I never apply the shellac to the underside of the top.
seems to me it that coating the inside of the backs and sides is a good idea to help against cracks and rapid changes... however the top being the actual soundboard you may not want to inhibit the movement ... this might produce the best of both worlds..?
A ?...how do you coat the inside of an acoustic guitar??? I have to assume it's before you glue on the top? Just curious!
For what it is worth I started coating the inside back and sides of my guitars and ukuleles about 10 instruments ago. I started doing this at first because, in my opinion, it should help stabilize the more (delicate) crack prone woods like Brazilian rosewood and Zircote. I was really pleased with how it looked as well as the affect I perceived to the sound and projection. I only use well-seasoned wood and keep my entire rather small shop as close to 45% humidity as I can but I did still have an issue with some BRW so wanted a little extra “insurance” against future issues. Additionally as an experiment I built a guitar out of a back and side set that really had limited tap tone to see what kind of tone I could create. As part of my strategy I did three coats of shellac on the inside of the back and sides. The resulting build was quite astonishing and the tone, projection and sustain well surpassed my expectations. It is one of my favorite guitars now. Thanks to Jud for bringing this topic up because I am also very interested in the experience and opinions of you all.
This subject comes up on occasion and I don't think there is a right or wrong answer. Tradition is to not finish the interior but many fine instruments do have at least a wash coat inside.
Finishing does change the tone but the question of "better or worse" is subjective. I don't think you can claim sonic improvement or degradation. To be honest I like the sound of instruments in the white and wold prefer no finish at all but the down sides are huge.
The argument about sealing the woods to protect them against rapid changes due to RH is a good one. A sealed finish will slow the movement of moisture in and out of the wood compared to no finish. Will it prevent a crack? Too many other variables to make an definitive answer for that.
In the end people don't like surprises. Finishing the interior is "different" so there will be resistance to it by many. A few have embraced it. Vive la difference!
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