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Can anyone tell me the safest (for me and the wood) way of removing Nitro Laquer? Sanding, paint remover product, etc? I'm going to refinish with KTM.
Also does anyone you know of make a preshaped Gibson type (upside down Martin) bridge that is a little oversize ( I want more meat behind the strings) I also need, if it is already drilled and slotted to be left handed. I can drill it and slot it, but I am trying to save as much time as possible.
Thanks so much, Tim

Sory about not posting much lately, been very busy.

First question is why do you want to remove the nitro finish? On the bridge issue I don't know of a pre-made Gibson over-sized bridge, but would be easy enough to make. Lefty Martin style over sized bridges are available at lots of places.

I don't want to use a lefty Martin bridge (Gibson did theirs upside down and I want it to at least look correct for the guitar) although I may end up using a blank one, probably end up making it from scratch.

Regarding removing the finish. The guitar is a cheap Gibson dreadnaught that has many dings dents etc. and an ugly sunburst with red paint (even on the edge of the fingerboard). It belongs to my brother and he wants the cedar showing and no burst or a very subdued one. Also the original finish is in very bad shape so I need (want) to remove it and start over with a water based finish like KTM. I'm not going to spray lacquer in my dining room (no shop).

The guitar isn't an expensive piece but does sound great, should be even better without about fourteen pieces of metal in the bridge anymore.

Anybody with any ideas on safely removing the nitro?

Thanks,
tim

Tim I have used strippers (from the hardware store not across the tracks.......) to remove nitro under where a bridge was to be glued. I think that I used "Stripeeze" and it worked great.

You could try calling Gibson for a replacement bridge.

I an afraid you may have problems removing the the burst if it is stained into the wood and mot layered in the finish. Also depending on when the guitar was built there is a good chance it is not Nitro but rather cat poly or cat urethane.

Thanks Hesh.

Michael,
I believe it's nitro (surely could be mistaken though) by all the cracking and crazing.
As far as Gibsons bridges though, they are way too heavy in my opinion. There are all sorts of screws and bolts, nuts , etc for adjustments that can be done without and the new bridge will probably weigh half to a third of what it did. I have to believe in should sound better if not at least have more volume. perhaps less sustain though.

You are very welcome Tim.

A note on the heavy original bridge - depending on how stiff the top is braced sometimes a heavier bridge is a good thing. The analogy would be not unlike a 4,000 lb car needing a more powerful engine to move it. I suspect that Gibson's bracing and bridge may be optimized, in the design, to account for a heavier bridge. Perhaps not - I don't know but a lighter bridge is no guarantee of a better sounding, more responsive guitar.

I went through this whole Gibson bridge thing a while back on a repair. Had to make a slightly oversized Brazilian bridge and wasted more time looking around for one than I should have.
When I finally just sat down and made the thing, it took almost no time at all. Wish I would
have just started there.
I agree with Hesh on this, the mass of that bridge did wonders for this Gibson, it's really what it needed for whatever reason. I made the guitar come alive.

As far as strippers, the main issue is just the bindings, if they are ivoroid or a celluloid base, the stripper can be deadly for them. If I have to remove finish (and I almost never do) I bring the stripper up the the taped off bindings and do them by hand with a scraper. Even the solvents in the lacquer can cause problems so that's why it's so good to avoid refinishes. You will be using something other than Nitro so that will help. Just be careful with the stripper on anything
"plastic", wood bindings are no problem of course.

Someone with a good CNC machine could do well producing Gibson bridges, I think there's a market if you just don't have time to make one...

Best
Bruce

_________________
Bruce Herrmann
"What lies behind us and what lies before us are tiny matters compared to what lies within us."

Thank you all,
The bindings are plastic and that has worried me. I may just end up sanding. Maybe I'll get lucky and not have to go all the way to wood,..........nah, the dents are too deep. We'll see. Although masking the binding first,.... I like that idea. I think I'll try that first in an area that can be repaired without being noticed.

As far as the bridge goes I just can't imagine all those bolts and nuts and screws and springs can do much but reduce the responsiveness. If it ends up needing more weight that will be an easy thing to do.

tim

Caution is advised Tim....most stripping agents (StrypEeze. Zip Strip etc.) contain Methylene Chloride, exposure to which can constrict blood vessels and can cause heart attacks in those who are prone to that type of problem.
Safer are the Citrus based materials such as "Citrus Strip"
they also may be better in terms of the plastics problem that Bruce mentions above.
Whatever you choose, work in an open well ventilated area and use a respirator.

David LaPlante is correct about the fumes! Do it outside and with the proper organic absorbing filters on a respirator if using any kind of organic solvent. Even the citrus can affect you.

On the dented finish..is the wood compressed in the dents or are the fibers of the wood crushed or torn? I have not tried it but have read that some finish dents can be brought back somewhat with locallized steam. I.e. a drop of distilled wated on the dent and an iron or other hot heat source applied. Don't try this unless someone else who has chimes in and gives their opinion!

_________________
Steve Walden
Aspiring Builder,
Bartlesville, OK

If this is truely a nitro finish, you can buff away most of the crazing with a buffing wheel and then youa re still original. One company that sells vintage guitars does this as a routine. It will look as good as new with just a good but heavy buffing.

as far as the CNC and gibson bridges, if someone has a digitized NC or Gcode for them, I'll be glad to make some.

_________________
Reguards,

Ken H

I saw this stuff on "cool tools" on DIY tonight.. may be something that can come in handy to remove poly finishes?? It doesnt specifically say so, but it may also work on nitro lacquer as well... worth investigating I guess

SOY GEL

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Reguards,

Ken H

I wrote to the soy gel people and asked about nitro. Here is the response I got:


On 2/8/08 12:39 AM, "Ken Hodges" <ken@hodgesguitars.com> wrote:Ken Hodges


Does the soy gel work on nitrocellulose lacquer? What affect does it have on the wood after use?


Ken,
As far as I know it will work on nitrocellulose lacquer. My advice would be to try as small test area first. It will not harm the wood.


Joyce Laskowski
Customer Service Rep
Franmar Chemical
800-538-5069

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Reguards,

Ken H

Thanks again all,
The problem is he doesn't want the original finish and it is poorly (tackily) done so I've got to start over.

tim

Ken, it sounds like Joyce hasn't the foggiest clue if this product will work on Nitro Lac or not. She's asking you to test it.

_________________
"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

I think you're right Chuck. I know there are some citrus based removers too. I wonder if anyone has tried them?