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Hello, I would like to remove a fingerboard using a heating blanket. Has anybody here have experience with it? What is the procedure you followed? It seems pretty straightforward but I would like to check with you. Thanks

Yes, the guitar is in playing condition. It is a classical guitar with spanish neck. I guess the luthier, being a traditionalist, used hot hide glue...

I just did three of these. I use a heat lamp and clothes iron, but a heating blanket will work fine.If the guitar has a thick finish, carefully scribe through it along the fingerboard seam Protect the top from heat with a few layers of cardboard topped with foil. Keep the fingerboard damp as you heat it, especially the part attached to the top. If it dries out and shrinks before the glue gets weak, it can crack the top. Use a cake decorator's spatula or a similar tool, working in from each side on the top once the fingerboard is good and hot. Don't heat the tool itself, or you will damage the finish. It takes some force to separate the joint, but pay attention to the feel of the tool. You should be able to tell if you're pulling up wood fibers, rather than parting the glue line. If it's a hide glue joint, use a pipette to put a little water into the joint as soon as you get a little of it open. Be patient. When you have the finger board separated from the top, prop the joint open at the sound hole with a thin scrap of wood, and start working your way towards the nut. Keep adding a little water to the joint, and give it time to weaken the glue. If you're careful, and you're lucky, you should be able to put on a new finger board with no trace that work was done. You can make some small corrections to the neck angle when you glue on the new board--just put a little tension in the desired direction. When the glue dries, it will hold the new alignment. Be aware of the neck angle even if you don't want to change it. The weight of the clamps can make a large change if not supported.

I have also done a few, using a heat blanket, using Eric's excellently described method as above.
I started separating after about 10 minutes at 300 degrees with the heat blanket on the bench, (protected) guitar on top.
The spatula or palette knife will tell you if it is ready.
I have used dental floss to get the removal started with good effect.

Be careful with the water though... water/steam can damage finish just as much as spatula scratching the finish. Use just enough to keep the glue line moist. Most finish damage can be repaired, and it's made easier with the fingerboard out of the way. Polyester/urethane finish is the easiest to keep from damage but they are also impossible to repair without a trace.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

many thanks for the nice reply. Enrico

The advice above is all good. You should clamp a caul on the top of the heating blanket, sandwiching the heating blanket between the fretboard and the caul . I use 1/4" thick wooden caul for the full length of the fretboard. In addition to holding the heating blanket against the fretboard for better heat transfer, the caul is approximately the same thickness as the fretboard, so I know that the temperature on the outside of this board approximates the temperature of the fretboard at the glue line.

Since I don't have an adequate surface mount thermometer, I watch it carefully with my eyes and nose, and take it to the temp just before it scorches. Be careful with inlays if they are not pearl.

James

Especially if it's celluloid inlays... if you want to know why take a lighter to a Fender pick.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com