Cold bridge removal, chisel style..?

[Andrew]

Has anyone round here used this method for removing bridges much? I'm interested because I have a guitar (my dad's 73 Fender F 15, nothing too special but I like it alot) with dark stain/finish on a lighter coloured hardwood (not sure what) bridge, which is beginning to lift at the bottom. The stain has taken on a nice patina with just the right amount of wear at some of the edges and Id much rather not disturb it with heat as Ive seen happen before. So Im considering the chisel technique as a possibility.
Also, it may be important to know that this has one of those goofy adjustable saddles 'inlaid' in the bridge (it actually sits right on the top, captured by the bridge). Im probably going to work something out to convert it to the proper saddle style. Got nothin but time with this one and Ive got a couple beaters to practise whackin at, too. Lee Valley sells some cranked neck chisels that look pretty good for the job, if I deem this to be the appropriate method.

[Frank Ford]

Well, do let us know how it goes.  I've taken off lots of bridges without heating, but I use a sharpened putty knife:

 

http://www.frets.com/FretsPages/Luthier/Tools/JointKnife/jointknife...

 

Never tried the "mallet-and-chisel" technique myself - just chicken, I guess. . .

[Andrew]

Ah i hadnt considered the putty knife. Figured you would need to use a mallet to shock the glue joint to break it. How do you go about it with your joint knife, Frank? Just keep working your way around the bridge a little at a time til she's free?

It should also be noted that this bridge is almost certainly glued straight onto the finish, you can see the finish there under the adjustable saddle.

[Matt Haugen]

Just wanted to chime in on this. I have found a few frosting spreaders at thrift stores. They are amazing for this sort of job. I have come across some that need thinning, but the ones I have purchased have been perfect from the get go. If anyone happens to think of checking into them, I promise you are doing yourself a huge favor.

[Mark A. Kane]

Please video the proceedings and post the results. ;)

[Andrew]

Dunno if I could manage video but Ill certainly take pics when I get to this (the customer doesnt pay very well).

[Ned Knepp]

If any of the glue is holding like it should, I think that whacking it will probably break the wood before it breaks the glue joint. In my opinion, you would be gambling that all of the glue has failed and none of it is working properly. 

I use the same method that Frank uses but my blade has been ground round and thin plus I heat the edge with a Bunsen burner to cut through the glue. Thin card stock can be used as a shield for the finish but not heating too much is important. The blade doesn't need to be glowing hot, just hot enough to melt the glue. I've found that it's better to keep heating the blade every few seconds than it is to try to get it really hot so it will not cool below working temp so quickly. I like to work from both directions to make sure I'm not going to submarine into the grain. Sometimes the run out in the top grain is toward the neck on one half and toward the tail block on the other. Maybe  that's another reason to not knock the bridge off..  On the other hand, a video does sound like fun. 

[Andrew]

Maybe I can rig up my IPad somehow to get the right angle for the vid and use one of the beaters for giggles and to see what happens :p. Ive heard of this working cleanly and reliably, but obviously hearing about it, seeing it, and doing it are all quite different things. The guitar in question is pretty nice and clean so Im not likely to go at it uneducated. Id still prefer to touch up the bridge stain rather than end up tearing up the top.

And yeah I did wonder how it would work with runout, or laminated tops for that matter.

[William F.Eden]

I would take Ned's advice on this one Bill...........

[Mark Pollock]

I've seen a small ukulele bridge removed with a chisel and lukewarm water, and there was plenty of grain missing from the wildly figured top afterwards. I would not do it myself, and had I known better and more assertive, I probably would not have seen it that once. No major damage, but not a great gluing surface left behind afterwards.

You can really do this with a heat lamp, though. The rule is, never leave, never walk away, and don't allow it to smoke. Warm it over an hour or so, and it MAY be a lot easier to remove.

If you are already modifying the bridge, you can always re-stain it, you will need to do some kind of color work for your insert anyways.

[Len Biglin]

This kind of removal is normal practice in Violin land , they use HHG and rely on it shattering with a solid blow , they remove backs etc too with a side-ways blow , I dont think its gona work with titebond .

[Russell Vance]

I'm with Len on this one - particularly when there is a technique available that enables a low risk result (heat and palette knife or cold palette knife) .......mind you there are a whole bunch of reality shows that entertain us by showing people trying stuff they probably shouldn't.  But, it's a free world brother - tell us how it goes.

Rusty.

[Joshua Levin-Epstein]

When (and where) I started paying attention to this stuff (late '70s) the chisel was used for removing bridges that were lifting. The point was to break the glue joint and nothing else (like the top or the bridge). It was a lot of light blows (with a sharp wide chisel) and you really needed to know how to read grain.  A skilled individual could do a good job but it was really easy to scar around the bridge and the bridge as well. Remember it was also common practice to install an oversized replacement.... 

Having used the chisel in the past, I would not go back to it. The old Japanese Fenders were surprisingly decent guitars so I would rather touch up or refinish the bridge than try to ignore the top damage..