Shaving an Acoustic Guitar Bridge

This acoustic guitar saddle is too low. And the action's still too high. 

This is an acoustic guitar bridge and there’s something wrong with this picture. Well, the picture’s ok, but there’s definitely a problem with the guitar. 

You can see how low the saddle is. The string’s have no ‘break’ angle over it—that first string sits almost horizontally on the saddle. 

This means the strings impart very little downward pressure to the saddle. No downward pressure means that much of the strings’ vibration is lost rather than being transferred into the guitar top (which is what provides most of your tone and volume with an acoustic instrument). Poor tone and poor sustain.

Too shallow a string-angle over the saddle means poor tone transfer to the guitar top and pickup.

Too shallow a string-angle over the saddle means poor tone transfer to the guitar top and pickup.

Add the fact that this guitar has an undersaddle transducer pickup installed and we’ve got a recipe for poor amplified sound too. Remember that piezo pickups rely on pressure to sense the string vibration. 

Why not install a higher saddle?

Well, we could. Problem is, the saddle is this way for a reason. It’s been lowered repeatedly over the years to compensate for the (very common) geometry changes that many acoustic guitars experience. 

String tension takes a toll and, over time, the action can slowly get higher and higher. As it does, the saddle is often lowered by players or repairers to keep things playable. 

Until it can’t go any more. 

That’s were this instrument is. The saddle’s so low it might as well not be there but the action is still too high. 

Sounds like time for a neck reset

Yep. It’s an ideal candidate.

We’ve talked about neck resets before. The neck is removed and the angle it attaches to the body is altered so that the string action can be reduced. 

The problem is, on many guitars, a neck reset is a big job. And, sometimes, it can be difficult to justify the expense. In an ideal world, we would reset the neck on any guitar with this problem. It's not always an ideal world, though. 

Is there an alternative?

Shaving the bridge

It’s possible to shave wood from the top of the bridge. This lowers the wooden part so that a saddle can protrude more, giving more scope for lowering the action while still maintaining a reasonable break-angle for the strings.

The Problem 

Now, this is a very tricky situation. 

If you’ve got this sort of problem on a guitar worth a couple of hundred bucks, go for it — shave away. It’s not a big deal. 

However, if you’ve got a guitar that’s valuable, or that has collector appeal, or that you just really like, you really want to consider the ramifications of this one. Shaving the bridge can potentially impact the instrument’s value—many buyers don’t look on it kindly. 

This particular instrument is a nice guitar, with a bit of vintage under its belt. The owner and I had a very frank conversation about the implications of this job on the guitar and on its value. 

The upshot? Please shave the bridge.

Gerry’s Note: These decisions can make me a little uncomfortable. Quite honestly, I don’t really like shaving bridges on nice guitars but I have to weigh my discomfort against the chance of someone less ‘careful’ doing the job instead (I once read someone—I think it was legendary repairer Frank Ford—say something along those lines and it’s stuck with me). Hope this doesn't sound too cocky. ;-) 

Bridge Shaving Complications

This is what lurks underneath that bridge. It's a Takamine-style palathetic pickup. 

In this case, things are more complicated than they might be on another instrument. The guitar has a rather complicated undersaddle pickup installed. It’s similar to Takamine’s Palathetic pickup which includes a relatively bulky metal carrier inside the guitar, six ceramic cylinders that protrude into the bridge and make contact with a metal strip. This strip, in turn, contacts the bottom of the saddle. The strip is held in place with recessed screws. 

Any bridge shaving needs to take this into account. We don’t want to shave too much off and we need to re-recess the screws holding the metal strip in place. Carefully does it here. 

The Work

The top of the bridge is shaved off. This is really the easy bit. I use some small block planes (nice sharp ones) and when I’m down to where I want to go, I can smooth things out with some sandpapers. 

Then we need to lower the saddle slot, however. This is important. The slot becomes shallower as the bridge gets lower and if it’s too shallow, the saddle will either tilt/topple under tension or won’t make a good coupling the pickup or acoustic tone. 

Routing the slow lower needs to be done carefully because we have to bear in mind the pickup elements are poking through and we don’t want to rout too deeply into the bridge or even into the guitar top. 

Lowering the top of the acoustic guitar bridge.

Lowering the saddle slot to compensate for the lower top.

Finishing Up

This bridge had a little lacquer on it originally, so we’ll just touch that up. Then it’s a matter of cutting some new string slots and reaming the holes a little wider to accept the bridge pins (they get less wide as they go down so shaving the top exposed a narrower section that would have left the pins sticking out too much). 

The end result is a guitar with a nice action and a reasonable saddle height. It plays nicely and sounds good again. Maybe that's what's important. 

Reaming bridge-pin holes to get a good fit after bridge shaved

Reaming bridge-pin holes to get a good fit after bridge shaved

Finished bridge. The bridge is lower. The saddle sits in a better position and the action is more playable.

A last word

That said, I should still reiterate that a neck reset is really the best way to address this problem. Shaving the bridge can devalue an instrument (possibly by more than the cost of the reset if you have a really nice guitar). There’s a place for this job, but expect me to push back a bit if we ever discuss it.