Martin Pickguard Replacement
Martin guitars are among the most desired and collectible acoustic guitars on the planet. As such, we see a fair amount of vintage Martin instruments walk through our door. While they are generally great sounding and reliable instruments, many have a predictable flaw. From about 1967-1985, Martin guitars commonly featured a black acetate pickguard. At the factory, these pickguards were brushed with a solvent to melt the plastic and then bonded to the top prior to finishing. This production method is responsible for the famous “Martin pickguard crack”.
The “martin crack” appears as a result of the pickguard material shrinking at a faster rate than the spruce top. Since they are “glued” to bare wood, they are unable to move independently. The pickguard pulls the spruce with it as it shrinks and eventually the top can crack in one or more places. In a worst case scenario, the pickguard can distort the guitar top, causing a dip, or even pull part of the top off of the internal X brace. As always, proper humidification is key towards maintaining your instruments health.
When to replace the pickguard
The instrument pictured is a 1971 Martin D-41. If you look between the 1st and 2nd strings, you may note a minor dark line of finish damage running lengthwise from the pickguard towards the bridge. That is one of the places where the crack typically presents. Fortunately this particular top does not appear to be cracked all the way through, though the pickguard itself has curled to the point that a large section of it has simply broken off. Interestingly, the stress relief to the top provided by this missing piece of pickguard likely saved the top itself from further damage.
If a guitars pickguard shows any signs of pulling loose from the body, it is best to pull it, fix the problem and then either reattach the guard if possible, or replace if necessary. (A couple months ago I discussed another common breakdown of plastic parts in another blog post about tuner knob replacement) This guitar is obviously overdue for a new pickguard, so lets talk more about what is involved.
Removing The Pickguard
Pickguard removal on these old guitars is a delicate process. It is best done by a professional to minimize the potential of further damaging the guitar top.
Often times I will utilize a bit of heat to soften things up before removing the guard. To do this, I first protect the surrounding area with reflective foil before gingerly using a heat lamp or heat gun.
Once I feel the material has been warmed sufficiently, I will begin working a pallet knife underneath the guard to separate it from the top. It is important to pay attention to the grain direction to avoid gouging the top here. As you can see in the photo, this one came off nice and clean.
Tracing The Pickguard
Unfortunately, there is a lot of subtle variation in pickguard dimensions, even between guitars of the same model. As such, a prefabricated pickguard simply will not do for this job. Instead I make one from scratch.
If the original guard were sufficiently intact, I could have used it as a template, or possibly even flattened and re-adhered it. However, since it is so damaged, I used a piece of artists tracing paper and a pencil to trace the outline instead. Once complete, I transfer the profile to a blank piece of pickguard material.
Cutting and Shaping The New Pickguard
Once I’ve got the outline drawn, the next stop is over to my tiny model making bandsaw to rough out the shape.
After that, I use a file and/or sandpaper to take the guard down close to the line. I will frequently check the guard against the body to check my progress. I like to use a pickguard caul that I made previously to help lift the pickguard up enough to work it.
Once I am happy with the fit, I use a razorblade to put a slight bevel on the edges of the guard. This softens the line to help blend the guard into the top. Then I am ready to put an adhesive backing on the guard so it will be ready to install.
Applying A Finish Under The Pickguard
Before sticking down the new guard, I want to protect the unfinished portion of the top. Doing so will hopefully prevent further problems in the future.
To do this, my favorite method is to use CA glue as a finish. One could use lacquer, Shellac, etc, but I like CA glue because it is quick and effective. This area will not be visible once the guard is installed anyway so I am not too worried about what it looks like. I simply want to make sure the wood is sealed and protected. As you can see in the photo, I mask off the top to avoid getting finish anywhere but under the pickguard.
Attaching The New Pickguard
With the new guard shaped and fitted, and a protective finish applied underneath, I am ready to put the guard in place. If the look of a shiny new guard is not fitting to the condition of the instrument, some relicing may be done prior to installation.
If I’ve done the rest of my job right, this portion should be pretty quick and easy. I simply mark my position, peel the backing off the backing that I have adhered to the guard, and stick it in place! After a good setup, this nearly 50 year old guitar is now looking and sounding good as ever. If all goes well, she will still be making music for another 50 plus.
About Guitar Repair Long Island:
Guitar Repair Long Island is the area’s premier destination for fretted musical instrument care and maintenance. We fix all fretted instruments, including: guitars, basses, banjos, mandolins, and ukuleles. Conveniently located in Ronkonkoma NY, the shop is dedicated to providing quick, honest, and reliable service. Our vast experience in all aspects of instrument repair ensures that we can help with whatever your needs are. Contact us or book your appointment today