With the value of vintage instruments skyrocketing, guitars that were considered destroyed from a collectable standpoint are now becoming worth a second look for repair and restoration. While they will never command the value and respect of their unmolested brethren, properly restored these instruments can easily become valuable enough to justify the work required.
Guitars that have been played a long time will often have some ill-conceived repairs and modifications and will have often been refinished many times. Our candidate here is no exception. It is a late 50’s - early 60’s Fender Stratocaster.
It has been cut out for humbuckers, has had a fulcrum tremolo installed as a floater and some control cavity mods. While a majority of this would be hidden under the pick guard, having the single coil pickups floating in these large cavities is not going to be good for tone. Then, of course, there is still the issue of the tremolo.
Upon thorough examination of the body I noted these additional problems. All the pickup cavities had routed deeper into the body than they should have.
Also, due to the many haphazard refinishes, the body is now .095” thinner than it should be. The control cavity mod, most likely to add a fourth pot, has a section that is routed at different depths and an odd little wire channel cut in the top.
Thankfully, the neck pocket, output jack cut out and tremolo spring cavity had not been altered. The body arrived at my shop with a majority of the screw holes plugged and some layout lines scribed in pencil onto the top.
While the customer’s request was to restore the body to a state ready for a period solid color finish, he also wanted a repair that would not “ghost” through the finish. As most of these bodies are made from three planks joined together it quickly became apparent that the best course of action was to replace part or all of the top of the center plank. This would actually be easier than the standard “bathtub” type repair and as a bonus possibly allow a tri-tone burst finish if desired.
The first step is to lie out the area to be replaced. Unfortunately, the pickup cavities extend beyond the center plank by about 1/4” on the bass side as shown by the straightedge.
This will not, however, be noticeable from the top. There was also no need to remove the entire top of the center plank and doing so would have taken me into the output jack cavity, so I opted to only remove what I needed on the treble side. The area to be removed is carefully laid out with blue masking tape.
As you can see, there will still be some additional work at the control cavity, but replacing this one piece of wood will take care of 95% of our problems.
To make a good straight, square, clean opening I needed a template. So a square hole was cut into a piece of 1/2” MDF that was exactly 1/8” wider than the area I laid out and a few inches longer than needed. The hole was carefully cut on my table saw. This was aligned over the area I marked out and it and the body were clamped to a work board at my bench.
I installed a 5/8” guide bushing and a 1/2” spiral bit in my plunge router providing the desired 1/16” clearance to match my lay out. Since the opening in my template was wider than my router base could span I needed a way to support the router during the cut to keep it from tipping in and ruining the cut. A strip of 1/4” plywood with a hole drilled through the center was placed over the bushing and secured with a few pieces of two-sided tape.
After making a few dry runs to check my tool path, slightly repositioning my clamps until I was confident there was no interference it was time to start cutting. I double and triple checked my clamps to make sure they would not slip and began. The material was removed in 1/8” lifts, cutting around the perimeter first and then wasting out the center.
The entire area was cut down just far enough to provide a completely clean surface for the repair to be glued to.
Well . . . almost. There are those little terraces over by the control cavity to deal with. Cutting down to that depth would have left me scary thin over the tromelo spring cavity. Since there is more work over there anyway, we will take care of them in a slightly different manner.
By repositioning my template I could cut out the top of the control cavity to the same depth and square it up to the rest of the repair.
This left me with one area still slightly deeper, which I will simply fit a small piece into and glue up with the rest of the repair. The body was kept clamped to my work board until I was ready to glue in the new pieces. This was to avoid any warping that might occur from removing so much of the centerpiece and exposing all this fresh wood to the air.
Now it’s time to prep the new piece of wood to be glued in. This is an Alder body so a plank of Alder with similar grain orientation was chosen. Both the body and the donor plank were left in my shop to acclimate. They were carefully monitored by weight to gauge their moisture content. Both pieces need to be at equilibrium and in stasis prior to any work being done otherwise the repair will fail. To aide in obtaining the best possible grain match, I marked out the grain of the missing piece on a piece of scratch paper and used that as a guide to help select the portion of the plank to be used.
Also take note of the dent left by the strap button on the end, this will need attention as it will be a problem when we trim off our repair.
The cut out was prepped lightly with a hard sanding block to knock down any small ridges and tool tracks. Our new piece was carefully cut and planed to size, paying close attention to the grain that will be seen on the top. Getting the grain to run out the same and appear evenly spaced where it meets the original wood is key to making the repair as unnoticeable as possible. Proper fitment of the piece is also critical for a stable repair that does not “ghost” later. The new piece should be able to be pressed into place completely with moderate hand pressure but need to be tapped out with a mallet. Great care must be exercised here. Try fitting a piece too tight and the body may split, too loose and the repair will be unstable. When tapping the piece back out during fit up one must also be very careful not to chip out any of the wood.
Once I was happy with the fit, all mating surfaces were given a light coat of Titebond, both in the body and on the new piece. The key is in getting the amount of glue just right. Too little and the joint will be weak and the work overall less stable, too much and not only have you made more cleanup work, but you run the risk of locking the joint up hydraulically. This prevents the new piece from seating properly and again makes for a weak and unstable repair. While I could have most likely used my go-bars to clamp this in place, I felt more comfortable using an array of clamps with the body held in a vise.
This allowed me to peek in the tremolo cavity and be sure the new plank was seating properly everywhere and not just at the end and to clean up any squeeze out in there while it was soft rather than try to deal with it when dried. The following day I removed the clamps and fitted and glued the remaining pieces needed at the top of the control cavity. This was done with a clamp and a few small spruce spring bars.
The new wood was intentionally left about 1/32” proud of the original surface and to run long at the end by about a 1/8”. A few strokes with a jack plane brought the new wood down to the proper level quickly. I would rather plane down the new piece than run the risk of having it wind up low, especially in light of the fact that this body was already a bit thin. Using a bottom bearing flush cut bit in my router the end was trimmed back using the original body as a guide. The strap buttonhole mentioned earlier was filled in prior to this, otherwise the pilot bearing would have dropped into it and left a big ugly divot in the end of the plank I just put in. After that, I could restore the armrest bevel across the new wood using my jack plane. A little work with my sanding blocks and it’s ready to have all its cavities routed out to specs.
Using My Stratocaster template, all the cavities are routed in with a carbide spiral cut bit, again working in 1/8” lifts. The holes were drilled for mounting the standard tremolo bridge and for the ground wire to the spring cavity. A final sanding with 180 grit and we are done.
Our body is now as close to factory spec at the time of manufacture as it can be. Even the grain match on the new piece of alder is pretty good.
There are still some minor chips and dings that the finisher will need to take care of but once it’s finished and all put back together it will take a good eye and a close inspection to find the repair.
Originally published in Brian Howard's Guitar Building & Repair Blog.