I'm back! I had to take a month off from the blog to move into a new apartment. This coupled with my new shop move back in May has kept me away from the bench more that I would like.
So, here we go!
Here is a cool old 1964 Fender Jazzmaster on the bench. It sounds really, really killer . Just a few minor things to get it back playing sweet. The guitar needs new frets, a new bridge, and the pick guard flattened. You can see below how badly the guard had shrunken and distorted. This is common with old Fenders.
The original bridge, while technically in fine condition, is a poor design to begin with. The low break angle of the strings running to the tailpiece is really shallow, so there is not much down pressure holding the strings against the screw saddles. It is easy on these stock bridges to accidentally pull the strings out of the bridge grooves while playing. Ideally you want to be able to keep your string spacing constant.
The customer wanted to go with a new Mastery bridge as made popular by Nels Cline of the band Wilco. You can see below how each string now has a dedicated slot in the new bridge. The replacement is super easy. Just loosen the posts on the old bridge and it pulls right out of the existing "thimbles" mounted in the body. The new bridge just drops right in. Set the action and adjust intonation and you are all set.
We will install the new bridge later after the pick guard issues are addressed.
I pulled the neck since we will need to access the truss rod during the refret. This will also make it easier to pull the pick guard so it can be flattened.
The neck is stamped "4 Nov 64 B". CBS took over Fender in 1965, so this guitar is right at the end of the often preferred "pre CBS" era of Fender's history. I believe the 4th of November 1964 was a Wednesday. Actually though, the "4" denotes the model, not the date. The "B" is for the neck width being "normal".
And no, I do not know this information off the top of my head, see this link for where I pulled references from. (note: I just flashed back to all of the college reports I had to write and giving due credit. I guess I did learn something in college ...).
Below is the neck pocket and the shim that was used to further decrease the guitar's already low neck angle. I will remove it when I bolt the neck back on (screw really, not sure why they are referenced as "bolt on"). It can always be put back in if I do not like the neck angle. Also take note of the the "x" looking depression in the pocket just below the shim. This is a sure-fire giveaway that this guitar has been refinished. The old Fender factory would pound nails into the neck pocket and various areas in the pickup or control cavity. This would allow the person spraying to shoot finish on the face and then flip the guitar over onto the nails that act like stilts. Then they could finish spraying the back. This nail mark should be bare wood as the original nail would have been pulled after the original spray work was completed. Knowing the originality of the finish heavily impacts the value of vintage guitars, so know what you are buying. This customer got a deal on the guitar and was aware of the refinish when he purchased it.
Below is the pick guard flipped over. Take note of the grounding plate that is sandwiched between the electronics and the pick guard. Everything appears to look original. The pickups are mounted directly into the the body.
Here is a close up of the bottom primary controls. Jazzmasters have dual set of controls for volume and tone - one in the traditional location at the bottom of the guitar and another set on the upper bout.
The upper bout volume and tone controls are roller wheels. Pretty slick for the 1960's. You choose between the two sets of controls by a small switch on the upper bout. What is cool about this is you can set two independent volume and tone sounds and then select between the two on the fly. Also you can use the pickup selector with both sets of controls. Again, really slick.
The control cavities have formed brass / copper tubs that fit into the guitar to help shield the circuit from outside noise. This is a pretty heavy-duty solution compared to modern guitars that use either copper tape or shielding paint. Again (again), very slick.
Now that the electronics and shielding plate have been removed from the guard, we are ready to start flattening it. I use a heat gun to gently (GENTLY!) warm up the plastic. This allows the the guard to soften and begin to relax. Since this is a multi-ply laminated guard, I heat from both sides to get everything warmed up evenly. I keep my hand right next to where I am heating with the thought that if it is too hot for my hand, then it is too hot for the plastic. When it is softened, I remove the heat and use hand pressure to push down the warped sections against my aluminum plate. This guard was difficult to flatten completely, but it is now much flatter than it was initially.
The warping of the pick guard is caused by the plastic shrinking over it's 48 or so year life. The pickups and bridge mounting thimbles are independent of the pick guard and their locations to do not change over time. This causes the guard to become hung up on these elements (along with the guard mounting screws) and to distort where it is restricted from shrinking. The metal shield plate also retains the original dimensions, so it causes further issues for the moving plastic pick guard.
The pickups do not fit in the shrunken guard like they once did. This is not from heating the guard, but from the previously described shrinking effect.
The pick guard needs to be opened up in order for both pickups to fit easily and for the guard to mount flush.
I use a cabinet scraper to open up the pickup holes. You just need to be careful not to crack the guard while doing so.
Now for the bridge mounting thimbles. You can see how they do not line up with the shrunken guard. I use a dowel with sandpaper to open up these holes in the guard. The holes will become out-of-round, but will be covered by the bridge. The benefit of a flat pick guard outweighs this minor detail in my eyes.
The guard is now fit to the bridge thimbles in the blurry photo below.
Now that everything fits and the guard lies flat, the grounding shield and electronics are reinstalled onto the pick guard and put back onto the guitar. Since the guard has shrunk, many of the mounting holes do not line up with the body. I start with one screw and then jump across the guard to another screw and install them in a spread out pattern, similar to tightening the lug nuts on your car tire. Once all the screws are started, I go back and snug them all down.
Now for the neck and it's new frets. I use a large soldering iron with a ground end that sits nicely on the old frets to heat them up. Heating them loosens up any glue and makes the fretboard sweat a little bit, which allows the frets to be removed with minimum damage to the fingerboard.
I use flush-ground end nippers (like many other repair persons use) to pull the old frets out. Note that I am only squeezing the pliers and not actually pulling with them. Keeping the face of the pliers in contact with the fingerboard keeps the board from chipping up and the business end of the pliers lifts the fret up. I usually hold the soldering iron in my left and and follow behind it with the pliers. The photo below just shows the pliers as my other hand was taking the photo.
All of the old frets are out now and we can get to installing the new ones. First the neck needs to be straightened via the truss rod. Once straightened, the board can be sanded flat and the radius maintained. New frets are then pounded in with a hammer on my buck-shot filled bag to ensure they go in solid. After the new frets are beveled, trued, crowned and polished, it's ready to reinstall the nut and screw back onto the guitar. Remember to adjust that truss rod to give a little relief where you like it before reattaching the neck. You will most likely have to pull the neck again after you string it up to dial in the truss rod, but at least you can get close (or better yet lucky) on the first try.
Everything is back together. The pick guard is nice and flat and the new bridge is installed with both the action and intonation adjustments made. The guitar plays really nice with the new frets and bridge. It's sad to see her go, but you have to move on. Maybe I'll have to keep my eyes out for a Jazzmaster of my own ...