J Mascis Jazzmaster rewire + goldfoil at the bridge!

This is my friend’s Jazzmaster. He asked me to install a Curtis Novak Goldfoil at the bridge, and rewire the guitar for two separate volumes and tones (using the rhythm circuit for the tones), and a kill switch.

I used this schematic, credit goes to Sigler Music Center in Arkansas:

JM two vol two tone kill sw

What I did differently is that I used linear pots for the volumes and log for the tones, and the kill switch is on (signal passing through) when it’s at the bottom. The switch being on when it’s at the bottom makes more sense because the player is more likely to hit it strumming down. Also, that’s what my friend asked for.

Without strings on, I thought there was too much of a hum in the middle position. I say too much because my setup here isn’t the quietest, being so close to the train and all. That made me think that the goldfoil’s magnet isn’t oriented so that its north faces the opposite direction than the neck pickup’s north. In other words, the neck pup and goldfoil aren’t RWRP.  However, the original bridge and neck pickups measure very close – 100 ohms different, with the bridge being the hotter one, of course. I told my friend about it and we decided to use the Mascis bridge pickup in the neck position. I put strings on it, and no hum.

I haven’t had a chance to really play through an amp and see how I like the volume pots being linear and the tones being logarithmic (it was too late when I was done), so I moved on to non-amplified setup. Basically, the low E string was slipping out of its saddle, and the radius of the bridge (TOM) didn’t fit the radius of the fretboard (9.5″), so I had to file the saddles a little bit.

This guitar is almost done, just need to hear it amplified.


P-Bass fret level and sending off my Jazzmaster

My friend brought his P-Bass in a few weeks back for a setup. I set it up and eliminated most buzz, but it still had some he was unhappy with. It wasn’t anything that come through an amp, but he likes playing it unplugged, so I suggested I’d level the frets.

I leveled the frets and still buzzes. I leveled it again and added more fallaway, and it still buzzes in the middle of the neck. I tried swapping saddles, I tried shimming the front of the neck pocket, and even the back for the heck of it (even though it shouldn’t really help), and nothing really does it. I tried a straight neck and add some relief – nothing. Only thing that helps is raising the action. I think I did a good job leveling the frets, so I don’t really know what’s up with it. I’m going to need more time to think about it and figure it out.


In other news, my Jazzmaster sold on eBay. It was kind of bittersweet because it’s a nice guitar and I enjoy(ed) playing it, but not enough to keep it. USACG’s wrong corners on the body really get to me. So yeah ,that got sold and packed and out the door. So long, my first build! Maybe we will meet again. I hope you end up in the hands of someone who’ll be really excited to play you!


What to expect from USACG parts, and the difference between Japanese and US made Jazzmasters.

This post isn’t really about guitar repair, but I think it answers some questions I had about discrepancies and problems I had with my neck and body, some of them went unnoticed for months. The short version of it is that their bodies aren’t identical to actual Fender Jazzmasters, even after doing the work that’s needed in order to fit Jazzmaster hardware to them. The necks (or at least mine) have a few problems too.

First, I’ll start with some measurements. I asked a friend to measure a few distances on his 65 Jazzmaster to help me understand what was wrong with mine. Here they are:

  • It’s 7-3/16″ (7″ and 3/16″) from the bottom of the neck (where you adjust the truss rod) to the imaginary line running between the centers of the thimble holes.
  • It’s 5-1/2″ (5″ and 1/2″) from the bottom of the neck to the center of the pole pieces of the bridge pickup.

Mine also measured 7-3/16″ from the bottom of the neck to the center line of the thimbles, but the second measurement was off – mine was a little shorter. That explains why an AVRI pickguard fit they way it did on mine:


When the pickguard sits on the guitar so it fits over the thimbles, it sticks back behind the bridge pickup by about 1/8″. Of course, trying to get it to fit over the pickup cavities prevents it from sitting right over the thimbles. I believe this is the big difference between Japanese and reissue/vintage Jazzmasters routes. I confirmed it with an Allparts guard (made in Japan for Japanese Jazzmasters) which fit perfectly over the guitar. A Pickguardian guard also fit perfectly over the guitar, so keep that in mind if you’re looking to buy a pickguard from them for your American Jazzmaster. However, I did make these comparisons in September 2013, so maybe things have changed on the Pickguardian front. By the way, I made a video comparing the two guards. I didn’t post it because it’s 80mb, but if anyone wants to see it, I’ll be happy to upload it.

My fix for this issue was to enlarge the bridge pickup cavity. I did it with sandpaper and a drill with a weird grinding bit. Now I would use a router like a normal person would.

The next issue with the body isn’t really an issue, but it’s annoying nonetheless. The thimble holes aren’t big enough, so they must be enlarged by the customer. This is kind of a pain in the ass because if you try to drill the holes to make them bigger, you’ll have to figure out how to align the center of the drill with the center of the existing holes. If you go the sandpaper route, it’ll take over an hour with 80 grit sandpaper to make them big enough.

Next on the list is the tailpiece cavity. It’s not long enough and the corners are radiused. This means that when you use the tremolo, the plate hits the back wall of the cavity and won’t fully release, so the guitar goes out of tune. The fix is to install the tailpiece, use the arm, see how it works, file or sand the back wall, repeat.

The next two issues are more annoying to me than the ones above, because they can’t be fixed (at least not easily) and they really make this guitar not look like a Jazzmaster.

First, the body is thicker than other Jazzmasters. I noticed that after receiving mine and then looking at some JMs at a local store. I took a caliper to my guitar and the body thickness measured 45.65mm. According to this thread and this one Fender’s Jazzmasters are somewhere between 39mm to 42mm, with older Jazzes being thicker. It doesn’t seem like much, but 5mm times the surface area of a Jazzmaster is quite a bit of material, and indeed my guitar is heavier than any other Jazzmaster I’ve ever picked up.

Then there’s the issue of the radius of the sides. I’m taking about the radius that is cut with a router once the shape of the body is formed. The sides on mine are barely rounded. I mean, they are, but it’s a very small radius. Actual Fenders have a bigger radius and don’t look so boxy. I think Stew-Mac sells the right router bit for rounding over the sides.

Like I said, these two issues are the worst for me. The others I was able to fix and are unnoticeable. The Japanese vs. American route – who cares? So the pickup was moved by 1/8″. I doubt it affects the sound much, and no one would have been able to tell that this is a Japanese route Jazz just by looking at it. These two issues though, the radius of the sides and thickness, I’m still annoyed by them.

On to the neck. The frets on mine weren’t pressed or hammered all the way in, as can be seen in these two images.



Pretty much all the frets looked like that and it really bugged me. They felt stable, but still weren’t properly seated. Since this guitar was my first ever project pretty much, and I’ve never done any fretwork, I sent the neck back so they can seat the frets properly. To be honest, for an almost $300 neck, they should have gotten it right the first time.

Then there’s the truss rod. With strings on, I couldn’t tighten the truss rod enough to get adequate relief out of it, not to mention getting it straight. I don’t know what caused that. Maybe the nut was running out of threads, or maybe the pocket where it sits isn’t deep enough. Cutting more threads onto it and adding a washer helped. Still not a perfect neck, but useable. I also I assume the neck isn’t reinforced (other than the truss rod). Almost every Fender neck I’ve seen had some amount of twist (treble side has more relief), and this one does too. I think adding some carbon rods under the fretboard could have helped that and kept the neck straight, but alas, it’s twist. For what it’s worth, though, the twist has gotten better, so maybe it’s a question of the wood settling.

Lastly, the headstock is very small (like a 50s Strat) and doesn’t look exactly like a Fender headstock. The biggest difference is that it has a little nib (look up a USACG headstock) which I sanded off. The difference in looks never bothered me that much; it might bother others.
I should say that the  folks over at USA Custom Guitars were very nice and tried to be as helpful as possible. When I showed them the American pickguard doesn’t fit right, they sent me a pickguard from Pickguardian. When I showed them Pickguardian’s is the same as Allparts they sent me a new body (I returned the first). However, the new body had the same issues as the first, so I concluded they route them all like Japanese Jazzmasters. They said their CNC plans are made from a 62 or a 63 Jazzmaster, and maybe the outline is taken from a pre-CBS Jazzmaster, but not the routes. At this point I decided to keep the body and fix what I could myself. Like I said earlier, they also took the neck back and fixed the frets problem. So they really were very helpful with every concern that I brought up. However since I worked on that guitar for months, some concerns I felt uncomfortable voicing. For instance, it was over 6 months after I got the neck that I noticed that the truss rod isn’t working properly, and it took me even longer to notice the twist in the neck. Overall I have a fine guitar and I learned so much in the process of putting it together, but if it was all about just getting a nice Jazzmaster, then buying a used reissue would have been the best and easiest way to do it.

Edit: This is a big one. The neck pocket and neck have the tightest fit I’ve ever seen, and that’s pretty cool. I foolishly didn’t align the neck in the pocket with kite strings, and the alignment ended up being perfect. I mean, yeah, there was no room to move the neck in the pocket, so that makes sense.

Fender Jazzmaster Classic Player, its tune-o-matic, tailpiece, and frets.

One of these was brought to me for a fret dress. It’s not a bad guitar! It’s lightweight and the neck felt really nice – skinnier than my USACG Jazzmaster, whose C profile neck is actually a little chunkier than Fender’s C. I mean Fender’s neck are all over the place, but mine seems chunkier compared to most Fender’s C.

As a rule of thumb, I like lubricating all bridge screws of a Jazzmaster. It actually helps them stay in place and they’re easier to work with that way. So I was set to remove the intonation screws from the bridge. Starting with the high E, I kept turning it but it wouldn’t come off. Eventually, the head broke off, and I realized (with some googling) that there’s a little C ring that sits between the side of the bridge and the saddle. To remove the screw, the C ring needs to come off. It’s easy to remove them with a dental pick (and put back with skinny tweezers). Finding a replacement screw where was the fun started.

These Tune-O-Matics look like a Nashville variant, but they have a 9.5″ radius, and they’re made in Korea. Being made in Korea usually implies the threading is metric (and I don’t have one of those things to see what threading it has). I went to a couple of guitar stores here to see if they have a replacement, and they didn’t. I called Fender to ask if they sell replacements, or know where to get any, but they buy the bridge assembly as a whole, so the only way to replace the screw is to buy a whole new bridge. Those are $8 on eBay with free shipping from China, which is mind-blowingly cheap, but I promised the guy to get the guitar done before his next practice. Since I couldn’t verify that the screws are actually metric, I decided to bite the bullet and ordered a set of screws and a set saddles from Stew-Mac. I figured that if the new screw won’t fit in the existing saddle, then I can replace both saddle and screw. The Stew-Mac screws fit the saddle, but they’re a hair shorter than the original screws, so they don’t fit in as tightly. They are functional though, so I wouldn’t mind using them again. So if you read this and need a replacement screw, either get a whole bridge (and maybe those ones on eBay do have metric threading?), or go ahead and get some from Stew-Mac.

The tailpiece on these guitars is the usual shape of a Jazzmaster tailpiece, but the arm is threaded into the socket, as opposed to just being pushed in. I know some people have bad experience with their tremolo arms where they fall out or keep swinging, but that’s probably because they don’t push it all the way in, or they use import parts which I believe aren’t made with the same accuracy that the US parts are made with. Anyway, the arm moves in the socket a little (even when threaded all the way) so it rattles, which is annoying, but it’s also not as sensitive as the original.

Now the Tune-O-Matic seems like another fix people are into, but not me, and definitely not this TOM. I never noticed it with other TOMs, but the intonation screws move back and forth. They just sort of pop away from the bridge a little bit (but don’t come off completely, because of the C ring). I don’t know if it’s because of the tremolo rocks the saddles, or just a bad design, but it’s a thing. This means they rattle (which isn’t a big deal because it’s not heard through an amp), but worse, it makes it go out of tune.

The last gripe I have with these guitars is that the frets seem to tarnish quickly. I leveled, crowned, and polished the frets and they looked like a million bucks. Then I put strings on and played it a little, and I noticed these scratches along the frets. It’s not the strings that caused it, because my JM has 12-52s and its frets still look like new. My guess is that they use a higher ratio of soft-metal to nickel in those frets.

TL;DR – Nashville style TOM intonation screws would work on these TOMs (like those available from Stew-Mac). The rhythm section knobs (roller knobs?) take 16/32″ hex screws. I thought they’ll be metric, but they’re not. Tremolo arm is threaded which makes it not sit tight in the socket, and it’s not as sensitive as the original. TOM intonation screws don’t sit tight in the bridge, so there’s rattling and the guitar goes out of tune a little (I don’t think loctiting would work, nor do I like doing that). The frets are a little soft and tarnish quick. Otherwise it’s a pretty great guitar.

Jazzmaster bridge can’t be lowered all the way to the pickguard (fixed)

This is something I’ve been trying to figure out since before Christmas. I got a Fender USA Jazzmaster bridge (what I thought was AVRI), and I couldn’t lower it all the way down to the pickguard. There’s a gap of about 1/4″ between the pickguard and the bottom of the channel. Image

The height screws each have a slot that runs along them, but that wasn’t the problem. I also ruled out any obstruction within the posts because both screws go in the same amount. That is, the pointed side sticks out the same amount on both sides. You can see in the picture above that the bridge is parallel to the body. Here’s one of the screws with the slot that runs along it.


Here’s how far the screws go in the posts:


I started digging around and I figured that the bridge I have isn’t from the AVRI (American Vintage Reissue) series. The AVRI line was discontinued this year (I mean, in 2013) and replaced by the American Vintage Series (no one’s calling it AVS yet). My bridge was from the latter (part number:0054460000). Since no one with an AVRI Jazzmaster at OSG ran into this problem, I realized that the bridge is the culprit. The advice I got from OSG was to buy new screws from Guitar Parts Resource, but I couldn’t see how those would make any difference. I already have new screws! They came with my bridge. So in a desperate attempt to figure out what’s going on, I decided to message offset guitars aficionados Mikes & Mike Guitar Bar. When I told them the bridge isn’t AVRI but AVS (I’m making it a thing), they told me that these Jazzmasters, which are modeled after 65s, have a taller neck and Fender must have compensated for that at the bridge.

I took the advice I got at OSG and bought a pair of new screws ($3) along with a new channel for the bridge from Guitar Parts Resource, but not before verifying with them that the channel is for 62 reissues, i.e. AVRI. One of the two had to be the problem, and I didn’t feel like ordering one first, then ordering the other if the first didn’t solve it.

I got the package yesterday and the problem is solved! It’s the screws! The screws from Guitar Parts Resource are shorter than the ones that were shipped with the bridge, and they go all the way in the posts. Here’s a picture of two screws side by side:


At first I thought that Fender just made new bridges for the 65 reissues, but in reality that doesn’t make sense. Because the necks are taller, lowering the bridge all the way to the pickguard probably made it buzz like crazy. On the other hand, it could be useful to get the bridge really high in case the player uses 2-3 shims and likes a high action. Making a new bridge is a lot more expensive than sourcing new screws (not to mention making things untrue to the vintage models), so Fender went with the new screws.

So in case anyone ran into this problem and didn’t know what to do, the answer is to buy a pair of screws from Guitar Parts Resource or Angela.

November 12th, 2015 EDIT: I’ve never worked on a 65 Jazzmaster, but I talked to someone I know today and he said that neck pockets on those are angled, so this built-in neck angle necessitates a taller bridge. Also, I think the screws I got from Guitar Parts Resource might be made in outside the US and have lower tolerances, because when I dig into the guitar the bridge starts lowering itself slightly. Also, with the neck shimmed on my Jazz, the bridge is already pretty tall, so these screws would have worked for me.

Wet sanding, polishing, shielding, and a gouge!

It is advised to wait a month before starting to sand, because that’s how long it takes lacquer to reach its practical hardness. I didn’t have the patience for that, so I started wet sanding after three weeks (as I mentioned in my last post). Here’s what the guitar looked like prior to sanding:


I started by filling all the holes, with the exception of the neck pocket holes, with beeswax. The wax prevents water from going in them, swell the wood, and therefore make the lacquer above it crack. I held off on buying beeswax because any store that had it had just a tiny bit of it, and it seemed to be really hard to the point where I won’t be able to easily cut it and shape it. The size really isn’t a problem, because I think I can easily do 30 guitars with the small amount of beeswax that I got. As for its hardness, it is indeed hard, but I could cut a small piece with a knife, and then roll it in my fingers to make it fit the holes. I then cut the excess with a ruler or something, but I also discovered that if you sand the excess, it won’t mar the finish or anything. At best it clogged the sandpaper. Unfortunately, some holes weren’t 100% plugged, and water got in them and caused cracks. Next time I’ll use more wax, wipe off the guitar more often, and really just use the water to clean the sand paper. For what it’s worth, though, the cracks were very thin, and I don’t see or notice them anymore.

Besides cracks, I also had to deal with sand throughs. I wrote in one of the last posts that I gave up on spraying clear over black and ended up spraying four coats of black over the five coats of clear I had on the body. I should explain why four. For “thin skin” finishes, it is recommended to spray 9 to 12 coats of clear over the color coats. I already had 5 coats of clear on and a very thick first coat of color, so I thought four (for an overall of 9ish final coats) should keep it thin. I also tested it before spraying and four coats were enough to not sand through. However, I think I started sanding through to the clear coats underneath a little bit. The only indication I have for sanding through is that the water (as I was sanding) wasn’t pure black like it did earlier in the sanding, it was a little diluted. Usually, sanding clear lacquer makes the water turn white, but I didn’t get that far. However, the sand throughs must be minimal, because I can’t see any discrepancies in the finish. Still, next time I’ll put on six final coats or more (if I don’t spray clear).

The sand throughs were a result of how long and hard I had to sand. Sanding took maybe 5-6 hours (if not more) starting with 800 grit all the way through 2000, and I had to press really hard to sand anything. This was probably the result of how long I waited to sand. For instance, the neck of this guitar I sanded five days after I finished spraying, and it required minimal effort to do. Next time I’ll wait five days, then test the lacquer by pressing with my nail at a hidden spot. If there’s no impression, I’ll wet sand, and then let it dry for 20 more days, then rub it with a compound and polish. The polishing can be done along with the wet sanding, but since it’ll hang to dry and collect dust, I prefer to polish last. Speaking of polishing, when I first started reading about how this is all done, I thought I’d need special material to rub on the compound and polish. So I bought a buffing pad and I’ve never used it. The reason I’m not using it is that I first wanted to practice wet sanding and polishing on a scrap piece of wood with lacquer, and I didn’t want to waste the buffing pad. For that, I used a white cotton t-shirt. The results looked great, so I stuck with it. It’s best to use an older t-shirt that has been washed a bunch of times. This way it has less lint. The compound and polish I use are Meguiar’s Ultimate Compound followed by Meguiar’s Ultimate Polish (in this order).

Here’s the end result. It’s hard to take a picture of a black finish, because it really just acts as a mirror. I think the Meguiar’s products do a good job and make it look real shiny.


Shielding the cavities is pretty easy and cheap, especially if you buy something like this (2016 EDIT: this tape isn’t conductive on the sticky side. It’s not a big deal when shielding body cavities, but it can be a problem in other instances), which is way cheaper than copper tape and is just as effective. Taping along the edges with one long piece is a no go. The way to do it is cut small pieces and overlap them. It’s really tough to get around the tight curves like the one at the bottom of the cavity (where the jack would sit). Here’s the body all shielded:


And a few close-ups:




I took a picture of the back when I took the pictures of the shielding, and that picture looks better than those I already posted. So why not show it off.


Here are things that I learned for next time:

  • Don’t wait 30 days to sand (but do wait 30 days to put the hardware on, etc.), just five days or maybe a week.
  • Plug well with Beeswax and don’t let so much water get on the body.
  • It’s better to go thick and not thin skin than sanding through. I was lucky this time around, but might not be so lucky next time.

As for the gouge — too soon for me to talk about it. Too soon.

On the failure of spraying black lacquer

I haven’t updated here for a while, but that doesn’t mean I haven’t been working on the guitar. It’s just that the semester was ending so I had less time to work on it, and certainly less time to update here. However, I finished painting the guitar, but with some compromises. People on the internet can be very cryptic, and I’ve seen the variations of “black is the hardest color to spray” peppered around different forums without any explanation. It never clicked why it’s so hard to spray until I started spraying clear.

I mentioned in the last post that I was getting some dust under the clear coat. Honestly, it wasn’t that dramatic, but I couldn’t just let those specks stay there. So what I did was spot sand where I got the dust, then respray clear in those areas, then shoot another coat. Of course, the new coat trapped dust also, and I had to repeat the whole processes. It felt like I was taking two steps forward and one back, and life is too short to be sanding so much, so I looked for some solutions online.

The first suggestion was to wipe off the body with a tack cloth between coats, and this is actually very helpful as it clears the body from all dust and specs prior to spraying it. The problem is that the spraying disturbs the surrounding dust, and the basement I spray in is just too big and dusty to not have random dust specks flying around. So it didn’t really solve the problem. Other suggestions were to build a temporary spraying booth and that’s where I was headed.

The temp spraying booth that looked the most promising was a PVC cage lined with clear plastic tarp. The idea was to build a 3x3x3 cube so that I could fit it in my storage unit without taking it apart after spraying. A better booth is one I could stand in, but I don’t have that kind of real estate available. The only problem was that no hardware store in Chicago was carrying 3 way PVC elbows, so there was no way for me to build that cube and make it sturdy.

I was pretty bummed because I really had no other solutions, but then it hit me. Get a huge bin from target, mount it on a wall, mount the guitar in it and voila! I got a huge bin, cut a little slot so I can hang it on one of the brackets I use for drying the guitar and started spraying. I also got a big spot lamp so I can see any dust movement. I don’t know if it was the improved lighting or the the bin (after all, it made for smaller quarters), but dust was flying left and right. Also, the bin, while huge, didn’t leave much room for turning the guitar to spray the opposite side or edges. I had to be very careful when turning it so that it doesn’t bump the sides of the bin. So overall the bin might have been an improvement, but it didn’t solve the dust problem completely and made spraying even longer. Now my options were to either spray clear and live with the small specks of dust, or finish the guitar in black with no clear.

It’s worth it to segue and discuss why anyone even bothers to spray clear. It makes perfect sense with metallic colors. Sanding them would smear the metal flakes around, so clear must be sprayed and then sanded and buffed. But what about solid colors? Some people say that it makes the color looks deeper and more vibrant and that’s true, but the reason it all started is because Leo Fender did it. Above all, Leo Fender was a businessman, and doing a whole guitar in colored lacquer is more expensive than spraying the minimal amount of color coats and spraying clear. The claims that the color is deeper with clear coat have some grounding. I did an experiment on my guitar by sanding down the clear in one spot all the way to the black, and then wet sanded and polished it. I also wet sanded and polished a spot that had clear coat. The polished clear over black did appear shinier, but I thought the difference was very minimal. It was so insignificant that it didn’t show at all in a picture, and it took looking it under several different lights to see the difference. (It should be noted, though, that the ultimate test is to have two larger pieces of wood painted differently and see how they compare.) Anyway, since I’m not a fan of super shiny finishes and I’m an even lesser fan of sanding out dust after every coat, I decided to finish the guitar with 4 more coats of black and no clear.

As of the writing of this post, I’m halfway through wet sanding (it’s been three weeks yesterday since I finished spraying), and there are some problems, but that’s for the next post.