Jazznado

October 3, 2021

Haven’t been using the shop for much of anything lately, so starting a guitar project. I tend towards Fenders, but not interested in making a replica of anything. There are elements about the Jazzmaster, Telecaster, and Toronado that I like, so decided to bastardize all three.

I started out favoring the Jazzmaster, being a long time fan of Elvis Costello, Thurston Moore, and Tom Verlaine. Then decided I liked the overall size of the Toronado better. But I also want a cutaway and a Tele headstock.

Electric Herald is a fantastic resource for full-size guitar body and neck templates. I dreaded reinstalling my old version of Illustrator to work on these files, but turns out Inkscape (freeware) was great for this. (Other that crashing all the time during bezier curve edits that is. The current developer build seems slightly more stable.) I pasted the Toronado template on a locked layer. This allowed me to keep critical dimensions like the neck pocket intact, and trace over them on new layers for the tweaked body design and other separate elements such as the pickguard and bridge. [Note: the tremolo and bridge locations are just estimations in the drawing, will locate those after the neck is finished and installed.]

I printed out the full size templates on plain 12×18 paper. Adobe Reader worked great scaling the prints correctly (using print as poster), and lapped the drawing over several pieces of paper. Not difficult to line up the pages provided there’s a center line, along with something of known size in the seam of print. The bridge pick-up happened to span the seam, so when taping the pages together, the bridge pickup could be measured against the twin neck pickup to figure out how much overlap was needed for the proper dimension.

I cut out and glued the printed templates on 1/4″ MDF, cut as close as possible with jigsaw, and then sanded to the lines. I transferred the center lines to the template edges then scraped off the templates. These patterns will be used to make the final router pattern templates for cutting out the actual parts. The 1/4″ material is easy to shape by hand into an accurate template, but it didn’t feel thick enough to use for pattern routing thick wood parts. They were thick enough to pattern rout copies in 1/2″ MDF though, which will then be used for the neck and body blank.

At Edensaw I found a nice 8/4 x 10″ Basswood timber for the body and some 6/4 Maple for the neck. I’d planned to paint this guitar not stain it, so Basswood was a nice find, it’s relatively light next to the pseudo Mahoganies. I was able to glue the body blank out of 2 pieces. I forgot to thickness to final dimension before gluing together. Since the blank is too wide for my thickness planer, I had to take the final 1/8″ off with a hand plane. I don’t have a scrub plane so it took a while.

I don’t own a band saw, but my jigsaw worked just fine roughing out the shape. Basswood is relatively soft, but I imagine it would work well on all but the hardest woods. I used the off-cuts to support the router during the final pattern routing. I tried to get as close to line as possible to make the routing step easier.

I attached the template to the blank with double stick tape, then stuck the guitar blank and the off-cut supports to a large piece of MDF with double-sided tape as well, then clamped that to the table. This way I was able to easily rotate the fixture as needed during the routing process.

Since you need to use a top-bearing bit for this method of pattern-routing, the bit has to run at full depth during the operation. It’s safer to use a series of separate bearing bits with increasing bit length, but I only have a single 1.5″ long bit, so checked everything multiple times to see that it was secure before I started. I even planned the order of the cuts and did a practice run with the router off to make sure there were no obstacles and the router base had plenty of support. Wood has a tendency to tear-out violently or even shatter if you don’t route in the right direction. On straight-grained wood, I prefer to go downhill when routing curves. That is, treat each wide dimension in the bout like it’s the top of a hill, and rout in opposite directions from that high point. This minimizes tear-out, but can be dangerous because half of the rout on each bout is a climb cut. Since the bit rotation is going in the direction of the router travel, the bit wants to dig in and ‘climb’ through the cut at ~20,000 RPM, trying to pull the router away from you. It’s not bad if you know what to expect, but I’m glad I didn’t try to do this with a 1/4″ thick pattern.

The top-bearing bit wasn’t long enough to cut the entire thickness without pulling the shank out of the router further that I was comfortable with, so I switched to a 2″ long bottom-bearing bit and flipped the piece over for the final 3/8″.

In town I picked up a cheap Harbor Freight oscillating spindle sander to sand the body contours. It’s not a dream tool, but it is decent for the price. It’s fairly aggressive and doesn’t bog down. Being able to easily swap out the spindle drums for all the different radii on a body shape is great. It would have take much, much longer to sand out all the router chatter without the it. I’ll definitely use it for other things.

The thing I dreaded about building a guitar was having to buy a lot of specialty tools. I have planes, belt sander, palm sander- all of my tools are great for flats, but contours are not something I do very often. I made a deal with myself that I’ll only buy tools that I’ll use for other things, which means I’ll make any specialty jigs for carving the neck radius and cutting frets.

Anyway, I’ll wait to rout the tremolo, pickup, and control cavities until the neck is installed, so on to the neck next.

I’m attempting to make a 1-piece neck with a built-in fingerboard, so trying to order the steps very carefully to make this as easily on myself as I can. Ideally I’d like to do all the steps that require square flat edges for registration first before shaping anything- drilling machine holes, inlays, cutting nut and fret slots, etc.

After planing the maple neck blank to thickness, I drew center lines on it and marked one reference edge that I’ll use through the subsequent steps. Then I bored the machine head holes in the templates, then transferred to template to the neck blank and drilled the final holes. (I used a 3/8″ bit and will ream the holes to 10mm later.) I drilled through the back of the headstock, the final shaping of the front of the headstock will remove any blowout around the holes. After drilling, I used 3/8″ drill bits to register the neck pattern to draw it on both sides of the neck.

October 9, 2021

Waiting for parts to finish the neck, so meanwhile I’m tweaking the design. I decided on P90 pickups. I’m going to wire it like a traditional Jazzmaster with the rhythm circuit. I found a complete wiring parts kit, just hope the 1 meg-ohm pots aren’t too bright. As I understand it, P90 and Jazzmaster pickups are actually much different, the bobbin on a Jazzmaster is much thinner but wider so the coil has a different magnetic field. I thought about winding my own pickups, but found a well-regarded set from Tonerider for around $100. I got the Alnico IIs, which will hopefully tame the high impedance pots a little. I put Lindy Fralin pickups in my Tele, and don’t need another bright guitar.

Also changed to a Strat-style input jack, seems like good compromise between face- and side-mounted jacks. I tweaked the pickguard design to accommodate that, but want to get moving again so I don’t tweak this thing beyond all recognition, which is my nature when drafting. I have all the parts I don’t need yet, but still waiting on the fret wire, truss rod, and bridge.

October 16

Parts arrived a week late but undamaged. I installed the truss rod with a Rosewood skunk stripe. I did not have a 7/32″ router bit, so spent some time setting up the router table with a 3/16″ bit so I could to flip the work piece and run the fence against both edges to make sure the route was centered and would still get a snug fit. Afterward I had to drill the clearance hole by hand for the spoke wheel adjustment knob. I drilled a step hole, 3/8″ for the shaft step and 5/8″ for the knob. I almost screwed up and widened the slot from the bottom. It’s nerve-racking doing these operations on a blank I spent so much time truing up. I expect this feeling will only intensify as I go on.

Started shaping the neck after the glue dried. I used a jig saw for the general outline, then decided to shape the basic contours with hand tools instead of the router template. I did use the spindle sander for the the headstock contours, but used a hand plane and spoke shave for the neck. I did use the router to dimension the headstock thickness down, and the spindle sander to shape the ramp to the fret board.

I made a radius jig. There are tons of ideas for these on the internet. I used materials on hand, some inexpensive Home Depot pine and 1/2″ plywood. The fingerboard radius is 9.5″. The router sled rides on Delrin bearings I turned and bored on the lathe. The carriage rides against the backer board, 0.025″ UHMW tape on either side of the carriage lets it slide easily and still be a snug fit without slide-to side play. The neck blank is just stuck to the backer board on the center line with double-stick tape.

Jigs, though. I’m spending more time on jig building than anything else. As you can see for the top of the above photos, I even experimented with coving on the table saw to make neck cradles and radius sanding jibs. Since I have a 10″ table saw blade, was able to cut a passable 9.5″ radius cove by pushing the stock very close to sideways across the blade. Lots of shallow passes and clamps recommended.

I still need to shape the back of the neck, but will wait until the frets and inlays are done. Made jigs for these too.

I used a full scale print of a 25.5″ scale Tele neck to lay out and scribe lines on a scrap piece of Lexan. On the mill I notched to the right of each scribe line with a 1/8″ router bits. It was easier to line one edge of the bit up with each line rather than try to center the bit over each line. Clamping a plywood scrap behind the Lexan helped contrast the lines and prevent chipping.

For the frets, I put together a miter box from pine scraps and some other hardware I had lying around. I don’t have the saw yet, so made one side of the jig adjustable (overdid the slot width a little). The zero-clearance slots are lined with 0.125″ Delrin, which will bear on the some of the same 0.025″ UHMW tape that I’ll apply to the saw blade to give the sawtooth set some clearance.

The notched Lexan template will register with a pin in the miter box slot. It’s roughly 1″ below the fret slot depth so there’s no chance of damaging the saw blade.

October 23

Before shaping then neck radius and back, I laid out the center lines on the neck and guitar body. I used some bar stock to extend the neck taper to make sure the neck is centered on the body. The layout lines will come in handy later when ready I’m ready to route the neck pocket and set the bridge.

I made a jig for the machine head pins, but turns out the pin locations are all slightly different, so had to fill the holes with sanding dust & superglue and try again. The second time around I clamped a straightedge to the head, dabbed the tips of the pins with blue sharpie, then pressed the tuner into head when aligned against the fence. This left a blue dot on the pin centers. I made sure to keep the machine heads in order.

Found some 12×17″ 3-ply pickguard material that was big enough for the design. It’s ABS and decent stuff, but the Ivory has mint bias to it. It tends to wreck the auto white balance on my cellphone camera, and give the Bassword a distinct Play-do hue. If nothing else it’s good material to practice with. I used a 1/4″ MDF for the router template which worked fine. I made different jig for the pickup routes out of 1/2″ MDF though. Actually it was 2 layers of 1/4″- I placed the P90s on layout on a piece of 1/4″ MDF, then wrapped strips of 1/4″ MDF around the pickup covers with double stick tape, then routed out the holes. Then I taped the jig to the pickguard and cut the P90 slots. The material machines well, it’s not brittle like Lexan, cut more like, well, ABS.

The fret saw finally showed up from Stew Mac. I got the one that cuts on the pull stroke. I stuck some 0.02 Delrin to either side, which will provide clearance for the Delrin guides on the miter box and also provide a depth stop for the fret wire slot.

I installed pearl dots and black ABS side dots. Installed the dots with superglue and the side dots with Acetone. The pearl sanded more easily than expected.

The neck jig worked well. It was a little tricky centering the neck, so I measured the cuts on each side for the first few passes to double check the alignment. You can also do this by touching each side with the raised router bit with the router off.

I really like the shape of the neck on my Telecaster, so took it off that guitar so I could more easily copy it while shaping this neck. I got a Shinto saw rasp for this, but it was almost too aggressive, so switched to a file and scrapers to do most of the shaping. Scrapers are surprisingly efficient at this type of work if tuned up well.

I sanded the fingerboard through 800 grit before installed the frets. I cut a 15 degree slot for a file in a chunk of Maple, which made quick work of filing the fret ends flush and leaving a consistent bevel on the edges.

The Jazzmaster has some known issues with the bridge and tremolo, mostly having to do with string break angle. To alleviate this, I cut an angled pocket. The shims on either side of the template resulted in a neck angle of 1.25 degrees.

I was able to use the body neck pocket to route the matching cutout in the pickguard. I still need to finish shaping the body, so I’m not going to pilot drill for the pickguard mounting screws yet. I might need to resize the pickguard depending on the the final edge radius. Telecasters have only a 1/8″ radius, but Jazzmasters have a huge round-over. It’s going to have belly- and arm-relief contours like a Strat, just not sure about the edge radius yet.

October 30

Added to the pile of templates/jigs for the body routes. I made separate ones for each area rather than make a single one for the entire body. When routing, I found a check in the wood that almost runs the entire length of the body. I diluted some epoxy with acetone and worked it into the crack. Where the crack was too thin for that I added some super glue and let that soak in until saturated.

When fretting the neck I used StewMac’s calculator to doublecheck my template print. The calculator also provides bridge location by bridge type. Center post type bridge such as Tune-o-matics and the Jazzmaster have a centerline location of 25.562 from the nut face. I followed their recommendation to offset the bass side bridge post 1/8″.

Shaped the relief contours in the body, belly and arm. It’s been too cold to paint so I decided to give the body a quick finish of lacquer sanding sealer until I can put on the color coat. That way I can complete the setup while I’m waiting. Looks pretty decent already, almost has a Fender Butterscotch vibe. I finished the headstock and the back of the neck and with Tru-Oil, sanding on 4 wet coats from 400 up to 1500 grit, wiping off the excess and letting dry for 6 hours between coats. On the fret board I used lemon fingerboard oil.

Wiring was pretty straightforward, although I re-colored the ends of some of the many white wire runs with Sharpie to help keep all the wires sorted. The shielding was tested for continuity on both the pickguard and the cavity. The copper sheet and tape I used had conductive adhesive, so there were no continuity breaks. The cavity tape laps over the edge so it comes in contact with the pickguard to complete the shielding circuit.

The Tonerider Vintage P90s have a single shielded lead. I didn’t want to un-braid the shield to make a separate ground wire so I de-soldered that and soldered in separate hot and ground wires. To the end of the ground wires I soldered on a ground clamp that was screwed to the body, the bridge pickup in the main control cavity and the neck pickup to the rhythm circuit cavity. I also drilled a hole from the main cavity to the lower bridge thimble hole and coiled a bit of ground wire in the bottom to be in contact with the bridge. That lead got a ground clamp as well and shared the ground screw with the bridge pickup. I also added the treble bleed ceramic capacitor that came with the wiring kit to the volume pot, which helps reduce the treble roll-off when reducing the volume.

I didn’t take any photos of the wiring because I was too busy being bewitched by a dumb error- I’d switched the ground lug with the control lug on the 3-way switch and it took well into the night to figure that out.

The easiest way I found to put this all together was a little backwards. I put a few screws in the pickguard first, then dropped the pickups into position and screwed those down. Then I removed the pickguard and soldered the pickup leads and screwed the pickup, volume, and bridge ground wires to the body (2 separate screws, one in the lower control cavity and one in the upper control cavity). I soldered wires to the jack last. This allowed me to leave enough wire on the pickups & jack to be able to unscrew the pickguard and flip it over for repairs/maintenance.

I like the way it plays. I kept the neck a little fatter at the 1st fret like a vintage Fender. I prefer it to my Squire, which suddenly feels a little too thin by comparison. The angled neck seat worked out well, the bridge height allows for decent string break angle to the tailpiece so I’m not getting any bridge rattle or buzz. I do need to shim the pickups up a little, I didn’t take the angled neck into account when routing the cavities and the pickup mounting screws are barely hanging onto anything. I may make the neck pocket a little deeper as well. . Also I’m not wild about the lower switch position, I keep hitting it while strumming. But the pot placement is great for volume and tone swells, and I left room on the pickguard in case I want to add another volume knob for split pickup control.

I tried the bridge with the intonation screws facing each way, towards the pickup and away. There didn’t seem to be much difference so I just set it like a typical offset guitar with the screws facing the tailpiece. I did replace the domed screws on the tremolo tail piece with countersunk screws.

The rhythm circuit is interesting. The dark sound can be useful for getting some flabby distorted shoegaze tones. It still sounds pretty lively through the Orange Two-Stroke pedal.

The Tonerider Alnico II P90s are a great match for the 1 Meg pots, and sound great with the Jazzmaster circuit as designed. The P90s have a wide range of tonal adjustments, have a nice growl, and are noise cancelling when in both are selected.

Then only thing I don’t like about the circuit is the linear taper volume pot that was included with wiring kit, it’s too fiddly when changing volume or doing swells. I’ll probably replace that with an audio taper pot.

November 6

The bridge is driving me a little crazy. Suddenly I’m getting some buzzing. I trimmed the intonation screws, thread-locked the saddle height adjustment screws, and still have some intermittent rattle*. Worse though is the string spacing, it’s oddly wide at 55mm, considering the tailpiece and the neck width, and the strings drift across the ‘all-thread’ face of the saddles. I decided to make new saddles using the design from the Staytrem aftermarket bridge. I was going to buy some from them, buy the lead time is 4-6 weeks.

I used the neck radius to size the saddles so they won’t need height adjustment screws, the diameters of the saddles themselves follow the neck radius. I had enough .5″ stainless steel rod on hand to turn all the saddles. I reduced the center diameter on each by 0.03″ so only the outside rims of each saddle would bear on the bridge. I turned a small groove in the center of each saddle with a thread cutting tool for the string slot. A overall saddle width of 0.41″ allowed for an overall string spacing of 2.05″, which fits a Tele-sized neck much better. My mini lathe has a tendency to slightly dome the centers of stainless parts when making facing cuts, so I cut a shallow relief at the center of each saddle so the saddles would stack properly and not wobble against each other. The collet chuck really helped simplify these operations, I could face and relieve each end of each saddle after they were parted off.

I drilled and tapped for the screw thread in each saddle off-center. A small flat needs to cut first with a end mill otherwise the center bit won’t bite in, but the endmill leaves a nice little flat countersunk seat for the screw spring. After that, I started the pilot hole with center bit, then drilled the pilot hole, then tapped it for the 4-40 screw. Due to the difficulty in relocating the flat spot, I did all the operations for each saddle before removing it from the mill vise.

Obviously the old holes for the intonations screws can’t be reused, but the bridge can be flipped and re-drilled for a series of new holes 0.41″ on center. Since the saddle diameters follow the neck radius, the holes are drill on a straight line about 1/16″ above the bridge floor.

The new bridge is much better, no rattle or buzz, the string spacing is right on, and the strings don’t jump out of the slots. Technically speaking the radius is off a few thousandths off at the A and B strings, but they can always be adjusted by filing down the saddle grooves slightly. The bridge is also more comfortable for palm muting, no screws sticking out from the tops of the saddles. Kudos to Staytrem for the great redesign. Considering the amount of work this took, their price is a bargain. It also includes the saddles and bridge, and is a drop in replacement on Jazzmasters and Jaguars.

*Turns out the bridge rattle wasn’t the bridge at all, but a loose screw on a locking machine head. The buzz showed up on the G string with the new bridge, and I was finally able to track it down to a locking screw that had worked loose. Oh well. The saddles were worth making for the better string spacing if nothing else.

Still trying to decide on the final color. Thinking a deep blue stain burst, the new pickguard has a blue tint to it. Anyway, the final finish won’t happen until spring at the soonest.

May 11

Finally warmed up enough to finish. Tinted nitrocellulose lacquer with some TransTint blue (8 coats), then 12 clear lacquer topcoats. I waited 3 weeks to wet sand and hand buff. Not bad for my first high gloss guitar, especially without a buffing wheel.