This is my first build. Due to increasing arthritis in my fingers I decided to try short scale and picked up a JMJ Mustang. Put on a set of TI JF324's and I'm loving it so much. It's pretty light, about 7lbs 8oz and that weight is just perfect for my old back. But the headstock on these are really thick and the tuners are heavy so it neck dives a bit. It's not much out of balance, about 5 oz. according to my water bottle test. So I put a set of ultra light tuners on and that 90% fixed it but I think if I just had an inch or two more on the upper horn it would balance better and then I could put the original lollipops back on. The other thing I don't like on the JMJ is the relicing on the body. It looks like it was done by someone following a pattern with various implements. I've always wanted to try my hand at building a bass, so why not start with just a body, and get exactly the guitar I want. The pic above is the template drawing and parts I've accumulated so far. Disclaimer: No JMJ's will be harmed in this project, I'm buying parts as I find them off Reverb and Ebay. I have a nice piece of swamp ash for the body. I'm planning on sanding the headstock down to remove the the factory relic job, then I'll stain the body and head to match in a light amber. The pick gaurd will be red tort. I ordered a blank and will be trying to make one templated off the JMJ. I'm going to be gluing up a 2x framing lumber blank and will be practicing all the operations on that. I guess that's about it. I'll be posting progress here as I go, any advise is much appreciated. Wish me luck!
Made quite a bit of progress so far...this is just the framing lumber practice body but it came out rather nice with no major problems. The neck pocket isn't quite as snug as my JMJ which you have to push pretty hard to get in, but it's a lot better than a bunch of older P-basses I've had. I think I can do better on the real body. I used the 3 boards clamped to the body method I ran into a problem with the bridge I bought, which is for a P-bass. turns out P necks are a little wider and so is the bridge saddle spacing. The JMJ bridge is 2 - 3/32 and my P bridge is 2-5/16. I really wanted to do a string through bridge cause I love my TI flats but all I could find in that width was a Schaller adjustable but it's top load only. It's really hard to find bridges for these necks! Quick question, I'm getting some round-over bit burn going around the horns. Not sure if it's because of the nature of the white pine lumber or maybe I need a better technique. Sneak up on it a little more, or maybe it won't be a problem with the swamp ash?
Small increments will help with the round over bit. If you look around here @Bruce Johnson has some good info about cleaning router bits which might be all it needs. Before you make the neck pocket tighter don’t forget the finish will add some thickness to the walls depending on what you use.
Good point about the finish on neck...I'm planning on sanding down and removing the relicing from the neck and I'll refinish it in lacquer, but I should probably do that next before I fit it. The router bit should probably just be replaced, it's kind of dark on the cutting edge.
Unless you've routed hundreds or thousands of feet of lumber it's probably not actually dull enough to need replacing. Really, just give it a good cleaning, it can make a "dull" bit like new! Great progress so far. That "practice" body looks pretty nice. Maybe you should finish it and make a second bass...
Haha...actually I'm going to offer it up free to anyone who wants it.. I'd hate to throw on the burn pile. Speaking of sanding down the neck...what's the best way to sand the back down, a radiused sanding block?
Sanding the back of the neck? I always just use a soft foam sanding pad and match the contour by curving it in my hand against the neck.
Got the neck nicely sanded down...used lacquer thinner to take the bulk of the finish off and then a light sanding on the neck back and pretty aggressive on the head-stock to remove all the relic gouging. Then I took a closer look at the p-bass bridge i had bought and realized that by drilling some new holes in the back of the bend for the saddle screws, I could flip all the saddles over and get the spacing I need. Now the problem is that the distance from the through body hole to the saddle groove is much shorter on this bridge than on the JMJ bridge, like almost 3/4". So when I string up my TI flats (which are for a 32" scale) the E string body wants to wants to wind around the post about half a turn. Would it be too weird to drill the body hole just behind the bridge bend? I could gain about .5" of length that way.
So, I'm almost done with everything and I ordered a piece of cellulose nitrate for the pickgaurd. It's .1 thick but it's kind of transparent in places and you'll be able to see the pickup routing cavities through it. I'd like to make the back opaque so I'm thinking of either trying to mount it to white vinyl adhesive paper or paint the back with alkyld white primer. Any thoughts on this?