1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

4 String Shorty

Discussion in 'Luthier's Corner' started by dblbass, Jan 15, 2017.

  1. dblbass

    dblbass Commercial User

    Mar 24, 2007
    Beacon, NY
    Owner of MBJ guitars, Maker of fine sawdust for Carl Thompson Guitars
    Hey LC,

    Decided to do my first build thread while I work on my new project. I've been building for a while, but never really documented the whole job before. This bass will be pretty simple, but I'm trying a few new things, so it should keep things fun and interesting.

    Here's the specs:

    4 String
    32" scale
    Swamp Ash body
    Mahogany neck
    Ebony fingerboard
    Hipshot Ultralites
    Hipshot A style bridge

    What I'm not sure about:

    Still trying to decide what kind of electronics I want in this bass. My go to is a Kent Armstrong MM pickup run passive. Kent's MM pickup is one of my favorites, but I've been using them a lot recently and might try out something different. Other options are to add his 2 band pre amp. Or go a whole different route and use aguilar DCBs with one of their pre amps. I've also really enjoyed the EMG EXB control that I used in a few of my instruments. It's a single knob preamp (love the simplicity), but it's a little noisy in my experience. I have some time before I need to decide which I'm gunna use, so for now it'll stay a mystery.

    The body will be the same shape as the one below.


    I'm using a relatively new neck design (for me!) on this build too. I'll be using a 1 piece neck instead of a tilt back headstock with a scarf joint. I put the truss rod in a little differently than many builders, so it took some planning, but the end result worked out really nicely.

    I'm looking forward to getting this thread going! I've already got the neck started, so this should move right along.

    Last edited: Jan 15, 2017
  2. GKon

    GKon Supporting Member, Boom-Chicka-Boom

    Feb 17, 2013
    Albuquerque, NM
    I really like that body design and control cavity cover.
    Looking forward to,seeing more!
  3. dblbass

    dblbass Commercial User

    Mar 24, 2007
    Beacon, NY
    Owner of MBJ guitars, Maker of fine sawdust for Carl Thompson Guitars
    I always start off with the neck. You can only go so far on the body without it, so I like to get it done first. This bass will have a 1 piece mahogany neck with an ebony fingerboard. The truss rod will be a single action rod, but I put it in a bit differently. I'll go into detail below and in the next few posts.

    Here's some shots of the wood before I get started. I get the fingerboard pre scaled and radiused (16") cause it's a huge time saver. I get the neck blank totally squared up to 1x4x36ish so I have a nice starting point.


    Step one is getting a nice centerline down the entire neck blank and drawing the shape of the neck out on it. I mark specific areas on the sides of the neck to let me know where the nut starts and stops and where certain transitions will go on the headstock and the back of the neck. Then I drill and 3/8" hole for the truss rod anchor part of the way through the neck.


    The truss rod is just a simple 3/16" round piece of steel with a stew mac anchor on one side and a spoke wheel on the other. I put shrink tubing over it to keep it free to move in the channel.

    I route a channel down the center of the neck 1/4" wide and 5/8" deep starting at the hole for the anchor until about 3/4" away from the heel.


    Next I rough cut the shape of the neck on my bandsaw and trim it flush with a router and the acrylic templates I made. I also mark out where the tuners will go and drill pilot holes followed by a 9/16" hole for the Hipshot ultralites.


    This things is starting to look like a neck!
    GKon, Matt Liebenau and reverendrally like this.
  4. Very CT, I like!
  5. dblbass

    dblbass Commercial User

    Mar 24, 2007
    Beacon, NY
    Owner of MBJ guitars, Maker of fine sawdust for Carl Thompson Guitars
    Makes a lot of sense. I work with Carl!
    I-Am-The-Slime likes this.
  6. dblbass

    dblbass Commercial User

    Mar 24, 2007
    Beacon, NY
    Owner of MBJ guitars, Maker of fine sawdust for Carl Thompson Guitars
    Now its time to dimension the neck a little further. I take 1/4" off the top of the headstock and 3/16" off the back of the neck with a router. Its not super clean, so I'll hit it with a block and some 80 grit paper to tidy it up. I leave a bit of extra wood around the transitions that'll be hand carved away later. QjSNUKf.

    This next step is a bit out of order... I drill a 1/2" hole for the truss rod at the heel of the neck. This gives me plenty of space for the spoke wheel adjusters as well as the washers I use. I have a very scientific approach to this as you can tell from the pictures....

    Basically its just a block with a half inch hole drilled in it that I use as a follower for the neck. I clamp it down and double sided tape it to the neck so it wont move. Then I say a quick prayer and start drilling!


    This method sucks...So if anyone has a better idea, I'm all ears!

    Now it's time to glue the truss rod in. It's a single action rod (wrapped in a little shrink tubing) that gets put into the channel straight. I know this is a bit different than most single action rods go in, but trust me!! It'll make a little more sense in the next few steps. I learned this design from my mainest man Carl Thompson. I changed things around a little (he puts them in with the truss rod adjustment on the headstock), but it essentially works the same way. I really like the design, but the time I spent working at Sadowsky turned me on to spoke wheel adjusters. I love that in a pinch you can adjust the neck with just about anything. This is the second bass I'm trying this on, so I'm not totally sold yet, but I'm thinking its the way to go on my less fancy necks.

    I make a 1/4" chock to fit the slot and glue the truss rod in place.


    After I let it dry overnight, I drip a little epoxy over the slug to fill in the space and lock it in a little more. Once dry, I taper the surface of the neck. This is what makes the truss rod work. The neck is 1/8" thicker at the heel compared to the nut. So the truss rod is the same distance from the back of the neck the whole way down, but its at an angle to the top of the neck.

    I do this using a router jig I built.


    The rod works great and is a little simpler to install imo. I clean this up with a nice flat block with some 80 grit.
    afa3 and GKon like this.
  7. dblbass

    dblbass Commercial User

    Mar 24, 2007
    Beacon, NY
    Owner of MBJ guitars, Maker of fine sawdust for Carl Thompson Guitars
    Got the fingerboard and the body blank glued up. I trim the fingerboard to the neck with a flush cut bit and finish off by sanding the sides with my fingerboard leveling beam to ensure it is square and perfectly straight. mu9247p.


    At this point I figured I'd do the main part of the logo since the headstock hasn't been sanded flat yet anyway.


    Once the body dried overnight, I run it through the thickness sander to clean it up to 1 3/8". I draw on the body shape and cut it out on the bandsaw.



    To finish up for the day, I routed the neck pocket. I make a simple jig out of 3 pieces of straight wood to frame the neck out. I line it up straight to the centerline and double sided tape the blocks in place. Then I just remove the neck and I have a perfect neck pocket. The pics below are from a previous build.


    That's it for now. The next few steps are a lot of hand work.
  8. dblbass

    dblbass Commercial User

    Mar 24, 2007
    Beacon, NY
    Owner of MBJ guitars, Maker of fine sawdust for Carl Thompson Guitars
    Got a bunch done in the last week. First, the transitions were carved on the neck and the nut slot was routed and then flattened out. I draw a bunch of reference lines on the neck before I carve. I like to carve flat surfaces first and then round it all out once I have the basic shape. Here's a pic of those lines. Fi2XuQx.

    Once its all carved, I check to make sure the truss rod is operating smoothly and that the neck wood hasn't moved weirdly.


    All the routes are done on the body before carving. I originally went with a plain MM pickup, but added a wooden cover after. Here's a shot of the body all routed before the wooden cover was done. I draw the carving lines out on the bass so I have a reference while I work. 0BZgn8S.

    Here's a shot of the tools I use to carve the bodies. Hand carving these allows me to shape the bass in really interesting ways. I can fade in and out of hard lines and bubbly sections and stretch things out to make it more ergonomic.


    And after the carving and redoing the pickup and pickup route.


    Before the new pickup route was done.


    And the back.


    And now we sand! This body shape and the wood texture make it a little tough, especially with a natural finish. Hand carving the bass is fun, but it makes sanding it a little harder because the geometry is pretty wacky.

    I start with the neck though....cause its easy! Already got the first coat of Danish oil on it.


    I'll have the body sanded this weekend if the snow storm ever lets up!

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.