Help Determining String Spacing on Custom Bass

Discussion in 'Luthier's Corner' started by Medici, Nov 8, 2019.

  1. I've picked up a beautiful bass neck + body that needs some building up. Everything except the wooden bits, and I mean literally everything. How on earth am I to determine proper string spacing at the bridge and over my pickups with no tuners or bridge? It's a 5-string (soon to be fretless) bass with a nut width of 45 mm and is a 34" scale. I haven't the slightest clue as to the math or procedures necessary to determine proper string spacing. The pickup routs are quite large (109 mm x 32.5 mm) and they are both the same size (neck and bridge). I have paired this with a set of bartolini P25CBC pickups. I would love to be able to use something like a Hipshot KickAss bridge but would like to be sure that's within the realm of possibility depending on what proper string spacing I end up requiring. I am willing and able to provide any and all dimensions I may need. Thanks in advance for your help.
  2. Beej


    Feb 10, 2007
    Vancouver Island
    You can figure out the range of what would work by doing some measuring while the neck is mounted to the body. I'd do it like this:

    Measure from the fretboard edge of the nut to 34" on body, lay a piece of masking tape and mark 34".
    Lay a long ruler (or a straightedge of some kind) along the side of the neck and draw a line across the masking tape crossing the 34" line. Repeat on the other side of the neck.

    The distance between those lines is the distance of the string fretboard spacing (extrapolated to the bridge point). You can then determine what range of string spacing the bridge will need to be within to work.

    The 5 string Kickass is adjustable from 17-19mm spacing. Overall that's a range of 68-76mm (2.67-3"). As long as your line is far enough apart to accommodate 68mm with 3-5mm on either side, you should be good to go. :thumbsup:

    Sorry about the detail... I foolishly drank a coffee after 5pm :woot:
  3. What Beej said. Use the instrument to, basically, draw out a full size pattern. He mentions it in his explanation but don’t forget to keep the string lines slightly inside the edge of the board. Basically, where you would want the strings to actually be when strung up.
    Beej likes this.
  4. I'm unfamiliar with soapbar pickups and even more so with bartolinis, is there a recommended string spacing for those pickups or are the poles a straight line i.e wouldn't really matter? If there's any documentation on it I can't find it, bartolinis seem to be a bit of a mystery in that regard. Thanks again for the replies Beej and Matt, btw.
    Beej likes this.
  5. dwizum


    Dec 21, 2018
    I can't answer for that bart particularly but I can say, you should drop them an email and ask. Their tech staff is very responsive and helpful.
  6. I measured it out to be a little over 73 mm so I think it should work out. Also haven't ever had a build where I felt it was worth it to spend any reasonable amount of money on bridge/tuners but I think cheaping out on them will only come back to haunt me, so I'm going full hipshot. I'll try and put together a collection of pictures while I piece it together and show them once I'm finished because I'm pretty excited for this.
    Matt Liebenau and Beej like this.