Sunday, September 1, 2013

Building a Bass Guitar Kit, Part 1

Although I play a Fender Jazz bass, I've always been curious as to how the Precision bass sounds and feels, especially with its wider neck.  Normally, one would just go to the local guitar store and try out one of their many basses.

The problem is, I'm left-handed.  This makes test driving a P bass almost impossible: of the three guitar stores in my area, not one had a lefty P bass (if they had any left-handed basses at all!).

So, if I wanted to try a P bass, I pretty much had to purchase it, sight unseen.  And without the chance to play a bass first, I didn't want to spend too much money on something that I might find clunky and awkward to play.

During my search for an inexpensive P bass I came across a P bass guitar kit.  And I thought, "Why not?"  I could paint it a color I liked (rather than being left to the limited color selection of most left-handed guitars).  And as for the assembly, well, how hard could it be?

The kit was ordered from Canada, and after a bit of a wait, it arrived:

Christmas in July

First things first.  After inventorying the parts (discovering a few minor discrepancies) I started assembling it.

The body and neck both needed sanding -- I believe they were coated with Polyurethane, but the surface of both the body and neck was very rough, and the kit supplier recommends that they first be sanded down (starting with 180 grit, then 240, and finishing off with 320).

Also, you need to drill 17 holes:  4 holes for the mounting screws for each of the four tuners, and 1 hole for mounting the string tree.  All in all, not terribly difficult.

Here's how it looked when fully assembled.  Not bad!

It played well enough that I decided to continue with the project.  But before painting the body (which would be the lion share of effort and additional cost), I first needed to tackle some of the issues I found during the assembly process.  Specifically:
    1.  Parts Discrepancies:
    • No Allen-head Wrench (for truss rod adjustment).
    • Springs instead of compression foam pad for pickup height adjustment.
    I contacted the kit supplier and they sent me an Allen-head wrench to replace the missing one.  The springs versus pads were no big deal, and probably due to old documentation.

    2.  Wrong nut:  it looked like a right-handed bass nut hand been flipped around and installed in the neck.  This would be fine if the string channels were flat, but they weren't.  They were cut to slope towards the tuners when the nut was installed in a right-handed guitar.  The problem was:  in a left-handed guitar, they sloped in the the opposite direction, not towards the tuners, but toward the bridge.

    I contacted the kit supplier, and, although they didn't have any nuts for lefty basses, they did send me a nut blank.  Not sure if I wanted to try cutting nut slots, I also looked around on the internet and found an Allparts nut listed on Ebay with the correct width and a flat base.  It was this nut that I installed.

    Let me add -- the kit supplier was very willing to work with me to resolve the nut and the missing Allen-head wrench issue.  The other problems (listed below) were more problematic, because they weren't the fault of the kit supplier.  Instead, I believe they are due to lack-of-attention at the manufacturer (China, I believe).

    3.  Obscured fret dots.  Not a big issue.  But required some cleanup.

    (Click on image to view in its entirety)

    4.  Bridge Mounting Holes:  Angled and various depths (illustrated below with small dowels in the holes).  Not a big deal, just sloppiness on the part of the manufacturer.


    5.  Rear strap button hole:  not centered and drilled at an angle.


    This was more of an issue with me, so I:
    • Drilled it to make the hole slightly larger and then pressed-fit a wooden dowel into it.
    • Counter sunk the dowel.
    • Filled the counter-sunk cavity with Bondo.
    • When the Bondo dried, sanded it flat.
    • Then drilled the correct hole.
    Note:  Bondo is great for patching small holes and dents in the body.

    6.  Incorrect Wiring:  The bass had Jazz bass wiring (in which the pickup was connected to the wiper of the volume pot), rather than Precision bass wiring (in which the audio jack is connected to the wiper of the volume pot).  I fixed the wiring to be P bass wiring, per the photo below (note the paint job!).
     

    7.  The through-body holes for the four neck screws were too narrow.  This meant that, when screwing in the four screws to attach to the neck to the body, these screws were also cutting threads in the body wood, not just the neck wood.  Threads in the body wood prevents the neck from being sufficiently tightened to the body -- the screws snug up to the body first, rather than pulling the neck in as tight as it can go.

    The obvious fix is to widen the diameter of these four body holes so that the screws would pass freely through the body.  I used a 13/64 drill bit.

    8.  Fret Buzz when fretting either the E or A string at the 8th fret.  The 9th fret was noticeably higher than the 8th.  I tapped it down with a rubber-headed hammer, and this fixed that problem.  Buzz fixed!

    But with that fret now lowered, I quickly discovered other frets buzzing.

    Oh boy!  My chance to learn how to level frets! (Said with a distinct lack of enthusiasm).

    Still, why not?

    So I purchased a fret rocker and got to work, but I quickly discovered that the fret leveling issues where more significant than I imagined (or, more likely, I was making them worse by attacking them one fret at a time), and I needed to open up the wallet and add to the arsenal.  Here's my fret-leveling kit now...

    (Click on image to view in its entirety)

    Clockwise, from left:
    • Micro-mesh polishing pads for polishing the frets after they've been leveled and crowned.
    • Bass Guitar Neck Straight Edge (to ensure that the neck is flat and level *before* you start leveling frets).  Stewart MacDonald carries these, but I purchased mine from Ebay.
    • Brass brush (for cleaning files).
    • Fret File (for crowning the frets -- I purchased the Medium/Wide Double-edge Fret File from Stewart-MacDonald).
    • 320 grit sandpaper with adhesive backing (Stikit Gold Paper Self-adhesive Abrasive -- purchased from Steward MacDonald).  This is for the next item:
    • Fret/Fingerboard Leveler, 8 inch.  Stewart MacDonald carries these, but I purchased mine from Ebay.
    • Fret Rocker.  Another Ebay purchase.
    • Sharpie Pen.
    (Not shown is the masking tape used to protect the fretboard during leveling/crowning).

    When using the Fret Leveler it is important that you first adjust the truss rod so that the neck is flat.  And do this before you tape up the fret board.

    Stewart-MacDonald has a good video on using a Fret Leveler:


       
    Here's a picture of my Fret Leveler beam in action (again:  first adjust the truss rod to ensure that the neck is flat!!!).  No need to be aggressive when using it-- the weight of the beam itself is enough to sand down the frets.

    (Click on image to view in its entirety)

    Before I started leveling I first marked the tops of all of the frets with the black Sharpie pen.  As I leveled, the leveler removed the black markings from the high frets, and the low frets were yet be touched.  Below is an example of the different fret heights.  Note the areas that are still black.  The neighboring frets are still too high and must be leveled further.

    (Click on image to view in its entirety)
     

    Here are a couple of other fret-leveling YouTube videos that I found interesting, especially if you only need to level a fret or two.  If you search YouTube, there are more!

    Leveling inexpensively:    

    I like this guy's approach:  

    Some additional notes:
    • When crowning the frets after leveling, again mark the fret tops with the black Sharpie.  When you finish crowning a fret, there should only be a thin black stripe left running along the fret's top.  You may want to practice your crowning technique on the high frets (e.g. 20th) first.
    • If you need to dress the ends of the frets, you'll need an appropriate file to do this.  Fortunately, the fret ends were fine on this neck -- no protruding sharp edges.

    9.  Anemic and twangy sound when played.  I first thought this might be the pickups, but decided to try a different set of strings first.  Glad I did -- the difference was night and day.  It needs proper strings!
    OK, those problems were fixed.  Now on to painting and finishing!

    Finishing the Neck:

    I decided on a clear satin Polyurethane finish.  The local hardware store had a can of exactly what I needed:



    Fret board taped off, a thin coat of Poly applied with a cloth, and now to the drying...





    After the polyurethane dried, I sanded it smooth with a very fine grit sandpaper to make the neck smooth and fast.


    Disclaimer:

    This was my first time doing any of this:  fret leveling, painting, etc.  Before you tackle your own project, do your research!  Don't depend solely upon my experiences.


    Next installment:  Painting the body! (Click here!)



    Links to Bass posts of mine...

    Sonic Blue Bass (part 1 of a 3 part series)

    Mellow Yellow Bass

    Short-scale Telecaster Bass

    Bass Guitar Painting Jig

    Repairing a G&L Butterscotch Blonde Paint Chip

    G&L ASAT Bass Strap-button Extender

    2 comments:

    SOLO Music Gear said...

    Thank you for another insightful article. Where else might someone obtain that kind of knowledge written in such a professional manner? I have a presentation coming up next week, and I'm looking for relevant information about Build Your Own Bass Guitar.

    Jeff said...

    Thanks for your comment.

    For additional build examples, try the TalkBass forum (you might need to google it to find it). I haven't been on the site for years, but, as I recall, it had a number of projects posted by builders. Maybe there are links to the sites (or blogs) of others.

    Best regards,

    - Jeff