Defretting a bass guitar

I have been playing bass guitar 29 years, and for almost that entire time I’ve been an exclusively fretless player. I first defretted my bass in 1998, after only playing for five years. I remember that ordeal quite well: I yanked the frets out of my Peavey B-Quad, and filled the slots in with bondo, sanded it smooth and called it a day. It was pretty ugly and crude, but I considered it functional at the time and it introduced me to the fretless life. Since then, my defretting technique has improved considerably (and I’d like to think that my intonation has gotten modestly better as well). Recently I was asked to defret a Fender Jazz bass, and I thought that I’d take the time to explain my current defretting technique.

The Fender Jazz bass is kind of the defacto fretless machine, thanks to Jaco’s outside influence (although I am partial to Mick Karn, myself). The frets on this particular Jazz bass were grody to the max, and were just begging to be pulled out:

The trick to removing frets is mitigating damage to the fretboard. Fretboards have a tendency to chip as frets are removed, and is time consuming to fix, so preventing that from happening in the first stage is paramount. Typically I will over-tighten the truss rod, forcing the neck into back-bow, which will cause the fret slots to relax ever so slightly. I will also condition the fretboard, so that it isn’t so dry and will be less prone to cracking. Then I will apply heat to each fret with a soldering iron, which will help soften the glue and release the wood’s natural oils and help the fret to pull out without incident. Using the right tool here is also important: I don’t remember what I used on my first bass, but these days I’m using some small end nippers, ground down flat so they get up underneath the fret.

I’ve gotten pretty good at this over the years, so I didn’t need to fix any fretboard chip out (this time). The next step was to prepare the fret slots for this fills, so I cleaned them out with a dremel tool attached to a fixed base. This clears out any glue, wood, and detritus from the fret slot, while also ensuring a uniform depth.

For wood fretboards, I opt to fill the fret slots with a wood veneer. Most people prefer a visible line, so in this case I used maple to fill the slots. I prefer using wood rather than plastic, as the plastic can wear down at a different rate as the fingerboard, and will just start feeling weird.

Installing fret lines requires some finesse and attention to detail. Some fret slots are curved on the bottom, matching the fingerboard’s radius. So each maple fret line has to be cut to fit. A radius gauge and a razor blade does the trick.

I use wood glue to install the maple lines. This creates a much stronger bond than superglue, and it allows for some working time to seat the maple into the slot properly.

Now the fun part: cutting the maple lines down. I start with a super sharp chisel, and once I get them close to the board, I flood the maple with thin superglue, which fills the pores and prevents rosewood dust from getting into them and obscuring the line. Then I knock the high spots down with a flat sanding block.

Now, the most important part: leveling the board. This is absolutely crucial to get right – if the board isn’t perfectly level, there will be notes that won’t speak properly. The key to a good sounding fretless is optimizing the “mwah” sound, and to get that sound the strings need to be close to the fretboard. The lower the action, the more critical it is that the board is absolutely perfect – even a slight variance interfere with the strings oscillation and make notes sound weird. We utilize our PLEK machine to level our fretboards, both for fretless instruments and also during the refretting process. This levels the boards to our specifications, and cuts the radius and builds in the perfect amount of relief with an accuracy of .01mm.

All hail our robot overlord!

Once the instrument has gone through the PLEK process, it requires some smoothing of the fretboard to remove the machining marks. This is where a skilled tech comes in – it requires lots of experience and technique to sand the board smooth and not compromise the PLEK quality. There is a common misconception that the PLEK machine does all the work, but it’s merely a tool for an experienced guitar tech to wield.

We sand our fretless boards smooth from 300 grit all the way up to 1000 grit sandpaper, utilizing a flat block. This makes the board feel ultra smooth and a joy to play.

That’s it – no more frets! Once the defretting is complete, the neck goes back on the body for a new bone nut and setup. This Jazz bass plays way better than my Peavey B-Quad did when I first yanked the frets out over 20 years ago. But nobody comes out of the womb knowing everything, and practice makes perfect… except maybe for my intonation, which still needs work…

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