Refretting a ruined fretboard -- Adventures with CA

[Mark Wybierala]

Just sharing an experiment. I should have done pictures

My shop recently acquired an older Yamaha electric bass that according to a little research on Ebay is worth a little bit more money than usual. It looked okay so the front desk bought it from a customer thinking it probably only needed some setup work. It came to my attention because it had fretbuzz above the 14th fret. It clearly wasn't scrutinized by the person who purchased it.

What I discovered was that someone had performed some sort of barbaric work on the frets. Maybe pulled the frets for a refret and then changed their mind. Really odd. You could see extensive tear-out of the rosewood along the sides of every fret. There were a few frets that had obviously been reinstalled in the wrong position. At least a third of the frets could be removed using only my fingernail.

At best, a good example of this bass might be worth $800.

The rosewood fretboard was a dark chocolate color. Typical expected work from my position in the shop would be to spend maybe one to one-and-a half hours on such an instrument. But the bottom line was that the bass was unsellable. I pulled out all the frets and found that the slots were nearly all severely damaged as if someone had employed a very innappropriate device to clean out the slots. I cannot imagine what was used but it was a mess. Some slots had cavernous damage of more than .100 in width with chunks missing at the fretboard edge.

The bass was a write off so what the hell.

I started by individually repairing those tear-outs where the damaged rosewood chips were still semi attached to the rosewood. Water thin CA, a toothpick, pressing the chip back into place and wicking the CA by the smallest measure into the fracture. For the most part, this went well and I let it cure overnight using no accelerator. I then used 320 grit with a backing block to lightly remove any of the remaining elevations. I then inspected the level of the entire fretboard and the functional action of the trussrod using a full length precision straightedge. I taped off the ends of the fretslots and the edge of the fretboard and flooded the slots with water-thin CA to just slightly past the point that the open grain within the slots would absorb the CA. ...apply, watch it suck up, apply more until it puddled. I let this cure overnight. This was to address any fracturing that remained. I then used a .020 nut slot saw with a depth limiting strip to clean the bottom of the slot.

The fretboard still looked like a mess with these random excessively wide slots. I used black medium viscosity CA (from stewmac) applied with a toothpick in every gouge and at the edges of the damaged slots. It was very tedious. I employed accelerator but was very careful to not make the layer of CA too thick to cause "wet bubbles". I would maybe do three applications in one day, let the CA fully cure overnight, relevel the surface with 320 grit and a backing block and clean out the fretslot with my .020 nutslot saw the next day. Over the period of four days I repeated this process and eventually got the slots looking more like they should. It would look awful at the end of each day but look a lot better when I leveled the surface and cleaned the slot.

On the fifth day I used my fretslot saw and cut the slots to .023. I could have used my slotting miter box but I didn't. In some instances, both sides of the slot was nothing but black CA. The original frets were .095 wide but I had some .115 fretwire that I though would yield a better result.

I over radioused my lengths of fretwire and cut each fret individually. I used my dremel with a carbide wheel to cut back the tang just below the surface at the fretboard edge (tedious). My fear was that the hard rigid CA would fracture when the fret was hammered into the slot but this did not happen. The frets all seated very well.

I put the neck sideways into my vise and dripped water-thin CA into the end of the fretslot and ran a pass of accelerator down the length. I flipped over the neck and repeated this on the other side. I then applied a drop of the black CA to the end of the fretslot. In most cases, the black CA didn't wick any more into the slot and in those cases where it did, I reapplied.

This is where I'm at right now. The fret are in and they are secure. The face of the fretboard looks very good. The wide .115 frets cover the massive quantity of black CA that was used. There is at least 3/4s of an ounch of black CA in this fretboard -- a new personal record. For small dings and cracks on the surface, the black CA is almost invisible. The thin CA that I applied initially should have addressed any internal fractures in the structure and maybe it compliments the integrity of the black CA that was used as a filler. The wicking of thin CA into the fret slot ends after the frets were hammered in ought to fill any remaining voids or fractures in the black CA from the hammering of the frets. Now its a matter of cutting down the fretends with a file and dressing the ends and then leveling/recrowning/polishing the frets.

[Barry Daniels]

Wow. Would it have been less work to replace the fretboard?

[David Rickard]

I agree less work and less cost

[Mark Wybierala]

Aw.... You miss the point and.... there is the risk/reward factor. The job was done without the employment of skills. Profitability of the work was never an issue. More to the goal was to see how much superglue I could get into the fretboard. Its unlikely that I'll ever encounter such a mess of destroyed fretslots. Actually, I don't know what the goal was. Hmm. Black CA is awesome

[Brian Evans]

It will be a test of can CA glue alone hold frets reliably. CA glue, on it's own, is kind of fragile and has little shear strength. Possibly not a first choice for holding frets in place. I've glued in strips of wood to fill fret slots before, and re-cut.

[Mark Wybierala]

Agreed.