Two years ago, my son's Meinl cajon (box drum) suffered a broken string. The string in a cajon functions like the springs on a snare drum, so when broken the drum retains its boxy "thud" but the higher-pitched "snap" is lost or, worse, turns into a sloppy rattle. So I decided to try to replace the string (which is essentially just a wound guitar string) myself.
I removed the face of the cajon easily enough — it is secured by just a handful of wood screws and some adhesive tape. But once inside, I decided I wasn't satisfied with the manufacturer's approach to securing the string. Guitar strings have a "ball end" that secures that one end, but the other end was secured by putting a half knot in the string. I wanted something less prone to tension changes and to inconsistencies in the precision of those knots across the two strings.
My solution was to hit the hardware store for a couple of T-nuts, which I installed on the underside of the top bit of framing on the cajon. These would provide a way to secure the string with the tension of the T-nut's associated screw (much like the way electrical wiring its secured at switches). I drilled an additional hole on each side for the string to pass through so that it would approach the T-nut from the side instead of from the top. Then, I loosened the tension bar on the bottom of the drum and rewired it, pulling the strings taut with a single wrap around the T-nut screw before tightening that down.
Once the strings were secured, it was trivial business to screw the drum face back on and then use the drum's tension bar system to further tighten up the strings to my son's preferred tone.
Why recall this two-year-old tale today? Because during our church worship service this past week, my son suffered another broken cajon string. But replacing it this time around was super easy, in part because of the hacks made to the drum the last time. And who knows — maybe somebody else out there is looking for just this sort of improvement to their own cajon? If so, consider our approach as one possibility that might work for you.
