Guitar making is a quiet, precise craft, which makes it easy to forget that it involves routers turning at twenty thousand revolutions per minute, solvents with real toxicity, dust from woods that cause occupational asthma, and strings held at sixty kilos of tension.
The injuries that actually happen in this trade cluster into four groups. All four are predictable, and all four are preventable with equipment you can buy for less than a set of tonewoods.
1. Edge tools
Chisels, gouges, knives and spokeshaves cut the hand that is holding the work. This is the most common injury in the workshop and the most avoidable.
The counter-intuitive part is that a sharp tool is safer than a blunt one. A sharp edge bites and stays where you put it; a blunt edge needs force, and force is what makes tools slip. Sharpening before every session is a safety measure, not a quality measure.
- Clamp the work. Never hold a piece in one hand while cutting with the other.
- Keep both hands behind the cutting edge, always, without exception.
- Cut away from your body. Set the work so the cut travels into free space.
- Store edge tools with the edge covered. A chisel loose in a drawer is a cut waiting to happen.
- Never chisel toward a hand that is holding the piece steady.
2. Power tools and routers
A router cutter is the most dangerous thing in a guitar workshop. It removes material faster than any hand tool, it throws chips at speed, and it grabs the work if the cut is too deep or the feed direction is wrong.
Binding channels, truss rod slots, neck profiles and pickup cavities are all router operations, so there is no way to build a guitar without one. The mitigation is shallow passes, correct feed direction, and keeping hands well clear of the cutter.
- Shallow passes. Never take a full-depth cut in one go.
- Feed against the cutter rotation — right to left on a table-mounted bit.
- Eye and hearing protection, every time. No exceptions for a "quick" cut.
- No loose clothing, no gloves near a spinning cutter, hair tied back.
- Support the work fully so it cannot tip into the cutter.
- Disconnect the power before changing a bit.
Router kickback. If a cut is too deep, the cutter grabs the work and throws it. The work leaves your hands faster than you can react, and whatever is in its path gets hit. Shallow passes are the entire defence.
3. Dust
Wood dust is a respiratory hazard, and some species are considerably worse than others. Cedar and rosewood are well-documented respiratory sensitizers that can cause occupational asthma. Ebony produces a fine dark dust that is a known irritant. Mahogany is a sensitizer. Spruce is an irritant.
Sensitization is cumulative and permanent. You can sand cedar happily for years and then develop a reaction that never goes away, after which any exposure causes breathing difficulty. There is no way to know in advance whether you are the person it happens to.
- Extraction at the source: a hose at the sander or router, not a shop vacuum in the corner.
- A P2 or P100 respirator for sanding, routing and thicknessing. A dust mask is not enough.
- A workshop air filter to catch the fine dust that extraction misses.
- Do not sweep with a brush. It puts settled dust back into the air. Vacuum or use a damp cloth.
- Change the respirator filters on schedule, not when you remember.
4. String tension
A set of six steel strings on an acoustic guitar is under roughly sixty kilos of total tension. Each individual string is holding fifteen to twenty kilos. That is a real stored energy load, and it releases all at once when a string or an anchor point fails.
Most string injuries happen during a string change or when tuning up a new string. A string that snaps at the tuning peg whips across the headstock at speed, and it will cut whatever it hits — usually the hand holding the winder, sometimes the face.
Wear eye protection when changing strings
Particularly when bringing a new string up to pitch for the first time.
Keep your face out of the line
Stand to the side of the headstock rather than directly in front of it when tuning a new string up.
Bring new strings up slowly
Tune gradually and let the string settle rather than cranking it straight to pitch.
Inspect before you tension
Check the ball end, the bridge plate, the nut slot and the tuning peg for wear before you load the string.
Replace worn hardware
A cracked bridge plate or a worn tuning peg fails under load. Replace it before it does.
Eye protection, a P2 respirator, hearing protection and a pair of thin nitrile gloves cost less than a single set of tonewoods and prevent the majority of injuries in this list.
Solvents, in one paragraph
Nitrocellulose lacquer, thinner, acetone, naphtha and methylated spirit are all flammable, all harmful to breathe, and several of them are regulated. Spray outdoors or in an extracted booth, wear an organic-vapour respirator rather than a dust mask, ventilate low as well as high because solvent vapour is heavier than air, and keep every ignition source out of the room. Read the safety data sheet for anything you open.
Every injury in this article was predictable. That is the good news: predictable hazards are the ones you can do something about.
