TOOL
Clamps
Enough of them, and enough reach.
| Deep-throat C | 150 – 300 mm throat for body work |
|---|---|
| Spool clamps | Timber spools with a bolt; gentle on the box |
| Cam clamps | Fast, light, one-handed |
| Spring clamps | Light duty, for holding cauls and templates |
| Cauls | Softwood or cork pads to spread pressure |
| Count | 30 or more is a realistic starting point |
| Pressure | Firm and even; enough to close the joint, not to starve it |
|---|---|
| Cauls | Always use a caul against a soft or finished surface |
| Order | Work from the centre outwards on a large joint |
| Cure time | Full clamp time; do not release early to check |
| Alignment | Check for drift while the glue is still open |
| Price band | Moderate, and it adds up |
A guitar has more glue joints than most furniture, and each one needs pressure held for long enough to cure. Deep-throat C-clamps reach across the body, spool clamps hold the top and back to the sides, and cam clamps are fast enough to work around a full perimeter.
The most common mistake is not owning enough. A box glue-up takes twenty to thirty clamps at once, and improvising with too few is how a joint ends up starved or open.
At this stage
Clamps are used at every assembly step. Laying them out ready before the glue is opened is the difference between a clean glue-up and a panic.
Suits these instruments
- All guitars
Works with
- Glue
- Go-bar deck
- Body mold
- Radius dish
- A clamp under load can slip and spring. Keep fingers clear of the jaws and do not over-tighten a small clamp.
- A bar clamp that is not supported can drop a body onto the floor. Support the work as well as clamping it.
Working notes
- Lay out every clamp before you open the glue bottle.
- Use cauls against spruce and cedar so the clamp does not dent the plate.
- Wax or tape the clamp jaws so squeeze-out does not glue them to the instrument.
- Count your clamps before starting. Running out mid-glue-up is not recoverable.
Related
Nitrocellulose lacquer
The traditional finish: thin, clear, and easy to repair.
French polish
A shellac film applied by hand, one thin layer at a time.
Sanding sealer
The first coat that stops the wood drinking the finish.
Glue
Three glues, three jobs, and none of them interchangeable.