Which clamps should I buy first?

Clamps are the tool people buy last and then wish they had bought first, because almost every job goes better when the work is held still and you have both hands.

Safety

Step by step

1. Buy F-clamps as the core.A sliding bar with a screw head. Real, adjustable pressure, good depth of reach, and inexpensive. Four of about 300mm handles most household work and it is the right first purchase.
2. Add quick-grip trigger clamps for convenience.One-handed operation, so you can hold a piece in place and clamp it. Much less pressure than an F-clamp, so they are for positioning rather than for glue-ups.
3. Match the pressure to the job.Glue-ups need real pressure to close a joint. Holding a workpiece to a bench does not. Using a light clamp for a glue-up gives a weak joint that looks fine.
4. Do not overtighten.Excessive pressure squeezes glue out of a joint and starves it, which makes it weaker rather than stronger. Firm, even, enough to close the joint.
5. Use cauls or scrap to protect the work.Offcuts between the jaws and the workpiece spread the pressure and prevent dents. Most clamps have small pads that mark soft timber badly.
6. Get sash or bar clamps only if you build things.Long clamps for door frames, table tops and carcasses. Expensive and bulky, and unnecessary for repairs and fitting. Pipe clamps on your own lengths of pipe are the cheap way in.
7. Consider spring clamps for light holding.Very cheap, one-handed, almost no pressure. Good for holding a template, a cloth or a trim while adhesive grabs. Not for anything structural.
8. Add a corner clamp for right angles.Holds two pieces at 90 degrees while you fix them. Genuinely useful for boxes, frames and any butt joint, and awkward to improvise.
9. Consider a vice or a portable workbench instead.For many jobs the answer is not more clamps but somewhere to hold the work. A folding workbench with jaws does the job of several clamps.
10. Buy in pairs at minimum.Almost nothing is clamped with one. Pressure needs to be balanced across a joint or the piece twists as you tighten.
11. Check the reach as well as the opening.The throat depth determines how far in from an edge you can clamp. A clamp that opens wide but only reaches 50mm in is limited for panels.
12. Expect to want more.Every woodworker's observation is that you never have enough clamps. Buy the cheap ones in quantity and a few good ones for pressure.
13. Dry-clamp before applying glue.Assemble and clamp with no adhesive to check everything closes and you have enough clamps within reach. Discovering you are two short with glue going off is the classic error.

Tips

• Dry-clamp every glue-up first. It checks the fit, the order and whether you have enough clamps before anything is irreversible.
• Offcuts between jaw and workpiece. Clamp pads mark softwood in seconds and the dent does not come out.
• A folding workbench with jaws often replaces several clamps and costs about the same.

Common mistakes

• Overtightening a glue joint — It squeezes the adhesive out and starves the joint, which makes it weaker. Firm and even is what is wanted, not maximum force.
• Using trigger clamps for a glue-up — They apply far less pressure than an F-clamp and the joint may not fully close. Use them for positioning and F-clamps for gluing.

If it doesn't work

Questions people ask