Guide written by:
Dennis, self-taught DIYer, Bristol
An essential tool for beginners and experts alike, a clamp is used in nearly all assembly operations. Whether they are mason clamps, hand pumps, screws, or even tweezers, there’s a clamp to squeeze just about anything.
- A clamp
What you need to know about clamps
Used in masonry, carpentry, and generally DIY projects, clamps allow you to keep any type of work still and fixed to the spot.
Whether you are clamping to your workbench or holding multiple pieces of an assembly together, whether you’re glueing, drilling, cutting, or welding, a clamp helps to keep your work from moving out of place.
Clamps differ from one another in two key ways: their clamping capacity (a combination of length, from a few centimetres to several meters; depth, up to about 20 cm; and power, as high as 1200 kg of clamping force) and operation which can be carried out in several ways.
- Screwing – as is the case with C-clamps, tightening or loosening a screw adjusts the opening of the clamp.
- Striking - think of mason clamps, which are hammered down into the substrate beneath the masonry to secure it.
- Squeezing – most hand clamps can be done ‘one-handed’ either using a spring or a ratchet system to apply pressure.
A few words about the main clamps
Whatever your project, you will find a suitable clamp.
- The spring clamp: these will meet about 40% of the needs by themselves. It is the most robust and powerful variety. The spring, which provides the force to the clamp, is usually completely protected from blows or dirt. Look for models with sturdy metal handles, as this will extend the lifespan of your clamp. Longer handles are also an advantage as they allow for easier use or for high clamping force. These clamps are perfect for glueing or fixing an assembly of parts.
- The screw clamp: a little less elaborate and less powerful. Tightening or loosening a screw adjusts the opening or the force of the clamp. The clamping force of these models is only actually limited by the strength of your arm.
- The masonryclamp: as indispensable to the mason as the wheelbarrow. Tightening is carried out by striking the slide which moves along a steel rail.
- The "one hand" or hand-pump clamp: as the name indicates, it can be operated with one hand. The hand pump operates a ratcheting system which tightens one side of the clamp. These models are limited in their power (roughly a hundred kg).
A final recommendation
Consider buying your clamps in pairs to help balance the clamping forces.
The pressure that many clamps exert may easily mark wood or other soft materials. Be sure to take measures to protect them and avoid overtightening.
Do not hesitate to buy an extra clamp now and then. You will surely find that you always have a use for another clamp here or there.
For DIY enthusiasts interested in knowing how to choose the accessories related to clamps, follow the advice of our editors and discover their Guides:
- How to choose an edge bander
- How to choose a mortiser
- How to choose a drill
- How to choose a circular saw
- How to choose a hacksaw
- How to choose a compressor
And to work safely:
Guide written by:
Dennis, self-taught DIYer, Bristol, 18 guides
I started doing DIY 10 years or so ago, when I bought a house that needed to be renovated. After having installed loft isolation, and having refurbished the bathroom, the toilets, the kitchen, the bedrooms… I built an extension, installed a new fence with a gate and kitted out the house with a solar panel to make hot water. I have poured tens of tonnes of concrete into slabs or into the foundations and renovated the roof… I can say that building materials and tools are no stranger to me! If I had a pound for every hour spent looking up information in forums and DIY magazines to find solutions to my problems, I'd be a millionaire! So passing on my knowledge on tools and home equipment is natural, as it is just giving back what I borrowed.