Beginner’s Guide to Clamps

Get a grip without spending a bundle.
Large set of clamps on workbench.

Woodworkers need clamps for an endless variety of tasks: securing project parts to the bench as they work on them, serving as a third hand, coaxing reluctant parts together, holding assemblies in place during a dry-fit and while glue dries…well, again, the list is endless.

That’s why you find such a large variety of clamp styles and sizes available. Don’t fret; you don’t need them all (yet). Start with our recommendations for building up an initial clamp collection. You’ll discover which ones you use most often, and which types you wish you had, so you can expand your selections accordingly.

Squeeze the big jobs

These clamps have feet or flat bottoms so they stand in place on a bench as you place project parts on them, such as when gluing up a panel. 

Pipe clamps ($22 including 36" pipe)

With pipe clamps, you really only purchase the fixtures that fit onto 12 " or 34 " pipes that you buy separately. Even so, the combined cost remains the cheapest option for clamps with a long reach. Buying your own pipe means you can make clamps any length you like. (Have the ends threaded, if they aren’t already.) The fixed jaw of the clamp fixture threads on one end, and the movable jaw slides along the pipe. With couplers, you can join pipes to make even longer clamps [Photo A]. 

Pipe clamps with couplers.
A pipe coupler joins two shorter pipe clamps for wide glue-ups, so you need not buy and store long pipes.

The shallow jaws work well for panel glue-ups and carcase assembly, but limit the reach on thick workpieces or into the interior of a wide assembly. The beefy Acme threads of the fixed jaw apply lots of pressure, but even 34 " pipe can flex after too many twists of the handle. On the downside, long clamps weigh a lot, and wet glue can react with the pipe and wood, leaving black marks on your assembly.

Our recommendation: Start with four sets of clamp fixtures, four 2' pipes, two 4' pipes, and three couplers.

Aluminum bar clamps ($30 for 36") 

With a jaw depth about the same as that of pipe clamps, the biggest advantages of aluminum bar clamps are their light weight­—about half of comparable pipe clamps­—and that glue contact won’t discolor the wood. They provide sufficient pressure for most panel glue-ups and carcase assemblies [Photo B], but will flex under heavy pressure.

Extra long clamps.
A pawl in an aluminum bar clamp’s movable jaw (inset) holds the jaw in place as you tighten the stationary jaw.

Our recommendation: Consider buying a few in longer lengths if you find similar-length pipe clamps cumbersome.

Parallel-jaw clamps ($45 for 36")

Clamps over lapping one another.
Long jaws reach far enough to apply pressure even with one set of clamps resting on top of the others.

Deep jaws reach farther, and even provide enough capacity for crossing clamps perpendicular to each other [Photo C]. The jaws stay parallel under heavy pressure, and the beefy bars resist bowing, keeping panels flat and pressure even. If you need to move a clamped assembly out of the way, simply stand the clamps on end [Photo D]. On some models, reversing one jaw creates a spreader for pushing pieces apart [Photo E]. As with pipe clamps, the heavy-duty performance reflect in their weight (and price).

Four clamps holding sides on flat board.
Clear your benchtop for further work without sacrificing floor space by standing a glue-up on end.

Clamp that has measurements on it.
Reversing the movable jaw of a parallel-jaw clamp creates a spreader, useful for disassembly.

Our recommendation: Step up to these after you determine if they’ll be useful to your style of work.

The utility players

Woodworking involves more than gluing up panels and cabinets. For the everyday tasks that require temporarily securing something to something else, these clamps come through in the clutch.

F-clamps ($15–$25 for 6–36")

Two clamps side by side board.
Short F-clamps prove ideal for securing a workpiece to your bench, such as when laminating pieces as shown here, or to hold it for sanding or other work.

These workhorses prove indispensable for securing items to your bench [Photo F], clamping drawer and box glue-ups [Photo G], and countless other jobs. The typical 4" jaw depth works for most applications, but available deeper jaws prove useful, too. The twisting action of the handle and the swivel head can shift parts out of position as you tighten the clamp, so when possible, place the movable jaw against the stationary part of an assembly. 

Clamping box.
Hold together glue-ups too small for bar clamps with a few F-clamps.

Two clamps side by side board.
Short F-clamps prove ideal for securing a workpiece to your bench, such as when laminating pieces as shown here, or to hold it for sanding or other work.

Our recommendation: Start with four each in 6" and 18" lengths. You’ll soon be adding more in various sizes, and the moderate price makes it easy to do so. 

One-hand ($18–$25 for 6–18")

Clamping at an awkward angle.
One-hand clamps free your other hand to align parts as you clamp. If the job requires more pressure, add an F-clamp or pipe clamp after getting parts aligned.

When you have only one hand free, use it on the squeeze trigger that advances the jaw of a one-hand clamp [Photo H]. Your grip strength limits pressure (our tests show about 180 psi on average), but with lighter-weight bars than F-clamps, you won’t use these for your most pressing jobs (sorry). Some sport a reversible jaw to create a spreader; others link together to make two clamps function as a longer one [Photo I].

Two clamps linked together.
The fixed jaws of these clamps interlock, combining two clamps into one. Positioning the linked jaws below the bar provides clearance above.

Our recommendation: Buy a couple of 6" and a couple of 12".

For small and odd jobs

Kind of like the last kid called for sides in PE class, these clamps don’t take center stage, but often surprise you with their usefulness.

Spring clamps ($1–$8)


These apply a fixed amount of light pressure concentrated at the pads at the tips of their jaws. A squeeze opens them for positioning. Spring strength varies among types, sizes, and manufacturers, so give them a test squeeze to evaluate clamping pressure before buying. Use one to secure a stopblock to a fence [Photo J], hold a protective paper covering to your bench, or keep a ruler in position while you make marks along it.
Clamping two pieces of boards together.
A spring clamp temporarily holds a stopblock in place on this simple jig, and allows for quick and easy adjustments to its position.

Our recommendation: No need to overdo these; two each in 2", 4", and 6" will take care of most jobs.

Handscrews ($8–$25)

A clamp on a small angle piece of wood. Holding it against a router.
To machine small or odd-shaped workpieces, grip them in a handscrew. The flat jaw sides ride smoothly on a tabletop, and the wood jaws won’t damage cutters.


The deep reach and the ability to cant the jaws out of parallel make handscrews a valuable part of a clamp collection. Because the dual screws turn independently, you can twist just one, using the other as a fulcrum to multiply pressure at the ends of the clamp. And you can grip items in either end [Photo K]. The wood jaws are less likely to mar workpieces, and you can easily modify them to hold non-square items [Photo L]. 

Clamps holding a small dowel in place while drilling a hold through it.
Secure a handscrew to a flat surface, lying down or standing on end, to create a vise. Notch or shape the wood jaws to hold cylinders or other items without parallel faces.

Our recommendation: Get one each in 6", 8", and 12" sizes.

The specialists

Wait to buy these clamps until you have a specific need for them.

Band (or strap) clamp ($20–$35 for 6–23')

Wrap its webbed strap around a glue-up to hold corners together, such as when assembling a box or drawer. Some have blocks with pivoting jaws that protect delicate mitered corners and can accommodate corners other than 90° [Photo M]. The blocks also lift the strap off the workpiece so the strap doesn’t get glued in place or fouled by squeeze-out. Tighten a screw or a ratcheting mechanism to apply pressure.

Clamping an octagone together.
A band clamp conforms to non-square shapes, applying even pressure all around. Pivoting jaws concentrate clamping pressure near each joint.

Corner clamps ($15)

These often serve as a much-needed third hand, aligning perpendicular pieces as you twist the handle to apply clamping pressure. If you see frame-making in your future, a set of four makes life much easier [Photo N].

Using corner clamps
Use a corner clamp to hold mitered pieces in position while the glue dries. These clamps hold the corner of a drawer or carcase as well.

C-clamps ($5–$20)

For the money, nothing beats C-clamps for applying pressure [Photo O]. The crossbar in the screw handle, the hefty threads, and the beefy iron body make these clamps overkill for most jobs. However, the long threaded rod provides a large capacity (after much spinning of the screw).

Clamps a round wheel.
C-clamps provide plenty of pressure for keeping a bandsaw tire in place while stretching it onto the wheel.

Dealing with pressure

Sometimes, such as when bending thin strips around a form to make a curved part, you need a lot of clamping force; but most times you don’t. For example, to glue up a panel from several boards with properly jointed edges that come together with no gaps, you need about 100­­­–150 pounds per square inch (psi) for soft woods, and 175–250 psi for hardwoods. Almost any bar-type clamp can easily apply that much pressure—over one square inch. 

But the force generated by a clamp spreads over the surface area of the joint. A panel glue-up of 1"-thick boards 25" long has a surface area of 25 square inches. To achieve 150 psi over 25 square inches, you need 3,750 pounds of clamping force. If you apply 420 psi per clamp, nine clamps achieve that pressure over the entire joint. With a bit more pressure per clamp, about 470 psi, you can use only eight clamps. 

So how can you know what 420 psi or more feels like? To give an idea, we clamped a hydraulic pressure gauge against scraps of four different wood species to see how much pressure it took to dent the edge, below

Different wood types showing clamps marks on them.

Hydraulic pressure gauge.
In this unscientific test, 380 psi created a significant dent in a pine board. 420 psi made a shallower dent in poplar. 1,000 psi made a barely visible dent in hard maple. And 1,200 psi had no visible effect on white oak, but it did twist the C-clamp.

Because those forces can dent soft woods, either use a clamping caul of harder wood between the clamps and the workpiece, or plan on trimming the panel edges to remove any dents. Or, rather than twist clamps harder, add more clamps.   

Large set of clamps on workbench.
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