How to pick a jigsaw blade: shank, TPI, material and avoiding bent blades

01What decides which jigsaw blade you need?

Four attributes decide it: the shank, which must match the saw's blade clamp; the teeth per inch (TPI), which must suit the material's thickness; the blade material, which must be harder than what it cuts; and the tooth form, which sets how fast and how clean the cut is. Length comes fifth and only matters once the stock gets thick.

The order matters. A blade with the wrong shank cannot be fitted at all, so that check comes first. A blade with the wrong TPI fits but cuts badly: too coarse and it snags thin sheet, too fine and it clogs and overheats in thick timber. A blade of the wrong material fits and may cut for a while, then dulls quickly. Tooth form is a refinement you choose once the first three are right.

Jigsaw blades are the most varied of the saw blade guides on this site because one saw is expected to cut softwood, worktops, sheet steel, acrylic and tile. Most packaging prints all four attributes on the blade itself or on the card: shank style, TPI, material code and the intended material, often as a colour code or a short phrase such as clean for wood or basic for metal.

02Does your jigsaw take T-shank or U-shank blades?

Almost every jigsaw sold today takes T-shank blades, and a T-shank saw takes only T-shank blades. DeWalt's manual for the DCS334, for example, says the saw uses T-shank blades only. U-shank blades are still made but are labelled for U-shank saws only.

The T-shank was created by Bosch and replaced its earlier tang-style blades to become the industry standard. Bosch's own marketing says its T-shank blades fit over 90% of current jigsaw makes and models (Bosch claim); no independent count was found to confirm it. Lenox still sells U versions of several T blades, such as its C450U alongside the C450T.

The names catch out European buyers. Bosch's European catalogue calls the T-shank the single lug shank and the U-shank the universal shank. That makes it easy to believe a universal blade fits every jigsaw, which is wrong: universal here is simply Bosch's name for the U-shank. Likewise, T-shank and U-shank blades are not interchangeable even when the toothed part looks identical. The guide to T-shank and U-shank jigsaw blades shows how to tell them apart and which older proprietary shanks exist.

03Which shank do current jigsaws use?

Every jigsaw in our tool fact base takes T-shank blades, which matches the makers' own statements above. The table lists the blade mount and stroke length each maker publishes, so you can confirm a model before buying blades for it.

04How many teeth per inch should a jigsaw blade have?

Match TPI to the material and its thickness: general wood-cutting blades run 6–10 TPI, and metal-cutting blades run 14–36 TPI, with the finest teeth for the thinnest sheet. Lenox's rule of thumb is to keep 2–3 teeth in the material at all times, so thin material needs more, closer teeth and thick material fewer, larger ones.

The table below sets out the TPI and thickness ranges that Lenox and Bosch list for named blades in each material. Read it by material first, then by thickness: a blade listed for medium metal will clog in thick plate and snag in thin sheet. Bosch's European pages give tooth spacing in millimetres between teeth instead of TPI, so a larger spacing figure on a European card means a coarser blade, the opposite of how TPI reads.

05Is a higher TPI always the better blade?

No: more teeth give a smoother cut but a slower one, and in thick stock a fine blade packs its gullets with sawdust, heats up and wanders. Lenox matches TPI to thickness rather than to finish alone, with most wood work in the coarse-to-medium range.

For a clean edge in wood, tooth form often matters more than tooth count. A taper-ground or reverse-tooth blade in the normal wood range can leave a cleaner face than a much finer blade that is struggling to clear chips. Fine scroll blades earn their place on tight curves in thin stock, where their narrow bodies turn more easily.

06Which blade material suits wood, metal and tile?

High-carbon steel (HCS) suits softwood, fibreboard and soft plastics; high-speed steel (HSS) suits metal; bi-metal (BIM) covers hardwood, abrasive wood products, hard plastics and both ferrous and non-ferrous metal. Carbide-tipped, carbide-grit and diamond-grit blades take over for cement board, tile and stone.

Bi-metal is the most versatile choice because it puts hardened HSS teeth on a flexible HCS body, and Bosch recommends it where a blade might snap at the shank. Bosch's catalogue, the only source for this figure, puts bi-metal blade life at about 2x HSS, about 10x HCS. HCS blades are flexible and suit soft materials. HSS is fully hardened and cuts metal well, but it lacks the flexible body that makes bi-metal the safer choice where a blade may bend.

07What do tooth set, grind and direction change?

Tooth form decides the trade-off between speed and finish: milled, side-set teeth cut fast and rough, wavy-set teeth cut fine and straight in thin metal and plywood, and taper-ground teeth leave the cleanest edge in wood and plastic. Bosch's catalogue groups its blades by these forms.

Two other tooth patterns solve specific problems. A reverse-tooth or down-cut blade cuts on the down stroke, so the top face stays free of splinters; it suits laminate worktops and veneered panels cut from the good side. A progressive-tooth blade changes pitch along its length, so one blade can handle thin and thick material across a range of densities, which makes it a useful general blade for mixed jobs such as timber with hidden nails.

08Which jigsaw blade cuts plastic, plexiglass and polycarbonate?

For plastics, use a blade whose maker lists plastic, run at a low saw speed: HCS blades for soft plastics, bi-metal blades for hard plastics, and a taper-ground tooth form for the cleanest edge. DeWalt's DCS334 manual puts plastics among the materials that need a lower speed, along with tile, laminate, hard metals and cast iron.

Acrylic, sold as Plexiglas, Perspex or PMMA, has its own blade in Bosch's range. Bosch lists the T 102 BF (13 TPI, bi-metal) as its Clean for PMMA blade, made to leave an edge that needs no rework. For polycarbonate sheet, Bosch's accessory catalogue gives a different blade, the T 101 A (HSS) Clean for PC, with ground, taper-ground teeth. Both are Bosch's own recommendations and no second maker in the fact base names an equivalent, so with other brands look for plexiglass, acrylic or polycarbonate on the blade card rather than assuming any fine blade will do. Both Bosch blades are T-shank.

The saw setting matters as much as the blade. DeWalt designs orbital action for soft materials such as wood or plastic, so its manual allows it on plastic, but it also notes that orbital cuts are less smooth; for a visible edge on acrylic or polycarbonate, a straight stroke at the lower speed DeWalt recommends for plastics is the cleaner choice.

09How long should a jigsaw blade be?

A jigsaw blade must be long enough to stay in the cut through the full stroke, and Lenox sizes the minimum length as material thickness + 2 to 2-3/4 in, the extra depending on the cut. Most blades in the Bosch and Lenox ranges are 2-3/4 to 5-1/4 in (70 to 133 mm) long.

Longer is not automatically better. A long, narrow blade flexes more, so for thin sheet and tight curves the shortest blade that clears the stock gives the most control. For thick timber, a longer specialist blade is needed, and Bosch makes some for construction timber. Width also affects curves: narrow scroll blades turn tighter radii, while wide blades track straighter.

10When should orbital action be off?

Orbital action should be off for metal and hardwood. DeWalt's DCS334 manual says those materials should never be cut with orbital action and reserves the orbital settings for soft materials such as wood and plastic, where they cut faster but less smoothly. The belief that orbital action improves every cut is therefore wrong.

Speed follows the same logic. DeWalt's manual advises lower speed for plastics, tile, laminate, hard metals and cast iron, and higher speed for wood and soft metals. Numbering of orbital settings varies between saws, so the table below shows DeWalt's scheme as an example; check your own saw's manual for its scale.

11How do you pick a jigsaw blade, step by step?

These steps turn the attributes above into a blade choice for one job.

1. Check the saw's shank. Look at the blade clamp or the manual. Most current saws are T-shank; buy U-shank only for a saw built for it.
2. Name the material. Softwood, hardwood, laminate, plastic, sheet metal, plate, cement board or tile each point to a different blade material.
3. Measure the thickness. Choose TPI so several teeth stay in the material: coarse for thick timber, fine for thin sheet.
4. Choose the blade material. HCS for softwood and soft plastic, bi-metal for hardwood, hard plastic and mixed work, HSS or bi-metal for metal, carbide or grit for tile and board.
5. Pick the tooth form for the finish. Side-set for fast rough cuts, taper-ground or wavy-set for clean cuts, reverse-tooth for a splinter-free top face.
6. Check the length. Add the Lenox allowance to the thickness and pick a blade at least that long, but no longer than needed.
7. Set the saw. Orbital off for metal and hardwood, lower speed for plastic, tile and hard metals.

12Why do jigsaw blades bend, wander or snap?

The causes makers name are forcing the saw, using orbital action on metal or hardwood, and a brittle blade where the shank takes the load. DeWalt's jigsaw manual says not to force the saw but to let the blade cut at its own speed; pushing harder makes a thin blade deflect sideways, which shows as a bevelled or curved edge.

Orbital action on hard material adds to the problem, because the blade is driven forward into wood or metal it cannot clear quickly. Where blades break at the shank, Bosch recommends switching to flexible bi-metal blades. In thin sheet metal the sheet itself vibrates and tears unless wood is clamped underneath it.

Other likely causes, such as a blade that is too thin for the cut or a dull blade, are widely discussed, but the manufacturer documents in our fact base do not tie them to wandering cuts, so this page does not state them as rules. If a cut still drifts with the right blade at a steady feed, the saw's blade guide roller and clamp are the next things to check in its manual.

14When is a jigsaw the wrong saw for the cut?

A jigsaw is the wrong saw when the cut is long and straight in thick timber, when the stock is deeper than any blade can clear, or when the job is demolition. A band saw handles deep curved cuts with a continuous blade, and the guide to band saw blade length and width covers sizing for those machines. For cutting through nailed framing or pipe in place, a reciprocating saw with demolition recip blades is the faster tool.

To find the blades that fit a specific saw model, the accessory finder filters by tool, and the other how-to guides cover drill bits, router bits and abrasives in the same way.

15Questions readers ask