Table saw blade arbor size: bores, speed ratings and dado limits

01What is a table saw arbor?

A table saw's arbor is the threaded spindle that carries the blade, or a dado stack, between the inner flange and the arbor nut. The blade's centre hole, its bore, must match the arbor's diameter, and the saw's manual also sets limits on blade diameter, speed rating and, for dado work, stack width. A blade that slides onto the arbor has passed only the first of those checks.

On a table saw the blade sits below the table and rises through a slot in the throat plate, so blade diameter also decides whether the guard, riving knife and insert work as designed. Manuals therefore state the permitted diameter precisely: Makita's 2705X1 accepts blades from 250–255 mm, while DeWalt's DWE7491 manual gives one blade diameter only. A lower limit exists for a reason: in the UK Health and Safety Executive's 2022 guidance on circular saw benches, a blade much smaller than the saw's maximum runs at too low a rim speed, cuts poorly and raises kickback risk, and HSE asks for the smallest safe diameter to be marked on the machine. HSE puts that floor at about 60% of the largest blade diameter the saw accepts.

Arbor fit rules for handheld saws differ in detail, with diamond knockouts and track-saw bores, and are covered separately under circular saw arbor sizes.

02What arbor size do table saw blades use?

In the US, 10 in table saw blades use a 5/8 in arbor. DeWalt's DWE7491 manual, Makita's 2705X1 manual, Diablo's D1040X specifications and Freud's LU84R011 specifications all give that bore. Compact jobsite saws that take 8-1/4 in blades, such as the Milwaukee 2736-20, use the same 5/8 in arbor, so the two most common table saw blade sizes share one hole.

Blades of the 12 in size are different: Diablo, Freud and DeWalt list a 1 in bore for them. On the machine side, the one maker source on file is Grizzly: its manual for the G0605X and G0606X cabinet saws of that size gives a 1 in bore, and a manual update says later units have a one-piece arbor that no longer accepts blades with the smaller 5/8 in hole. Grizzly's own G0605X product page disagrees, listing both 5/8 in and 1 in as arbor sizes, which suggests older and newer units differ. No Powermatic, SawStop or Delta arbor specification for this size could be read, so owners of a large cabinet saw should read the arbor size from their own manual, and from the saw itself if it may be an older unit.

The table below collects the bore, speed and blade rules published for specific saws and blades.

03How do European table saw bores compare with US arbors?

European table saws use metric blades with a 30 mm bore, larger than the US 5/8 in arbor, so the two are not interchangeable without a maker-approved ring. Bosch's GTS 254 Professional and Makita's UK 2704N and MLT100N all list that metric bore, and the table above gives their blade sizes.

Diameters need the same care. The Makita UK saws take blades of their own metric size, and Makita's US 2705X1 accepts only a narrow range of 250–255 mm; DeWalt's DWE7491 accepts a single diameter. Combined with the bore difference, the practical rule is to buy blades for the market the saw was sold in, or to confirm in the manual that a ring for the other bore is supplied.

04Can you use a reducer ring or spacer on a table saw?

Not an improvised one: DeWalt's DWE7491 manual says not to use spacers to make a blade fit the spindle, and US workplace rules for woodworking machinery require tools mounted on an arbor to be machined to fit it. A blade with a bore larger than the arbor would rely on a spacer to centre it, which is the arrangement DeWalt forbids.

Where a maker designs a ring or adapter into the saw, the rule is to use exactly that part. Makita says that where a saw uses a bore ring, the ring must match the blade's hole, because the wrong ring can let the blade move and vibrate severely. DeWalt's DWS780 miter saw is one published example of a factory adapter: its spindle takes 5/8 in holes, and DeWalt supplies an adapter for 1 in bores. No table saw manual in the fact base lists a similar adapter, and no manufacturer source approves third-party reducer bushings.

05Is a blade's speed rating high enough for your table saw?

It is when the maximum speed marked on the blade equals or exceeds the speed the saw's manual requires. DeWalt is specific: blades used on the DWE7491 must be rated for 5000 rpm or more. Makita's 2705X1 runs at a lower no-load speed, and the Milwaukee 2736-20 runs at 6300 rpm, which is higher than either.

Most full-size blades clear these figures with room to spare, but the check matters for compact saws. Diablo marks its Diablo D1080X 10 in 80-tooth Ultra Finish saw blade for wood for 6000 rpm, comfortably above the DeWalt requirement. A blade borrowed from another machine, or a smaller blade fitted to a fast compact saw, needs its marking read against the saw every time. Freud does not list a maximum speed for some of its blades in the specifications on file, so for those the marking on the blade itself is the only reliable figure.

06Does every blade with the right bore work with the riving knife?

No. The riving knife must match the blade: the blade body must be thinner than the knife and the kerf wider than it, so the cut opens around the knife without binding. DeWalt's DWE7491 manual sets a range of body and kerf thickness for its knife, and a full-kerf blade with a thick plate can fall outside it even though its bore fits the arbor perfectly.

Kerf and plate figures are published for most blades. Full-kerf blades cut a slot of about 1/8 in; thin-kerf blades are narrower, with published examples of .087-.098 in. For example, the full-kerf Freud LU80R010 10 in 80-tooth Ultimate Plywood & Melamine blade (full kerf) lists a 0.126 in kerf and a 0.087 in plate, while the Diablo D1080X 10 in 80-tooth Ultra Finish saw blade for wood lists a 0.098 in kerf and a 0.071 in plate. Compare both numbers against your own saw's riving knife specification before buying.

A blade that forces the knife off the saw also gives up the protection it was designed for. The US Consumer Product Safety Commission (CPSC) compared injury rates per 10,000 saws in use in 2017 and found that saws with a traditional blade guard had 7.19 times the blade-contact injury rate of saws with a modular guard and riving knife system. That 2017 comparison is still CPSC's most recent of its kind. Those rates describe the guard design a saw was sold with, not individual blades, but they are the clearest published reason to choose a blade the knife accepts.

Larger saws set their own window. Grizzly's manual for its G0605X and G0606X cabinet saws limits blades to kerf 0.114–0.122 in; body 0.074–0.082 in so that the riving knife fits. That kerf range starts well above the thinnest kerf DeWalt allows on the DWE7491, so a thin-kerf blade that suits DeWalt's knife falls outside Grizzly's range and risks the binding on a standard riving knife that thin-kerf warnings describe. Tooth count, grind and kerf as cutting choices are covered in the guide on tooth count, grind and kerf.

07Which dado stacks fit a jobsite table saw?

A dado stack fits only if its total width and diameter stay inside the saw's own limits, and both of the jobsite saws with published limits cap width at 13/16 in. The arbor's usable length is what restricts width. The two saws differ on diameter: DeWalt's DWE7491 allows a larger dado diameter than Makita's 2705X1, as the table below shows.

A common belief is that any dado set with a 5/8 in bore runs at full width on any table saw of the common size. It does not. Freud sells stacked dado sets in 6 or 8 in diameters with a 5/8 in arbor, and its larger set can cut wider than either jobsite saw allows, so it must be stacked within the saw's limit. Dado work also needs the saw's dado throat plate or insert, because the standard insert interferes or is unsafe; DeWalt sells its dado plate separately.

European dado rules were not covered by any manufacturer or standards source read for this page, so the guidance here applies to the US saws named.

08Which way does a table saw blade face?

The teeth point down at the front of the table, toward the operator. DeWalt's DWE7491 and Makita's 2705X1 manuals both give this orientation, which is the reverse of how a handheld circular saw blade looks when the saw is held upright.

Disconnect the saw before changing the blade, fit the saw's own inner flange, blade, outer flange and arbor nut in the order the manual shows, and check that the riving knife and guard are refitted before the next cut. Leaving the guard off after a blade change is a common pattern in injury data: in CPSC's 2017 special study of emergency-treated injuries in the US, still the agency's most recent in-depth study of its kind, the blade guard was not in use in 88.9% of table saw blade-contact injuries. Newer counts point at the same hands: AccessoryFit's estimate from CPSC's NEISS emergency department data for 2024 is about 33,000 injuries involving bench or table saws treated in US emergency departments that year, counting all table saw injuries rather than blade contact alone, and 85.5% of them were to the fingers. Year-by-year counts and the injury breakdown are on the table saw injury statistics page. If a correctly mounted blade still scorches the cut, the guide on saw blade burn marks works through the causes.

09When does a table saw blade not fit?

A blade does not fit whenever one of the manual's limits is broken, even if the bore matches. The cases the sources on this page describe are:

• Metric bore on an inch arbor. A 30 mm blade is loose on a 5/8 in spindle without the maker's ring.
• Diameter outside the manual's range. The guard and riving knife are designed around it.
• Speed rating too low. DeWalt sets a minimum for the DWE7491.
• Plate or kerf outside the riving knife's range. The bore fits but the knife does not.
• Dado stack too wide or too large. Jobsite saws cap width at 13/16 in.
• Spacers used to take up a loose bore. DeWalt forbids it.

Fit is also tool-specific: blades for other machines follow other rules. Grinder discs use spindle threads, covered under angle grinder disc sizes; band saws use welded loops sized to each machine, covered under band saw blade sizes; and metal or nail-embedded cuts belong to other saws altogether, such as jigsaw blades for metal or demolition recip blades.

10How do you check blade fit on a table saw not listed here?

Five checks against the saw's manual and the blade's markings confirm fit for any table saw.

1. Disconnect power. Unplug the saw before touching the blade, flanges or insert.
2. Read the manual's blade specification. Note the arbor size, the permitted blade diameter or range, and any minimum speed rating.
3. Compare the blade's markings. Bore, diameter and maximum RPM must all fall within the manual's figures.
4. Check plate and kerf against the riving knife. The blade body must be thinner than the knife and the kerf wider.
5. For dado work, check width, diameter and insert. Keep the stack within the manual's limits and fit the saw's dado insert.

11What else should you compare between table saw blades?

Once a blade passes the fit checks, tooth count, grind and hook angle decide how it cuts. Miter saws share many blade sizes but have their own hook-angle and speed rules, set out in the guide to which blades fit your miter saw. To check a specific saw model, use the accessory finder; every blade type on the site is grouped under saw blades by tool, and the other fit guides sit under what fits which tool.

12Questions readers ask