Guide · Miter gauges, T-track and stops
T-track bolts, knobs and stops: thread and head sizes
T-track hardware fits by bolt head size and thread. The sizes Bow, Milescraft, Bosch and Kreg publish, what 1/4-20 and M8 x 1.25 mean, and why stops fit named fences.
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Picks that fit
- Milescraft 4023 TrackMaster universal T-track clamping kitCheck price on Amazon
- POWERTEC 71373 48 in double-cut profile universal T-track, 4 packCheck price on Amazon
Short answer
T-track hardware fits by two things: the bolt head, which has to slide in your track's channel, and the thread, which has to match your knob or accessory. Compare the head dimensions a maker publishes with your track, and match the thread designation exactly.
Picks that fitAll picks and how to choose
- Milescraft 4023 TrackMaster universal T-track clamping kitCheck price on Amazon
- POWERTEC 71373 48 in double-cut profile universal T-track, 4 packCheck price on Amazon
How T-track hardware fits
A T-track is an aluminum channel with a wider slot below a narrower opening. A T-bolt slides in with its head trapped below the lip and its threaded shank sticking up. A knob or nut on the shank clamps the accessory down.
Two numbers decide fit:
- Head size: thickness, width and length must pass through the channel and stay trapped under the lip.
- Thread: the knob, nut or accessory must have the same thread.
"Fits 3/4 in track" is a maker's wording. The head dimensions are what you can actually compare.
Hardware with published sizes
| Hardware | Thread | Head or size the maker publishes | Maker's own fit wording |
|---|---|---|---|
| Bow FeatherPRO (FP1) T-bolts, two | 5/16-18, 1-1/2 in long | 0.090 x 0.45 x 0.725 in | "1/4 to 3/4 in T-tracks" |
| Bow FeatherDUO (FP3) T-bolts | 5/16-18 | 0.090 x 0.45 x 0.725 in | "1/4 to 3/4 in T-track" |
| Milescraft TrackMaster 4023 | One 1/4-20 and three M8 x 1.25 | Four head sizes | Bolt list only (see below) |
| Bosch RA1181 fence featherboard | 1/4-20 x 1-1/2 in carriage bolts | Not given | The fence's top T-slot |
| Kreg True-FLEX | T-track bolt, washer and knob | Not given | T-tracks and T-slots |
Bow
For T-track mounting, Bow's FeatherPRO uses two 1-1/2 in T-bolts with 5/16-18 thread. Bow says they fit 1/4 in to 3/4 in T-tracks, and gives the heads as 0.090 in thick x 0.45 in wide x 0.725 in long.[1] The FeatherDUO uses 5/16-18 T-bolts with the same head size.[2] Bow's track range is its own wording; compare the head size with your channel.
Milescraft
Milescraft's TrackMaster Universal T-Track Clamping Kit (4023) includes a 1/4-20 T-bolt and three M8 x 1.25 T-bolts for different track sizes, and adapts the Milescraft 3 in BenchClamp for T-track use.[3] Milescraft's sentence about which track widths those suit is ambiguous, so we publish only the bolt list. Router tables are among the uses Milescraft lists.
Bosch
On the RA1181, Bosch's fence featherboard mounts with 1/4-20 x 1-1/2 in carriage bolts slid into the T-slot on top of the fence.[4] That is the RA1181's own fence slot; it does not tell you about other fences.
Kreg
Kreg's True-FLEX featherboard mounts in a T-track or T-slot with a T-track bolt, washer and knob, or in a miter slot with a wedge lock.[5] Kreg lists it for miter slots and T-slots on table saws or router tables.[6] The manual gives no slot dimensions.
Rockler
Rockler sells universal T-track hardware. We could not confirm its bolt fit from Rockler's own page, so we make no claim about which tracks it suits.
Thread designations in plain terms
- 1/4-20: an inch thread, 1/4 in nominal diameter, 20 threads per inch.
- 5/16-18: an inch thread, 5/16 in nominal diameter, 18 threads per inch.
- M8 x 1.25: a metric thread, 8 mm nominal diameter, 1.25 mm between threads.
An inch is exactly 25.4 mm[7], so 1/4 in is 6.35 mm. That is close to M6 but not the same, and the thread pitch differs too. A 1/4-20 knob will not run properly on an M6 bolt, or the reverse. Match the designation, not the approximate size.
Stops fit named fences
A fence stop clamps to a particular fence's profile or slot. JessEm says its Router Fence Stop fits the JessEm TA Fence, Mast-R-Fence III and Mast-R-Fence II, but not the original Mast-R-Fence.[8] JessEm's page does not name a track type. Check any stop against the fence its maker names, not against a track width.
Measuring your track
With calipers, measure the channel's top opening, the width of the wider slot below, and the depth from the lip to the floor. Then compare with a bolt maker's published head size. If a maker gives no head size, ask before you buy.
Track hardware with a stated thread
Picks that fit2 products
Milescraft 4023: a clamp kit with one 1/4-20 and three M8 x 1.25 T-bolts; use the bolt whose head fits your track.
More on choosing
POWERTEC 71373: four 48 in T-tracks that POWERTEC says take 1/4 in hex bolts and 1/4 in and 5/16 in T-bolts, for adding track to a shop-made top or fence; screws not included. On Amazon, check that Ships from / Sold by is Amazon.com or the brand.
Milescraft 4023 TrackMaster universal T-track clamping kit
POWERTEC 71373 48 in double-cut profile universal T-track, 4 pack
Next
Questions
What size bolts fit T-track?
The ones whose head fits your track's channel and whose thread matches your knob. Bow publishes a 5/16-18 T-bolt head of 0.090 x 0.45 x 0.725 in; Milescraft's 4023 kit has one 1/4-20 and three M8 x 1.25 T-bolts. Compare the head size with your own track.[1][3]
Is 1/4-20 the same as M6?
No. 1/4-20 is an inch thread (1/4 in diameter, 20 threads per inch); M6 is a metric thread (6 mm diameter). They are different thread systems and do not interchange.[7]
Will a fence stop fit any fence?
No. JessEm says its Router Fence Stop fits the JessEm TA Fence, Mast-R-Fence III and Mast-R-Fence II, not the original Mast-R-Fence. Check any stop against the fence its maker names.[8]
Do Rockler's universal T-track bolts fit other track?
We could not confirm that from Rockler's own page, so we make no claim. Check Rockler's listing for the track it names.