Shortlist · Clamps, T-track and inserts
CNC clamps, T-track and inserts with the thread stated
Approved CNC hold-down clamps, T-track, T-bolts and threaded inserts whose maker states the thread (M6 or 1/4-20) or the track and groove they fit.
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Short answer
Eight approved workholding parts state the thread or groove they fit. On an M6 table, choose Genmitsu's toe clamp or Mini Vise Clamps, and E-Z LOK 900610-13 inserts for MDF. On a 1/4-20 setup, choose E-Z LOK's 1/4-20 insert kit or POWERTEC's universal T-track and T-bolts. MICROJIG's dovetail and ramp clamps need a routed dovetail groove, not a thread.
How we chose
A part is on this list only if:
- The maker states the thread or track. M6 and 1/4-20 do not interchange. Carbide 3D's Essential Clamps ship with M6 hardware for its Hybrid Table, and Carbide 3D says you can use them with 1/4-inch hardware on your own T-track or inserts,[1] which means swapping the hardware. Genmitsu's toe clamp uses M6 screws and nuts.[2] For reference, Rockler's Universal T-Track is 3/4 in wide by 3/8 in deep;[3] POWERTEC lists the same outside size for its universal track.
- Inserts state the drill and the wood. E-Z LOK lists a 23/64 in drill for its M6 E-Z Hex inserts and 25/64 in for its M6 E-Z Knife.[4] Its 900610-13 is listed for soft woods including MDF.[5] Carbide 3D sells its own M6 and 1/4-20 inserts with a 9 mm pilot hole.[6]
- Clamps that skip threads state their groove. MICROJIG's MATCHFIT clamp fits a 1/2 in x 14-degree dovetail groove routed 3/8 in deep,[7] and its MATCHFIT Ramp Clamp fits any 1/2 in x 14-degree dovetail track.[8]
- The brand sells where we link. MICROJIG names Amazon and Amazon Canada among its online retailers,[9] and POWERTEC names Amazon among its channels.[10]
- It is in our approved catalog with a store listing.
Seven parts met this bar on 2026-10-11 and an eighth on 2026-10-31. We do not add others to fill the list.
M6 low-profile toe clamp
Genmitsu Upgrade CNC Router Vise Clamp, low-profile aluminum toe clamp (101‑63‑VC), 2 or 4 pieces
Pick it if: M6 spoilboards and M6 T-track
- Why it's here
- Genmitsu's aluminum toe clamp uses M6 screws and nuts, measures 106 x 22 x 15 mm, and is listed for T-track tables, hybrid tables and MDF or aluminum spoilboards with M6 holes on Genmitsu 4030 and larger machines.
- Watch out
- M6 only; it does not take 1/4-20 hardware. Genmitsu gives no holding force. Sold in 2- and 4-clamp packs. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or Genmitsu.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
Smaller M6 clamp for small machines
Genmitsu Mini Vise Clamps for CNC routers (101‑63‑MVC), 2 or 4 pieces
Pick it if: Small Genmitsu and other desktop machines with M6 tables
- Why it's here
- Genmitsu sells its Mini Vise Clamps for work boards with M6 holes, T-track, hybrid and MDF spoilboards, in a smaller body than its toe clamp.
- Watch out
- M6 only, and Genmitsu gives no holding force. Smaller stock and lighter cuts suit it better than large panels. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or Genmitsu.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
M6 inserts for an MDF spoilboard
E-Z LOK E-Z Hex threaded insert for soft wood, flanged, M6‑1.0 x 13 mm (900610‑13), 50 pack
Pick it if: Building or repairing an M6 MDF spoilboard
- Why it's here
- E-Z LOK's 900610-13 is a flanged, hex-drive, zinc-alloy insert with an M6-1.0 thread, listed for soft woods including MDF and plywood; its drill chart gives a 23/64 in drill.
- Watch out
- For soft wood; E-Z LOK lists a different insert (the brass E-Z Knife 400-M6) for hard woods. No pull-out rating was found. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or E-Z LOK.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
1/4-20 insert kit for soft wood
E-Z LOK E-Z Hex 1/4‑20 x 10 mm flanged insert installation kit for soft wood (EZ‑901420‑10)
Pick it if: Adding 1/4-20 points to an MDF board or fixture
- Why it's here
- E-Z LOK's kit holds ten flanged 1/4-20 E-Z Hex inserts with a drill and an installation tool, for soft woods such as MDF.
- Watch out
- Ten inserts is a starter quantity. E-Z LOK's drill chart lists 23/64 in for these inserts while the kit page names a Letter U drill; use the drill supplied. 10 mm inserts need bolts sized to that depth. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or E-Z LOK.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
Universal T-track for 1/4-20 and 5/16-18 hardware
POWERTEC 71373 48 in double-cut profile universal T-track, 4 pack
Pick it if: Building a T-track spoilboard for 1/4-20 clamps
- Why it's here
- POWERTEC lists the 71373 as four 48 in extruded aluminum universal tracks, 3/4 x 3/8 in, that accept 1/4 in hex bolts and 1/4 and 5/16 in T-bolts. POWERTEC names Amazon as one of its sales channels.
- Watch out
- Mounting screws are not included, and the track must be let into or fixed onto your board. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or POWERTEC.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
1/4-20 T-bolts for universal track
POWERTEC 1/4‑20 T-track bolts, 3‑1/2 in long, 20 pack (QTB1006)
Pick it if: Universal T-track tables with 1/4-20 clamps
- Why it's here
- POWERTEC's 1/4-20 T-bolts come in 20-packs; QTB1006 is the 3-1/2 in length, made for universal T-track or larger.
- Watch out
- POWERTEC says they do not fit 1/4 in or mini T-track. Check that 3-1/2 in suits your clamp and stock height. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or POWERTEC.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
Dovetail-groove clamps, no thread needed
MICROJIG MATCHFIT Dovetail Clamps, 2 pack (DVC‑538K2)
Pick it if: Fixture plates and spoilboards with routed dovetail grooves
- Why it's here
- MICROJIG's MATCHFIT dovetail clamp fits a 1/2 in x 14-degree dovetail groove routed 3/8 in deep, so it works in grooves cut into a spoilboard or fixture rather than a threaded hole. MICROJIG names Amazon and Amazon Canada among its online retailers.
- Watch out
- You must rout the matching groove first. We publish no holding-force figure for it. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or MICROJIG.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
Low-profile dovetail-track clamps
MICROJIG MATCHFIT Ramp Clamp, 2 pack (CN‑P3K2)
Pick it if: Holding stock edge-on in dovetail tracks routed into a spoilboard or fixture
- Why it's here
- MICROJIG's MATCHFIT Ramp Clamp has a low-profile, rotating head that presses forward and down, fits any 1/2 in x 14-degree dovetail track, and MICROJIG lists CNC among its uses.
- Watch out
- You must rout the dovetail track first, in 3/4 in or thicker stock per MICROJIG. MICROJIG states no clamping force. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or MICROJIG.
- Mount (body) diameter
- Not stated
- Collet system (ER11, ER16, ER20, router collet)
- Not stated
- Shank sizes held
- Not stated
- Spindle power and supply voltage (maker claim)
- Not stated
Fit at a glance
| Part | Thread or groove | Goes into |
|---|---|---|
| Genmitsu toe clamp (101-63-VC) | M6 | M6 holes, M6 T-track, hybrid tables |
| Genmitsu Mini Vise Clamps (101-63-MVC) | M6 | M6 holes, T-track, MDF spoilboards |
| E-Z LOK 900610-13 | M6-1.0 internal | Soft wood, 23/64 in drill |
| E-Z LOK EZ-901420-10 | 1/4-20 internal | Soft wood, drill supplied |
| POWERTEC 71373 track | 1/4 in and 5/16 in T-bolts, 1/4 in hex bolts | Routed into a board |
| POWERTEC QTB1006 | 1/4-20 T-bolt, 3-1/2 in | Universal T-track |
| MICROJIG DVC-538K2 | 1/2 in, 14-degree dovetail | Routed groove, 3/8 in deep |
| MICROJIG CN-P3K2 ramp clamp | 1/2 in, 14-degree dovetail | Routed track, 3/4 in or thicker stock |
Bolt length matters with any of these. Carbide 3D's Crush-It hardware kit spans M6 bolts from 16 to 40 mm,[11] a reminder that one length rarely suits every clamp and stock height.
See M6 vs 1/4-20 spoilboard threads and the workholding hub.
Questions
Can I use 1/4-20 clamps on an M6 table?
Not with 1/4-20 bolts in M6 holes: they are different threads. Carbide 3D lets you use 1/4-inch hardware with its Essential Clamps on your own T-track or inserts, which means changing the hardware, not mixing threads.[1]
Which drill do I need for M6 inserts?
The one the insert's maker gives for that part. E-Z LOK lists 23/64 in for its M6 E-Z Hex inserts and 25/64 in for its M6 E-Z Knife; Carbide 3D recommends a 9 mm pilot hole for its own inserts.[4][6]
Are Carbide 3D clamps on this list?
Not yet; none is in our approved catalog. Carbide 3D's Essential Clamps ship with M6 screws for its Hybrid Table.[1]