What size screw does NEMA 23 stepper motor, 3A variant use?

M3 × 4–6 mm for front mounting holes tapped M3, 3.18mm deep.

How long are the screws in NEMA 23 stepper motor, 3A variant?

The records range from 4 to 6 mm depending on the position, so match each screw to its own hole.

What is the thread pitch of an M3 screw?

0.5 mm (coarse), which is the standard pitch for M3 machine screws; a 0.35 mm fine pitch exists but is uncommon. The tap drill is 2.5 mm and the normal clearance hole is 3.4 mm.

What screwdriver do I need for NEMA 23 stepper motor, 3A variant?

The sources do not name the drive. For M3, Phillips heads normally take PH1 and Torx heads T10; socket heads take a 2.5 mm hex key.

Can I use an imperial screw instead of M3?

No. Imperial look-alike: #5-40 (3.18 mm) or #4-40 — neither interchanges with M3. Use a true M3 screw so it does not cross-thread or strip the hole.

Where can I buy replacement screws for NEMA 23 stepper motor, 3A variant?

TechSpareWarehouse (our own store) lists M3 x 4mm, M3 x 5mm and M3 x 6mm, which match lengths in the records above.

NEMA 23 stepper motor, 3A variant screw size

M3 · 4 to 6 mm long

NEMA 23 stepper motor, 3A variant takes M3 metric screws in lengths from 4 to 6 mm.

The record covers front mounting holes tapped M3, 3.18mm deep.

This entry is marked confirmed and comes from novanta.com.

An M3 screw is 3 mm in diameter with a 0.5 mm pitch, tapped with a 2.5 mm drill; imperial look-alike: #5-40 (3.18 mm) or #4-40 — neither interchanges with M3.

NEMA 23 stepper motor, 3A variant screw specifications

One row per fitment record. Head, drive are shown only where the source states them; pitch is the ISO coarse pitch for the thread.

Thread	Length	Pitch	Head	Drive	Where it goes	Status
M3	4–6 mm	0.5 mm	not stated	not stated	Front mounting holes tapped M3, 3.18mm deep	Confirmed

Fitment records and sources

M34-6mmconfirmed

Front mounting holes tapped M3, 3.18mm deep

pitch 0.5 mm · tap 2.5 mm · clearance 3.4 mm · PH1 / Torx T10

Source

How to check the screw before you buy

Into printed plastic, the screw either self-taps or needs a heat-set insert; machine screws straight into plastic strip easily.
Diameter: across the threads an M3 screw measures about 3 mm with calipers (usually a hair under). If yours measures noticeably more or less, it is a different thread.
Pitch: 0.5 mm from one thread crest to the next (20 crests per centimetre). A thread pitch gauge or the pitch-gauge tool settles it in seconds.
Length: measure from under the head to the tip for pan, button, wafer and cap heads; countersunk (flat) heads are measured overall.
The records span 4–6 mm, which means different positions take different lengths — match each hole to its own screw.
Driver: the source does not name the drive. Standard M3 heads take PH1 for Phillips and T10 for Torx, and a 2.5 mm hex key for socket heads; a bit that fits loosely will cam out and strip the head.
Tightening: no device-specific torque is published in these records. The site's general figure for M3 is about 80-130 N·cm into metal threads and 35-60 N·cm into plastic bosses; snug it up and stop.

Common mix-ups with M3

M3 is the most common FPV screw, but length must match arm and stack thickness — too long can short motor windings or crack frame plates.
NEMA 23 steppers in the 6A frame use imperial #4-40 / #2-56 threads, not M3 - check the datasheet before ordering metric.

Pitch gauge · Screw size finder · Torque guide

Buy these screws at TechSpare Warehouse

In stock and shipped from South Carolina. Our black screws are Phillips wafer head (low profile); match the head style and length to the original before you order.

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The same screw also fits

Devices whose records share a thread with NEMA 23 stepper motor, 3A variant, closest length match first.

Arduino Uno / Mega mounting holes also M3 × 6 mm
ESP32 DevKit boards also M3 × 6 mm
Ender 3 V2 hotend and hotend cover also M3 × 6 mm
Arduino Mega 2560 mounting holes also M3 × 6 mm
OpenBeam / MakerBeam 15x15 mm extrusion also M3 × 6 mm
Voron 2.4 electronics bay also M3 × 6 mm
Linear rail carriage block also M3 × 6 mm
Carbide3D Shapeoko 5 Pro CNC router also M3 × 6 mm

Questions about NEMA 23 stepper motor, 3A variant screws

What size screw does NEMA 23 stepper motor, 3A variant use?: M3 × 4–6 mm for front mounting holes tapped M3, 3.18mm deep.
How long are the screws in NEMA 23 stepper motor, 3A variant?: The records range from 4 to 6 mm depending on the position, so match each screw to its own hole.
What is the thread pitch of an M3 screw?: 0.5 mm (coarse), which is the standard pitch for M3 machine screws; a 0.35 mm fine pitch exists but is uncommon. The tap drill is 2.5 mm and the normal clearance hole is 3.4 mm.
What screwdriver do I need for NEMA 23 stepper motor, 3A variant?: The sources do not name the drive. For M3, Phillips heads normally take PH1 and Torx heads T10; socket heads take a 2.5 mm hex key.
Can I use an imperial screw instead of M3?: No. Imperial look-alike: #5-40 (3.18 mm) or #4-40 — neither interchanges with M3. Use a true M3 screw so it does not cross-thread or strip the hole.
Where can I buy replacement screws for NEMA 23 stepper motor, 3A variant?: TechSpareWarehouse (our own store) lists M3 x 4mm, M3 x 5mm and M3 x 6mm, which match lengths in the records above.

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