ER32 ER25 ER40 CNC Machining Parts Precise Spring Collet Chuck For Engraving Machine

Need one collet chuck that fits the cutters already in the rack? The ER32 precise spring collet chuck holds engraving and milling tools on a CNC spindle, and the same design is available as ER25 and ER40. A slotted ER collet closes evenly around the shank, so the cutter stays on the centre line the taper gives it. Listed bore designations run from 3.175 mm (1/8 in) through 10 mm to 12.7 mm (1/2 in). Alloy body, Customized OEM, price by quotation.

A shop running a CNC router or an engraving machine hits the same three things: a holder that is true when new and lets the cutter wander after a season of tool changes, a rack of part numbers where nobody knows which chuck each collet belongs to, and one holder bought per shank diameter until the shelf is full of parts that fit nothing else.

It is a precise spring collet chuck: an alloy body with an internal taper, a nut, and a slotted ER collet the nut squeezes closed around the tool shank. The collet closes along its whole length, so the shank is gripped on its full circumference instead of three jaw faces, and the cutter keeps the centre line the taper gives it. That is why one holder runs a 12.7 mm end mill and a 3.175 mm engraving bit without a second chuck.

ER32 is the standard body, with ER25 and ER40 available on the same order. Listed bore designations run from 3.175 mm (1/8 in) through 10 mm to 12.7 mm (1/2 in), covering the shank sizes most engraving and milling setups use.

Customized OEM covers marking and batch specification. Price is by quotation, because body size and bore change the part number.

What separates this chuck from a plain holder is how the parts work together, not one headline number.

• Spring collet grip — The nut compresses a slotted ER collet so it closes along the full shank length; grip spreads over the whole circumference, not three jaw contact points.
• Three body sizes, one design — ER32, ER25 and ER40 share the same collet-and-nut logic, so one wrench serves three spindles.
• Bores from 3.175 mm to 12.7 mm — The listed designations ER20-3.175, ER32-10 and ER25-12.7 cover 1/8 in, 10 mm and 1/2 in shanks from one body.
• Alloy body — Machined from alloy, the material specified for this part, so the taper resists wear from repeated collet changes.
• Concentric clamping — The internal taper centres the collet on the spindle axis; that keeps an engraving cutter cutting where the drawing says it should.
• One holder, many cutters — Different shank diameters go into the same chuck by swapping the collet only, so the rack shrinks to one holder per spindle.
• Engraving and milling — The stated use is tool holding on CNC engraving machines; the same chuck accepts milling cutters on a router spindle.
• Customized OEM — Marking, bore mix and batch specification can be set to the drawing you send.

Most router shops end up choosing between a cheap holder that has to be replaced every season and a spindle tooling package priced for a production cell. This chuck sits where a job shop actually is.

• One holder family, three spindles. ER32, ER25 and ER40 in the same design means a spare bought for today's machine still fits the next one, so you carry 3 part families instead of a shelf of orphans.
• Fewer collets to stock. The listed bores span 3.175 mm to 12.7 mm, so the common 1/8 in, 10 mm and 1/2 in shanks run from one chuck rather than three.
• The cutter stays where you set it. Concentric grip keeps engraving depth even across a full sheet, which is the difference between one pass and a re-cut.
• A worn collet is a part, not a rebuild. Only the collet carries the wear, so service costs one consumable instead of a whole new holder.
• OEM without a design project. Customized OEM is a service line on this part, so your marking or bore mix goes on the order rather than into a tooling budget.
• No pricing surprises. Quotation on request, quoted against the body size and bore you actually need, so you are not paying for a size you will not use.

Match the chuck to the collet family your spindle already takes. ER32, ER25 and ER40 use different nut threads and collet diameters.

No. Each ER body takes only its own collet family, which is why ER32, ER25 and ER40 come as separate bodies.

The listed designations are ER20-3.175, ER32-10 and ER25-12.7, so the range runs from 3.175 mm (1/8 in) to 12.7 mm (1/2 in).

The part is the precise spring collet chuck, with collet bores quoted alongside it. Tell us the bore you need.

The nut is usually not tight enough. Use the proper ER wrench and keep the full shank length inside the collet.

Yes. Both are shank tools; only the collet bore changes, so one body covers a 3.175 mm bit and a 12.7 mm end mill.

Yes. Customized OEM is offered on this part, set against the drawing you send.

Quotation on request. Body size, bore and quantity decide the price, so send the ER size you need.