Buying task · Spindle kits
Spindle kits: body size, collet system, cooling and the maker's supply rules
How to choose a CNC spindle kit: the machines its maker names, 65 or 80 mm body, ER collet system, the supply it states, cooling, and what the kit leaves out.
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Short answer
Choose a spindle kit whose maker names your machine and Z axis, then check its body size against your mount, its collet system against the shanks you run, and the supply it states against what a qualified electrician says your shop has. Read the contents list before you buy: some kits leave out the mount, coolant or a finished drive enclosure.
What a spindle kit is
A spindle kit pairs a spindle motor with a VFD (the drive that powers it and sets its speed) and some of the parts needed to run it, in place of a trim router. What "some" means differs by maker. A finished system goes further: PwnCNC's Spindle System has its VFD installed in a finished enclosure, programmed for the selected motor and tested before shipment.[1]
Whether to switch at all is covered in keep the trim router or move to a spindle.
The decisions, in order
1. The maker names a kit for your Z axis. Carbide 3D says its 65 mm VFD Spindle Kit should fit the Shapeoko 3, Shapeoko 4, Shapeoko Pro and Shapeoko 5 Pro and is not compatible with other CNC machines.[2] It does not recommend the kit on a Shapeoko 3 with the original belt-driven Z axis because of the spindle's weight.[3] Its 80 mm kit guide lists the Shapeoko 5 Pro as the only supported machine.[4]
2. Body size. The body must match your mount: 65 mm or 80 mm for most kits. In PwnCNC's kit, the 65 mm mount pairs with ER11 motors and the 80 mm mount with ER20 motors.[5] See 65 mm vs 80 mm spindles and the mounts hub.
3. Collet system for your shanks. Carbide 3D lists its ER16 65 mm kit as a 110 V, 12 A, 1,200 W rated, air-cooled spindle with an 8,000-24,000 RPM range.[3] Onefinity's 65 mm 1.5 kW Redline kit includes an ER11 nut with 1/4 and 1/8 in collets,[6] while its 80 mm 1.5 kW kit has an ER20 nut with 1/2, 3/8, 1/4 and 1/8 in collets.[7] If you run 1/2 in bits, the collets hub explains why ER20 matters.
4. The supply the kit states. Carbide 3D says its 65 mm kit is 110 V only, does not work on 220 V and does not work on a GFCI outlet.[2] Its 80 mm kit uses a 220 V VFD with an L6-20 plug, while the CW3000 chiller runs on a standard 110 V NEMA 5-15 outlet.[4] PwnCNC lists its 1.5 kW motors at 110 V and 12 A and its 2.2 kW 80 mm ER20 motor at 220 V and 10 A.[8] Onefinity's 80 mm 2.2 kW Redline kit is 220 V single-phase with a NEMA 6-15P plug.[9] Onefinity's Redline pages say the VFD requires a 15 A breaker and warn that GFCI installation may cause frequent false tripping.[6] These are the makers' requirements, not advice to change your wiring. The 110 V vs 220 V guide and UL, ETL, CSA and CE marks go further.
5. Cooling and what you must add. PwnCNC's water-cooled kits include a 110 V pond pump and tubing but no coolant or reservoir, and no finished VFD enclosure.[5] See air-cooled vs water-cooled kits.
6. Kit or finished system. A kit leaves the drive enclosure to you; a finished system arrives built and tested. PwnCNC sells both.[1]
How to choose
No spindle kit is in our approved catalog yet, so we name none. Two approved parts fit steps 2 and 3 for readers who already own an 80 mm ER20 spindle.
Picks that fit2 products
Genmitsu GA-RZC-80: the 80 mm holder Genmitsu lists for the 4040-PRO MAX and 3030-PROVer MAX/Ultra only (PROVerXL machines use a different SKU).
More on choosing
Genmitsu ER20 set: the 14-piece set, 1/16 to 1/2 in, for an ER20 spindle nose and nut only. On Amazon, check that 'Ships from / Sold by' shows Amazon.com or the brand.
80 mm holder for the 4040-PRO MAX and 3030-PROVer MAX/Ultra
Genmitsu 80 mm aluminum spindle holder (GA‑RZC‑80) for the 4040‑PRO MAX and 3030‑PROVer MAX/Ultra
ER20 set up to 1/2 in
Genmitsu ER20 router collet set, 14 pieces (1/16 in to 1/2 in)
Every page on spindle kits
Guides
- Keep the trim router or move to a spindle?
- 65 mm vs 80 mm spindles: collet, supply and what else changes
- Air-cooled vs water-cooled spindle kits: what each package includes
- 110 V vs 220 V spindles, kW labels and what the maker requires
- Carbide 3D 65 mm VFD spindle: ER11 (V1) vs ER16 (V2)
- Spindle upgrade checklist: kit, system and the parts you still need
- UL, ETL, CSA and CE marks on spindle kits and VFDs
Where kits fit
- CNC part finder by machine and Z axis
- 65 mm mounts and 80 mm mounts
- ER11, ER16 and ER20 collet systems
Key terms
Air-cooled spindle, water-cooled spindle, chiller, rated power, supply voltage, NEMA plug and GFCI.
Everything in this topic
Guides
- 65 mm vs 80 mm spindles: collet, supply and what else changesHelps you decide between a 65 mm and an 80 mm spindle by the collets, supply and parts each kit's maker lists.
- Air-cooled vs water-cooled spindle kits: what each package includesHelps you compare spindle kits by what is in the box and what you must add, rather than by claimed cooling benefits.
- Carbide 3D 65 mm VFD spindle: ER11 (V1) vs ER16 (V2)Helps you tell which Carbide 3D 65 mm spindle you own and buy collets and parts for that version only.
- 110 V vs 220 V spindles, kW labels and what the maker requiresHelps you shortlist spindle kits whose stated supply matches the circuit you already have, without adapting plugs or outlets.
- Spindle upgrade checklist: kit, system and the parts you still needHelps you list every part a spindle upgrade needs before ordering, using each kit maker's own parts list.
- Keep the trim router or move to a spindle?Helps you decide whether a spindle kit is worth it for your machine, using the makers' stated collets and supply rules.
Common questions
Can a 65 mm spindle run 1/2 in bits?
Not the 65 mm kits we found. Carbide 3D's current 65 mm kit lists a 3/8 in maximum cutter, and a 1/2 in shank is outside the ER16 ranges Galaxy, Command Tool and Somma publish. For 1/2 in, look at ER20 spindles. More in 65 mm vs 80 mm spindles: collet, supply and what else changes
Do 80 mm spindles need 220 V?
Not always. Onefinity sells an 80 mm 1.5 kW kit at 110 V and an 80 mm 2.2 kW kit at 220 V; Carbide 3D's 80 mm kit uses a 220 V VFD. Quote the kit you are looking at, and let an electrician confirm your circuit. More in 65 mm vs 80 mm spindles: collet, supply and what else changes
What else do I need to buy with an 80 mm spindle?
A mount your machine's maker names for 80 mm, an 80 mm dust boot, a hose that will not clog, and ER20 collets for every shank you run. Carbide 3D warns that 35 mm hoses can clog with its 80 mm spindle. More in 65 mm vs 80 mm spindles: collet, supply and what else changes
Does a 65 mm spindle always use ER11?
No. PwnCNC and Onefinity pair 65 mm with ER11, but Carbide 3D's 65 mm kit has used ER16 since May 2025. More in 65 mm vs 80 mm spindles: collet, supply and what else changes
Does a water-cooled spindle come with a pump?
It depends on the kit. PwnCNC's water kits include a 110 V pond pump and tubing but no coolant or reservoir; Carbide 3D's 80 mm kit includes a CW3000 chiller. More in Air-cooled vs water-cooled spindle kits: what each package includes
What coolant should I use?
That is outside our scope. Follow the spindle maker's manual; Carbide 3D's 80 mm kit, for example, does not include coolant. More in Air-cooled vs water-cooled spindle kits: what each package includes
Is a water-cooled spindle quieter?
Not established. We found no source that measures noise for air-cooled vs water-cooled spindles. More in Air-cooled vs water-cooled spindle kits: what each package includes
Can I run a water-cooled spindle without the pump on?
No. PwnCNC says water-cooled spindles should not be operated without coolant flow. More in Air-cooled vs water-cooled spindle kits: what each package includes
Questions
Do I need 220 V for a spindle?
Not for every kit. Carbide 3D's 65 mm VFD kit is 110 V only, and Onefinity's 1.5 kW Redline kits are 110 V; Onefinity's 2.2 kW Redline and PwnCNC's 2.2 kW kits are 220 V. Follow the kit maker's manual and have a qualified electrician decide on the circuit.[2][6][9][5]
Which spindle kit fits my machine?
One whose maker names your machine and Z axis. Carbide 3D says its 65 mm kit should fit the Shapeoko 3, 4, Pro and 5 Pro and is not compatible with other machines, and its 80 mm kit guide lists the Shapeoko 5 Pro as the only supported machine.[2][4]
What does a spindle kit not include?
It varies, so read the contents list. PwnCNC's water-cooled kits include a pump and tubing but no coolant or reservoir, and no finished VFD enclosure; its Spindle System adds a finished, programmed and tested enclosure.[5][1]
Is a spindle quieter than a router?
That is not established. The only maker statement we found, from Sienci, says its AutoSpin spindle has no noise advantage over the Makita RT0701C at the same RPM.[10]