---
product_id: 245713294
title: "CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor"
brand: "cnctopbaos"
price: "5367287₫"
currency: VND
in_stock: true
reviews_count: 6
url: https://www.desertcart.vn/products/245713294-cnctopbaos-engraving-machine-rotary-4th-axis-cnc-router-rotation-fourth
store_origin: VN
region: Vietnam
---

# 100mm K12 4-jaw self-centering chuck for versatile clamping 12kg.cm holding torque Nema23 stepper motor for powerful control 100:1 gapless harmonic gearbox for ultra-precise rotation CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor

**Brand:** cnctopbaos
**Price:** 5367287₫
**Availability:** ✅ In Stock

## Summary

> ⚙️ Elevate your CNC game with precision and power that never quits!

## Quick Answers

- **What is this?** CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor by cnctopbaos
- **How much does it cost?** 5367287₫ with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.vn](https://www.desertcart.vn/products/245713294-cnctopbaos-engraving-machine-rotary-4th-axis-cnc-router-rotation-fourth)

## Best For

- cnctopbaos enthusiasts

## Why This Product

- Trusted cnctopbaos brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Versatile Clamping:** 4-jaw self-centering chuck supports internal and external diameters from 2mm to 90mm for diverse projects.
- • **Power Meets Control:** Hybrid Nema23 stepper motor with 12kg.cm torque ensures smooth, reliable rotation under load.
- • **Precision Perfected:** Experience zero backlash with a gapless harmonic gearbox delivering 0.018° step accuracy.
- • **Durable Craftsmanship:** High-quality aluminum alloy body with anti-rust coating guarantees longevity and stable operation.
- • **Tailstock Flexibility:** Movable MT2 tailstock with 45mm expansion stroke and axial locking wrench for precise workpiece support.

## Overview

The CNCTOPBAOS 4th Axis Rotary Engraving Machine features a gapless harmonic gearbox with a 100:1 reduction ratio for ultra-precise 0.018° step rotation. Powered by a robust Nema23 stepper motor delivering 12kg.cm holding torque, it offers smooth and stable operation. Its 100mm K12 4-jaw self-centering chuck accommodates a wide range of clamping sizes, supported by a durable aluminum alloy frame and a versatile MT2 tailstock for enhanced workpiece stability. Ideal for professionals demanding precision and reliability in CNC routing and engraving.

## Description

Full description not available

## Features

- Specifications of 4th Axis: Center height: 65mm / 2.56 inch; Total height:; 105mm 4.13 inch; Angle: 0.018°/step; Gearbox model: 17-100; Reduction ratio: 100:1; Base Material: Aluminum alloy; Size: 260x110x105mm / 10.2x4.34x4.13 inch; Weight: 7KG / 15.4 LB
- Specifications of Stepper Motor: Hybrid Nema23 Stepper Motor; Phase: 2-phase; Size: 57x57x56mm; Step Angle: 1.8°; Holding Torque: 12kg.cm/178oz-in/120N.cm; Rated Current:3A; Shaft dia:8mm; 4 Lead Wires: A+ to Red ; A- to Green ; B+ to Yellow ; B- to Blue
- Specifications of Chuck: K12-100 4 Jaw self-centering chuck; Diameter:100 mm 3.93 inch; With four Anti-claw and Wrench; Max input torque: 60N.m; Max Speed: 3500 R/min; External jaw clamping range: 30-80mm 1.18-3.15 inch.; Internal jaw clamping range: 2-30mm 0.08-1.18 inch; Internal jaw jamming range: 30-90mm 1.18-3.54 inch
- Features: Adopting gapless harmonic gearbox,with higher precision, no backlash, high rigidity, high efficiency, stable structure, smooth operation; Made of high quality aluminum alloy, anti rust coating process, fine workmanship, excellent forging process, and long service life
- Specifications of Tailstock: Morse Taper 2 Live Center Movable MT2 Tailstock; Center Height: 65mm 2.56 inch; Expansion stroke: 45mm 1.77 inch; Stretch distance: 50mm 1.97 inch; Top tip: Activity type; With Axial locking wrench for tailstock; Weight: 2.5 KG 5.5 LB

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Thread Size | 1-1/4"-10 UNC |
| Capacity | 3.93 Inches |
| Included Components | Wrench |
| Manufacturer | Changzhou Rattm Motor Co.,Ltd |
| UPC | 619191730193 |
| Part Number | S23 |
| Item Weight | 22.5 pounds |
| Package Dimensions | 20.5 x 11.4 x 8 inches |
| Item model number | K12-100mm 100:1 |
| Is Discontinued By Manufacturer | No |
| Style | 4 Jaw 100:1 |
| Item Package Quantity | 1 |
| Handle Material | Aluminum |
| Cutting Diameter | 100 Millimeters |
| Batteries Included? | No |
| Batteries Required? | No |

## Product Details

- **Brand:** CNCTOPBAOS
- **Material:** Aluminum
- **Item Diameter:** 100 Millimeters
- **Item Weight:** 10.23 Kilograms
- **Compatible Devices:** Milling Machine, Lathe

## Images

![CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor - Image 1](https://m.media-amazon.com/images/I/71DhBbRUOhL.jpg)
![CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor - Image 2](https://m.media-amazon.com/images/I/71be6GafiJL.jpg)
![CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor - Image 3](https://m.media-amazon.com/images/I/71-IpynzbbL.jpg)
![CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor - Image 4](https://m.media-amazon.com/images/I/817QoOoVDfL.jpg)
![CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor - Image 5](https://m.media-amazon.com/images/I/71AGYmoIqXL.jpg)

## Available Options

This product comes in different **Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Good quality for the price, got it working on a Tormach/PassPilot
*by S***N on November 3, 2021*

Excellent packaging and nice workmanship. The NEMA23 stepper at the end is open to the elements (coolant), and the flimsy cables are unprotected, both of which can either be accepted or fixed by adding a small enclosure that hides the stepper and cable nuts, plus an armored cable. Anyone with a use of a 4th axis can probably devise such an enclosure in an afternoon. the chuck is a standard low-cost CN-made 4" chuck.The electro-mechanical specs (stepper, gear ratio, and such) seemed to be the substantially the same as the 4" from TM, so I was hoping that, after configuring the DIP switches on TM's 4th axis integration kit appropriately for the TM 4" but lower current, and in PathPilot's UI selecting the 4" 4th axis option, it would work out of the box. It stepped just fine, but the angles were off by a bit. I had to adjust the SCALE value in the PathPilot 4th axis config file from 141.666666 (which, according to my math, would be appropriate for a 51:1 gear ratio) to 138.888888 (which is correct for a 1:50 gear ratio). If you don't know how to do that, google it in the LinuxCNC forums. If that's too much wizardy, then this product is probably not for you.The stepper is considerably less powerful than TM's NEMA34 stepper, but for my purpose--which can be best described as indexing rather than 4th axis continuous machining--it works just fine. I'm pretty sure there would be enough torque for light machining (maybe a 1/4" endmill and light cuts in AL).I haven't used the tailstock yet.For my first experiments, I put the whole thing into my 5" vise, which has just enough travel and was already properly aligned.

### ⭐⭐⭐ Unlucky with product, great Amazon support
*by B***. on August 27, 2019*

Pro.The second unit I received worked very well. The machine has much more torque than I expected with zero detectable back-lash although this is based on fairly crude measurements.. I purchased the unit to work on 3/8 inch aluminum rod on a proper industrial milling machine and I feel that it would handle larger diameter steel rod if required.The chuck and steady seem quite good quality.The unit is easily controlled from a simple Arduino micro-processor using one of several freely available libraries and examples, I think I used a library called SpeedyStepper which allows quite elaborate movements.It will conveniently mount in a standard milling machine vise so there is no need to align it on the mill table if you have a good quality vise and you prefer to keep it in place..Cons.If the first unit had operated properly I would have given 4 stars. Unfortunately it sounded during rotation as though a gear or bearing was grinding badly.. Amazon's return process worked beautifully and I had a replacement unit in a couple of days with plenty of time to return the original unit at no cost through a Kohl's store.The unit is not finish machined so its inherent precision is suspect but this will not matter for most applications.The supplied instructions are not great. In the end I discovered that putting the machine into operation was not very difficult but better instructions would have saved a lot of time. Do not forget that you will need a fairly capable driver to operate the unit..This unit does not have a hole all the way through the body so you cannot work on long stock. About 5 inches would be maximum length.You cannot control this unit directly from a 4th axis output on an industrial grade milling machine. It is more correctly descried as an indexer rather than a 4th axis although some simple CNCs that use stepper motors rather than servos may be able to drive it directly. I am working on this with a CNC technician..

### ⭐⭐⭐⭐ Pretty good little rotary.
*by J***N on November 13, 2019*

The first one I received had a ton of backlash and was really disappointing after reading the other reviews. While I was waiting for the replacement to arrive I decided to look inside and see what was wrong. When I removed the motor I found the two set screws on the motor shaft were loose so I tightened them, put it back together and measured this to only have 3 arc minutes of backlash. Happy with that I kept the original and sent the second one back unused. This didn't come with any directions so I had to go the internet for wiring the motor: A+ red, A- green, B+ yellow, B- blue. I have this running at 27500 degrees/minute which I think is pretty impressive considering the 50:1 reduction. To achieve that its running on 50 volts, at 2.84 peak amps. I really don't know if 50v is ok for this motor since there is no documentation with it, but that's what my system runs at so that's what its getting. My only other gripe is that this should really come with a 4 jaw chuck in stead of 3 since it will predominantly be used on routers.

## Frequently Bought Together

- CNCTOPBAOS Engraving Machine Rotary 4th Axis,CNC Router Rotation Fourth A-axis 4 Jaw K12-100mm Chuck Dividing Head,Gapless Harmonic Gearbox Reducing Ratio 100:1 w/ 65mm Tailstock Nema23 Motor
- PGFUN DIY CNC Touch Probe XYZ Axis 3D Digitizing Edge Finder 3-Coordinate Measuring Sensor Kit with 6 mm Shank & 2.0 mm Tungsten Steel Ball Tip
- STEPPERONLINE CNC Stepper Motor Driver 1.0-4.2A 20-50VDC 1/128 Micro-Step Resolutions for Nema 17 and 23 Stepper Motor

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.vn/products/245713294-cnctopbaos-engraving-machine-rotary-4th-axis-cnc-router-rotation-fourth](https://www.desertcart.vn/products/245713294-cnctopbaos-engraving-machine-rotary-4th-axis-cnc-router-rotation-fourth)

---

*Product available on Desertcart Vietnam*
*Store origin: VN*
*Last updated: 2026-03-04*