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Rotary Tool (Dremel-type) Product

Overview

A rotary tool is a small handheld power tool that spins interchangeable bits at very high speed from a pen-style grip. Where a drill turns slowly with high torque, a rotary tool does the opposite: it runs tens of thousands of rpm with little torque, so abrasive and cutting accessories work by surface speed rather than force. One body accepts cut-off discs, grinding stones, sanding drums, engraving cutters, polishing wheels and wire brushes, which makes it a general-purpose tool for hobby work, repairs, model-making and detail finishing.

The tool is built around the High-Speed Motor, a compact motor whose shaft runs in two bearings and carries a cooling fan. Accessories mount through the Collet & Nose Cap: a split collet is dropped over the bit shank and a threaded nose cap squeezes it tight. The Spindle Lock Button pins the spindle so the cap can be loosened with a single Collet Wrench from the Accessory Kit kit. Speed is set on the On/Off & Speed Dial and held steady by the electronics under load.

How it works

Pressing the switch sends a setpoint to the Variable-Speed Board. Because abrasive accessories slow down as they bite, the board reads actual motor speed from a Tacho Sensor and trims drive to hold the dialled speed, so an engraving cutter does not bog down mid-cut. The motor's fan pulls air through louvres in the Housing & Grip, whose slim overmoulded grip lets the tool be held like a pencil for control.

Power is supplied through the Power Supply block, which is either a mains Power Cord on corded models or a Battery Pack pack of three Li-ion cells with a protection board on cordless ones. The collet system is what makes the tool versatile: a single spindle accepts any shank that fits the chosen collet, so swapping from a Cut-Off Disc on a Accessory Mandrel to a Grinding Bit takes seconds. Run-out is kept low by the front spindle bearing and a true-running collet, which matters because tiny bits at 30,000 rpm amplify any wobble into chatter and broken tips.

Build & assembly graph

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Bill of materials

8 top-level lines · 42 rows shown · 120 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 High-Speed Motor 6 parts rotary-tool-motor 1 28 assembly
1.1 Stator Assembly 3 parts stator-assembly 1 3 assembly
1.1.1 Stator Core (laminations) stator-core 1 part
1.1.2 Copper Winding copper-winding 1 part
1.1.3 Slot Insulation stator-insulation 1 part
1.2 Rotor Assembly 4 parts rotor-assembly 1 19 assembly
1.2.1 Rotor Shaft rotor-shaft 1 part
1.2.2 Rotor Core rotor-core 1 part
1.2.3 Neodymium Magnet neodymium-magnet 16× 16 part
1.2.4 Ball Bearing ball-bearing 1 part
1.3 Copper Winding copper-winding 2 part
1.4 Motor Housing motor-housing 1 part
1.5 Ball Bearing ball-bearing 2 part
1.6 Cooling Fan rotary-tool-fan 1 part
2 Collet & Nose Cap 4 parts rotary-tool-collet-nose 1 4 assembly
2.1 Output Spindle rotary-tool-spindle 1 part
2.2 Split Collet rotary-tool-collet 1 part
2.3 Collet Nose Cap rotary-tool-collet-nut 1 part
2.4 Ball Bearing ball-bearing 1 part
3 Spindle Lock Button rotary-tool-shaft-lock 1 part
4 Variable-Speed Board 5 parts rotary-tool-speed-board 1 66 assembly
4.1 Bare PCB pcb-bare 1 part
4.2 Microcontroller mcu 1 part
4.3 SMD Passive (R/C/L) smd-passives 60× 60 part
4.4 Tacho Sensor rotary-tool-tacho-sensor 1 part
4.5 Connector connector 3 part
5 Housing & Grip 3 parts rotary-tool-housing 1 3 assembly
5.1 Housing Shell rotary-tool-shell 1 part
5.2 Soft Grip rotary-tool-grip 1 part
5.3 Fastener Set fastener-set 1 part
6 On/Off & Speed Dial rotary-tool-switch 1 part
7 Power Supply 2 parts rotary-tool-power 1 6 assembly
7.1 Power Cord rotary-tool-cord 1 part
7.2 Battery Pack 3 parts rotary-tool-battery 1 5 assembly
7.2.1 Li-ion Cell, 18650 li-cell-18650 3 part
7.2.2 BMS Board bms-board 1 part
7.2.3 Connector connector 1 part
8 Accessory Kit 4 parts rotary-tool-accessories 1 11 assembly
8.1 Accessory Mandrel rotary-tool-mandrel 2 part
8.2 Cut-Off Disc rotary-tool-cutting-disc 5 part
8.3 Grinding Bit rotary-tool-grind-bit 3 part
8.4 Collet Wrench rotary-tool-wrench 1 part

Sourcing — likely vendors

Companies that make this · indicative price $30–$800 · MOQ & lead are typical
VendorHQSpecialtyMOQLead time
stanleyblackanddecker.com ↗ New Britain, US Tools (DeWalt, Craftsman) 500 units 6–12 wks
bosch-professional.com ↗ Leinfelden, DE Power tools 500 units 6–12 wks
🇨🇳Techtronic
ttigroup.com ↗
Hong Kong, CN Tools (Milwaukee, Ryobi) 500 units 6–12 wks
🇯🇵Makita
makita.com ↗
Anjo, JP Power tools 500 units 6–12 wks
🇨🇭Hilti
hilti.com ↗
Schaan, CH Construction tools 500 units 6–12 wks

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