Introduction: Dremel Style Rotary Tool

I saw someone building a Dremel Style Rotary Tool on a YouTube tutorial and as I don't have one I thought why not give it a try. I'd also never used Banggood before so it was an experiment in how long it takes to ship small items from China to the UK... about 3 to 4 weeks as it goes... good job I wasn't in a hurry.



  • 10pcs AbrasivE-mounted Stone Rotary Tool 1/8 Shank For Dremel £2.61
  • Drillpro SW-B2 6pcs HSS Circular Saw Blades Set Titanium Coated Saw Blade for Rotary Tools £3.79
  • 5Pcs Mini Round Red 2 Pin SPST ON-OFF Rocker Push Button Switch £1.88
  • 380 DC Motor @ £4.72
  • 8pcs Small Electric Drill Bit Chuck Set @ £2.50
  • 2A DC-DC Adjustable Step Up Power Module @ £1.16


  • TP4056 18650 Lithium Battery Charger Board @ £0.99
  • 18650 Battery Holder @ £1.03
  • 2pcs 1" PVC Pipe End Cap @ £1.75
  • 1" PVC Pipe £5.38
  • M2 Pan Head Machine Screws @ £1.25
  • PVC Flat Engineering Plastic Sheet 2mm Thick @ £2.70

The things I had kicking about

  • Drill
  • Screwdrivers
  • Saw
  • Super Glue
  • Hot Glue
  • Soldering Iron & Solder
  • Balck and Red Wire
  • 18650 cell
  • Multi meter

Step 1: Components

I assembled everything before I started, nothng worse than getting half way through your build and then having to wait for 2 weeks whilst you wait on the last thing arriving.

Step 2: PVC Work

  1. I started by lining everything up in order to get an idea of how much pipe i would need

    1. Motor
    2. On/Off switch
    3. Step up
    4. Battery Holder
    5. Charger
  2. I then cut the pipe to the correct size

  3. I cut 2 discs out of the 2mm PVC sheet, both with a 10mm hole in the middle

    1. One the same as the Outside Diameter of the Pipe
    2. The other just smaller than the inside diameter of the pipe
  4. 3 holes were cut on the pipe; 2 where the air vents are on the motor and one where the switch will be fitted

  5. 2x 2mm holes were drilled in the larger of the PVC disk and it was then screwed to the top of the motor

  6. Wires were then soldered to the motor terminals which were then threaded through the smaller PVC disk and this was then hot glued in place (this set up protected the terminals from the other electrics that would be fitted adjacent to the motor)

Note: I had to experiment which way the motor rotated and fix the red and black wires to the correct terminals fitting the wrong way round would mean the saw blades that I would fit later would not cut as the teath would be facing the wrong way.

Step 3: Electrics

  1. I soldered the TP4056 USB charger board to the 18650 cell holder

  2. On the other side of the holder I soldered the MT3608 Step Up board

  3. Inserting the 18650 cell into the holder I connected the Multi meter to the step up and adjusted it so that the reading went up from 4v to ~11v

  4. I soldered a long piece of red wire to one of the switch terminals and threaded the witre back through the pipe so that it came out of the bottom I also pushed the motor into the top of the pile so that the black wire also came out of the bottom of the pipe

  5. I then soldered the relevant red and black wires to the corresponding positive and negative connectors on the Step Up converter

  6. I pilled the red wire from the motor out of the hole made for the switch and soldered it to the otger switch terminal before pushing the switch in to place

  7. Finaly I superglued the PVC disk that was screwed to the motor onto the pipe

Step 4: Finishing Off

  1. I slid one of the PVC end caps onto the bottom to stop all of the electrics falling out

  2. I drilled a 20mm hole in the top of the other end cap

  3. Finaly I fixed the cuck to the motor shaft and slid the end cap with the hole in it onto the top of the pipe.

To charge the device I just need to slide the bottom cap off and plug a Micro USB into the TP4056, when the light shines blue I'm good to go

Step 5: Leasons Learned

I have 3 things that I take away from this:

  1. The torque on a 380 DC motor is not great and with any resistance the tool comes up against it will basicaly stop it dead in it's tracks

  2. Understanding PVC Pipe diameters is key, I purchased 2 other pipe diameters before I got hold of the right size (the inside diameter of a 1" pipe fits a 380 motor perfectly)

  3. I spent in total £29.76 - for the same amount you can buy a 135W Draper (£28.98) or a 135W VonHaus (£29.99) and if i need a tool for anythng more solid than styrofome I probably will.

Conclusion: it's not about usibility or cost, it's all about building it yourself.