HDD grinder with speed control

HDD grinder with speed control

Surely, most people have old hard drives lying idle in their bins. From it you can make a necessary and useful thing for sharpening knives, scalpels and other objects - a miniature grinding machine with a wheel rotation speed controller.

Will need



You will also need wires, casings for insulation and a few other little things.
The three main components are:
Hard drive in any condition. It is difficult to burn out the engine in it, so it is 100% suitable. And we will have a purchased board with a control driver.
HDD grinder with speed control

The motor in the HDD is three-phase, brushless and very powerful. It simply won’t operate on DC power and to start it you will need a controller or driver for controlling a three-phase motor.
HDD grinder with speed control

To control the controller you need a speed regulator, it looks like this:
HDD grinder with speed control

Assembling a grinding machine from a hard drive


So, let's open the hard drive. Here you will have a problem - you will need specialized screwdrivers, since the bolts and screws are non-standard. I advise you not to worry and buy, or rent, a set with such screwdrivers.
HDD grinder with speed control

In general, we unwind everything: both from above and from below, since nothing other than the installed motor is needed.
HDD grinder with speed control

We remove the board, leaving only the contacts for connecting to the motor. Now look: motors in hard drives can have either three or four pins.
HDD grinder with speed control

It all depends on the method of switching on the windings. Somewhere they are connected according to the “star” circuit, and somewhere according to the “triangle” circuit. Both options will suit us.
HDD grinder with speed control

Except that for a three-pin HDD everything is clear with the phases - “ABC”, but for a four-pin HDD you will have to look for the phases using a tester. We will not need the middle or common wire - it will not be used.
HDD grinder with speed control

We connect the wires to the motor from the controller, insulate them and secure them with a metal jumper (you can cut it out of a tin can).
HDD grinder with speed control

Using the same jumper, we fix the controller itself on the side of the rotating disk.
HDD grinder with speed control

To cut a circle from sandpaper, remove the disk itself from the HDD motor. Apply it to sandpaper, trace it on the back side with a pencil and cut it out with regular scissors.
It's time to glue the cut out circle onto the metal disc. It's all attached with double-sided tape. Your circle will not go anywhere, and it will be easy to change it when it wears out.
HDD grinder with speed control

Screw the disk.
HDD grinder with speed control

From the cover we make a protective casing for the controller. We cut out a semicircle with a Dremel.
HDD grinder with speed control

And we make a protective casing from a piece of tin so that wear products do not fly onto the controller.
The tin strip is soldered to the hard drive cover with a soldering iron.
HDD grinder with speed control

We collect everything. We connect the speed controller.The connection is made using a pin connector. These two modules are specially created for each other and are actively used in modeling.
HDD grinder with speed control

We connect the 12 V power supply. Use the regulator knob to adjust the speed of rotation of the disk. Everything should work without configuration.
HDD grinder with speed control

With the help of a PWM controller, the speed is adjusted very smoothly and within wide limits.
Now you can sharpen either metal or plastic. This useful design will definitely find use in your home.
Thank you for your attention!

Watch a video of the grinding machine in action



Original article in English
come back
Comment
  • bowtiesmilelaughingblushsmileyrelaxed relaxedsmirk
    heart_eyeskissing_heartkissing_closed_eyesflushedrelievedsatisfiedgrin
    winkstuck_out_tongue_winking_eyestuck_out_tongue_closed_eyesgrinningkissingstuck_out_tonguesleeping
    worriedfrowninganguishedopen_mouthgrimacingconfusedhushed
    expressionlessunamusedsweat_smilesweatdisappointed_relievedwearypassive
    disappointedconfoundedfearfulcold_sweatperseverecrysob
    joyastonishedscreamtired_faceangryragetriumph
    sleepyyummasksunglassesdizzy_faceimpsmiling_imp
    neutral_faceno_mouthinnocent
3+three=
Comments (8)
  1. Vasya
    #1 Vasya Guests 10 May 2018 17:07
    1
    And all this despite the fact that the computer's power supply supplies the disk with a constant voltage of 5 and 10 volts... Good to hang noodles!
  2. Sashka
    #2 Sashka Guests 26 May 2018 07:49
    4
    Vasya..., there 12V power is supplied, and the controller in the disk converts it into three-phase voltage... Read the materiel, you will be smarter!
  3. DronSF
    #3 DronSF Guests 8 January 2019 15:59
    0
    How much power does the PSU need? I have 1A and the disk does not rotate, but barely jerks back and forth
    1. DronSF
      #4 DronSF Guests 8 January 2019 16:05
      0
      If you help with your hand, it accelerates.
    2. DronSF
      #5 DronSF Guests 8 January 2019 16:27
      0
      There is a sticker on the hard drive case 5v 450mA and 12V 215mA.
    3. DronSF
      #6 DronSF Guests 8 January 2019 22:42
      0
      I took another disk with parameters 5/12V 700/800mA. It worked as it should.
  4. Guest Andrey
    #7 Guest Andrey Guests May 1, 2019 09:22
    0
    Why a vegetable garden? no need to throw out the insides, it starts perfectly. I pulled out the magnets, bent the head into the “pocket” so that it wouldn’t get in the way, and everything started fine from the standard power supply from the computer. A speed regulator, well, if anyone needs it, you can install it. Although why is it on sandpaper, but in fact it is sandpaper. It is possible to burn metal using factory emery, if you have the desire).
    1. Goil
      #8 Goil Guests 24 December 2021 17:59
      0
      The problem is that the propeller motor controller is tied to the head controller, if they cannot read data from the pancakes, then the propeller is disabled