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As long the VE-180, nicknamed "Ultimate Cooker Model 230" isn't done yet, I've tried to create something more weird:

http://www.youtube.com/watch?v=SF76pZEmAVU

Please excuse the bad quality, I filmed that using my mobile phone...

The chapter 2 would be from the ordinary PC HDD, unfortunately, it can't be done now...
I have a spare PC PSU, two old potentiometers from school (56 MΩ and 2 MΩ one), and some harddisk that will arrive from post soon enough I hope .
You surely know how the molex HDD connector looks like. It has 4 pins, +5V, gnd,gnd,+12V. I have cut the 12V wire into two (leaving the molex connector as it is), the 1st end I've soldered to the middle of the 56MΩ rheostat, and the 2nd end is soldered to the most-left rheostat pin (the potmeter has 3 pins). So the connector should work if I've soldered properly. I have tested the connections using an ordinary multimeter:

The wire coming from the PSU itself, into the middle rheostat pin, has resistance Ω = 0.00, which is good (the connection is soldered properly).
The wire soldered to the left pin, that has output into the molex connector is soldered properly too (Ω = 0.00).
But when I tried to measure the resistance of the middle and left pin itself (normal thing what potentiometers are doing ), i have been shown "1 ." which means there can't be any resistance to be measured (non-conductor)... Plugging PSU into mains won't help, as you surely know you do not need electricity for measuring conductor resistance. Also I tried to invoke a short circuit by shorting the +12V pin (coming right from the left rheostat pin) by ground... no spark, no power loss in PSU, no nothing. And when I tried that in the remaining 2 molex connectors, which aren't "touched" by the potentiometers, I've seen a little spark with immediate PSU power-off (it is still working) So, the potentiometers are bad

And they could be pretty strong, I do not know if i could slow the 5200 RPM harddisk to at least 50 RPM with an 100Ω potentiometer

Comments welcome.

Regards
inflater

The "Ultimate Cooker" would be ready tomorrow I think... I have discovered that the alternating current doesn't perform the electrolysis, so the model name will be from "VE-180" to "UC-230"; or... would you guess the name for me?

//EDIT:
http://www.freepatentsonline.com/4913047.html

Do will they patent CPU fan gramophones too?

Regards
inflater

I've got myself a very old 90 MB harddisk from early PC/AT. But I ran on some silly problems:

- I have removed the disk head, because it was taking too much "room" and was unsuitable for my project. Before removing, all was al'rite. Now the disk platter would spin, but after 5-6 seconds the motor will brake itself for cca 1-2 seconds, and fire up again. It would be good when platters would spin continously... What should I solder, or earth, or short (:lol:) to make the platters "believe" that the disk head is present and working?

- Can I slow the motor down (at least barely) using two 100Ω potentiometers? I had one 56 MΩ and one 2 MΩ, but I think they were dead even before soldering to the molex connector... Also I have one 500Ω, but I think it would be hopeless if the motor was still spinning very fast (above 900 RPM)...
Or is it normally possible to connect it at +3.3V/-5V (from original molex specifications +5V/-12V)?

- The motor is spinning counter-clockwise, i'd like to spin the platters clockwise. If the motor would be simple enough, all I would have to do is swap the polarity, but that wouldn't help in my case I think... Is there any possibility of switching direction on a HDD motor without altering the chassis itself?

Regards
inflater

Greetings,
well, it's like this:

I made my own "air conditioner" some time ago. It was, and still is a CPU fan put in a box.
There are three wires coming from the fan, a yellow, black and a green one. I have read that the green wire
is reporting the speed to the PC or whatever. So I cut off the green wire and soldered the yellow wire to +12V and the black wire to ground. Voila, it's working!

My old ancient 90MB HDD had also the same three wires. They were coming from the platters to the head microchip or how should I call that black cockroach.
When I cut the head actuator cable from the microchip (of course without PSU on), all was OK except for the motor braking, so I have cut the green
wire into two, I thought that would solve the problem... And I said like if it wouldn't work I would solder them back to normal. The HDD didn't spin up, so I have "merged" the two wires temporarily
with my hands, and the HDD was spinning like before. I said OK, time to repair, but I forgot to shut off the PSU before I would take the wires away...

You probably know what happened; you're right, a short circuit. Damn!... That head control-beetle is broken alright, the platters aren't spinning.
I have shut the PSU eventually off, and I let it be for 5 minutes. After, I plugged the hard disk back again, turned on the power, and I noticed that
that microchip is beeping. It's a quiet short beep, the hard disk would make it right before the platters would spin. But now, it's beeping every 4 seconds and
the platters aren't spinning...

I'm left with only one choice: to rip the two remaining wires off (they are soldered as you can see in the pic) and put them on PSU like I did that with my CPU fan.
I hope it would work...

Here are the pictures:


Close-up


Regards
inflater

hmm..do I cut the red wire or the blue wire

My results...

Yeah, they were the correct wires I think... After applying 12V 300 mA, the motor didn't spin up and when I tried to spin it with hands, I noticed that the HDD doesn't want to spin, it will apply "handbrake" for the platters
So the green wire was useful, but no one knows for what now

My finger feels a bit itchy after been shorted with the black wire and the PSU 25 times...
I didn't use a PC PSU now, because I don't know where should I route the +5V.

//EDIT with PC PSU: Short and PC PSU switched off, using the molex connector output.
When using the ordinary 12V power supply, I think that the low current is the problem. I'm giving it 0.3A, it should be at least 2.3A for spin-up. Tomorrow, I will try to hook the HDD to the PC PSU's mainboard connector...