| Archive for The Unofficial Mamod and Other Steam Forum The Original Unofficial Toy Steam Forum Established 2006 The biggest, most popular steam forum around! Accept NO imitations! We have a growing community of regular posting members who chat about all aspects of toy and model steam. |
| hansdampf |
A mini power plantHi to all,here I'd like to show what one can do on boring foggy Sunday afternoon, with parts out of the leftover box. And it really works on twisting with fingers. 
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| Reid |
Teach me German for "I want to see it on YouTube"?
http://www.youtube.com/watch?v=5iyRwaMjzDE (this is the very first time I spun this special, small motor other than by fingers) See also, #10B and #10C? And -show me your generator's construction? I'm excited by your precision interests That is a very pretty housing and setup for the tiny system. I like the brass. I like your good taste. |
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| Steve_S |
Looks good! | ||
| hansdampf |
Thank you for the comments.
Reid, I'm not yet familiar with YouTube, but I will get soon. Nice videos from your HOG and the dynamo/LEDs. For the construction of the generator I have no plans or drawings, it is a small DC-motor out of an defective CD-ROM. Because such motors produce a chopped DC usually with low current, LEDs can be lit perfectly. |
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| mc_mc |
It looks somewhat neater than my attempt:
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| hansdampf |
...but yours work the same way. Form followes funktion. What type of LEDs do you use for the flashing/color changing effect- looks great.
And the DISCO video- very good idea! |
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| mc_mc |
I used these: http://www.ledshoppe.com/Product/led/LE1008.htm
20 for $7 US with free worldwide postage. There are some bargains on that site. I found I could run about 12 of them off the little generator (a tray eject motor from on old CD ROM drive.)
The full thread is here: http://modelsteam.myfreeforum.org...25.html&highlight=mamod+disco |
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| Reid |
I bought three of them online. They are brushed, Mabuchi motors. I thought, and I may be right (I don't know), that my motor was once meant for cassette tape capstan drive. The motor runs slowly but with fair torque on 1.2V. It will light a high-current (20ma) white LED with a finger-spinning, like your motor does too. My motor has tiny, low-friction brushes. The winding has high DC resistance. It is good for the LED duty, but much more than that! So, we are "on the same page". Good to learn of your parallel success! |
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| Reid |
Thanks for the great demonstration, mc! |
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| Mister Occlusion |
Nice little unit. Quite inspiring 
have you worked with stepper motors? |
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| hansdampf |
Hi there,
I haven't used stepper motors till now, because I wouldn't know from which equipment I can get one off
What would be the advantages of a stepper motor in comparison with a "normal" electro motor? |
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| mc_mc |
Get hold of an old printer. The print head is moved by a powerful stepper motor and there maybe be another for the paper feed.
The advantage of a stepper motor is that there are more coils inside so you have 3 or 4 power generating units in one so you can get much more power from it. The disadvantages are: Higher torque needed to spin it up. A rectification circuit is needed to deliver a steady dc voltage. As ever there's lots of info on the forum: http://modelsteam.myfreeforum.org/about6261.html&highlight=stepper I'm waiting to get a dodgy old printer myself so I can have a go with one of these. |
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| Reid |
I presume: the stepper motor to be a magneto at heart, same as the famous flywheel magneto of the Model T Ford. Now, this stepper "magneto" usually contains, from what I read, two independent windings, both center-tapped, and not in exact phase with each other. Both windings are of relatively high turns-count, (and of quite-fine wire, due to the space limitations), therefore, a high inductance results as the rotating rare earth magnets pass the multiple windings, and there is there is made, a high-ish DC voltage/pressure for a given shaft speed. With these independent, but interconnectable, C.T. windings, a fair number of configurations are possible in converting the stepper to generator duty, to afford a higher current machine at a lower voltage potential, or the other way around. But I don't know for sure because I am not yet physically experienced here. |
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| mc_mc |
Some more good links:
http://en.wikipedia.org/wiki/Stepper_motor http://www.reuk.co.uk/Stepper-Motor-Basics.htm |
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| johnreid |
The stepper motors that I bought, and are similar to PSMs, were pulled from CNC machinery and a bit larger than those I see in printers. 4 sets of coils are in mine, and they do produce a lot more power than the simple electric motors, however the simple electric motors probably do enough to satisfy most desires as it seems that the most common use is to light 1 lamp and LEDs consume less power than an incandescent bulb. | ||
| Mister Occlusion |
I pulled a couple really nice steppers from very old 5.25" floppy drives.
These are the big square motors like Mr PSM uses on his fine generators
I ripped apart a 4-6 year old HP deskjet a few weeks ago, and I do not believe the motors in it will be of practical use. I *did* get some great springs and solid steel bar from it, for which I have no present use but someday hope to... Laser printers will also have steppers in them. But likewise, the one printer that I ripped apart (laserjet IIIP) had a motor of such heft and stiffness of shaft that it would not be suitable. |