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Motors for Scratch builds

1987 Views 7 Replies 6 Participants Last post by  altterrain
I rather enjoy scratch building models, but my knowledge of motors is woefully lacking. /DesktopModules/NTForums/themes/mls/emoticons/blush.gif.

My general requirements are usually a relatively small train, generally something that would at the most be compareable to a bachmann porter in size and strength, though i have built a couple smaller and a couple bigger ones. The motors need to have a tolerance for voltages up to 22-24 volts or i need a way to protect them from overloading at such voltages.

M current project is a fireless steam locomotive that would be required to pull 4-5 cars at the most. 

Do you have tips for which motor i should choose for this project? and tips for choosing the proper motor and source of motors for future projects.

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You could go the route that ITUNCLE uses. Look for the thread on scratch-power. OR start with a loco from ebay and customize from there. OR do go the route that I'm choosing: Just jump in with both feet using a couple of surplus 12v motors from the local electronics store. One other thought that I may try as well: Harbor Freight frequently puts in 9.6 and 12v drills on sale for $10-$15. Next time they do, I'm going to pick one up and disassemble. THAT should have plenty of torque.


Woud a 12 volt motor be able to handle 24 volts?

Not for very long  :)

All the motors that I have worked with, both big and large, AC or DC, are rated at the max voltage rating.  So a 12v motor will only handle 12v.  24v will handle a max of 24v and so on.

After that, I'm afraid I don't remember enough of my high-school electronics to be of much more use.  I know there are ways to build circuits to protect/limit the amount of voltage going to your  motor.  Hopefully someone else on the forum can be of help here.

The main problem is not the motor -but how you connect the motor to the axles... It is very easy to build a potential divider to allow a 12Volt motor to run on 24Volts. You use two very large wattage resistors of equal value, and take the voltage to the motor from the mid point. Here is a link to MFA -who supply most of the equipment that I use:



The place I usually deal with is called the Surplus center and I believe the web site is WWW.surpluscenter.com they carry alot of 12 to24 volt motors, gear drive ,worm drive, direct drive, hope this helps too, Take care and Good luck
Besides, at 24v, your 12v motor will be going REALLY fast.

However, if you're worried about running a 12v motor on your layout, you'll find you run the loco well below 12v to get a nice speed.
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