Motor (Back And Forth)

Decorating By Torts Updated 2 Mar 2013 , 2:47am by Nannuu

Torts Posted 3 Oct 2012 , 7:47pm
post #1 of 9

I need some help! I'm making a cake for my friend's rehearsal dinner- they wanted something "New Orleans" so I'm doing the New Orleans streetcar. I have the mini lights that I'm going to use as the headlight in front and in the street lamps, but I would LOVE if I could make it move back and forth. All the motorized cake posts I have found have been rotating- I just want forward and reverse in a straight line. The streetcar is made of RKTs and will probably weigh about 1 lb 8 oz when decorated. It's 10 inches long, about 4 inches high and 3 inches wide. I don't know how much power it needs to move this, how to stop it and reverse directions, etc. Can anyone help? Thanks in advance!

8 replies
BakingIrene Posted 3 Oct 2012 , 8:37pm
post #2 of 9

You need a control unit as well as a motor--that's how you get the back and forth part. Look on ebay.

Torts Posted 3 Oct 2012 , 9:45pm
post #3 of 9

Okay, thank you so much! Do you think I'd be able to find that at a hobby store? They were closed today but I was going to go by there tomorrow. I just have to have it for Friday night, so eBay really isn't feasible, unfortunately. RadioShack doesn't sell them, but any suggestions are welcome. Thanks again!

BakingIrene Posted 4 Oct 2012 , 12:25am
post #4 of 9

You will have to go to a model train shop to get the motor and controller. They will tell you how to use it.

Evoir Posted 4 Oct 2012 , 12:59am
post #5 of 9

Yep - try a hobby store that sells model train components.

Or marry an engineer icon_wink.gif

Torts Posted 4 Oct 2012 , 4:12pm
post #6 of 9

Thanks y'all. I tried three hobby shops and they all said they couldn't help icon_sad.gif I laughed about marrying an engineer- my brother is an electrical engineer and said "go buy a motor." Not helpful, haha! My dad does model trains obsessively and didn't know how to achieve what I wanted. So I was 0 for 5 on "experts." I think they get thrown off when I explain it is for a cake. I did see a "beginner" tutorial online for a robot that reverses directions automatically when it hits an object (perfect!) but I stopped reading when it got into solderless breadboards and robot lingo. Sigh. I had such high hopes! Thanks again. Maybe I'll figure
it out for the next cake!

BakingIrene Posted 4 Oct 2012 , 4:46pm
post #7 of 9

Well you can tell the family engineers that the automated back-and-forth comes from the moving object hitting a pair of electromechanical switches. These switches would be imbedded at both ends of your streetcar track They send a signal to the motor to reverse direction, and this runs for as long as the power is on.

You would build all the electrical stuff onto a board or dry pastillage platform that has to sit a little above the actual iced cake. The wire connections are taped together with electrical tape. You build the electrical stuff first, and then cover the rest of the track with the sugar details.

This is simple stuff if you can find the right bits and pieces on ebay, and there are instructions galore online. Maybe you can work on this in time to blow the socks off your dad for his birthday...

Torts Posted 8 Oct 2012 , 10:21pm
post #8 of 9

That's a great idea! Haha his birthday is in September, so I'll have a full year to work on it. No one would believe me that this could be done with a cake. Thank you so much for all of your help!

Nannuu Posted 2 Mar 2013 , 2:47am
post #9 of 9

Back and forth motion is really pretty easy.  How far exactly do you want the car to move?  You don't need circuits and switches for all back and forth motion.  If you can post the distance I can mock something up that may help.

Quote by @%username% on %date%