# Operating RPO



## kfrankl3 (Feb 27, 2008)

Silly question right now I am converting a Bachmann baggage car I got for cheap from ECLSTS to a operating RPO car. I'm planning to RC it so that either mail arm will swing out upon command. Furthermore I plan to put in a solenoid to "kick" out a mail bag too. Does anybody know of this having been done before? Or does anybody have any good ideas on how to make this? 
Thanks


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## Snoq Pass (Jan 2, 2008)

Not that I know of, but it sounds like an interesting idea though.


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## Richard Smith (Jan 2, 2008)

Either Lionel or American Flyer or both had just exactly what you're talking about many long years ago. An arm came out to grab a hanging mail bag while another was kicked out. You might check with some of the tinplate collectors to see how it was done. If you're lucky maybe you can even find someone that makes parts to restore the cars that you can use.


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## kfrankl3 (Feb 27, 2008)

sorry, I should have said has anybody done this in large scale?(I kinda wanna do something new) I actaully got the idea from the lionel mail car. I actually already have my plan kind of set out already. I'm going to hook up a motor to each arm so that it will pivot out the arm like the real thing. This will probably be the start of a mini builders log.


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## Torby (Jan 2, 2008)

You want it to prototypically scatter mail to the wind? 

(They hated when that happened.)


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## kfrankl3 (Feb 27, 2008)

lol, I figure having it scatter to the wind may be a bit much if i'm visiting somebody's layout (plus I wouldn't want to have to clean up little scale letters on my layout let alone another persons!).


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## Rod Hayward (Jan 2, 2008)

In the UK Traing did it years ago in OO. They had two roler levers that hung out of the bottom of the car and were actuated by a ramp in the track just ahead of the bag dispatch/retreval.


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## kfrankl3 (Feb 27, 2008)

thanks. I really like the simplicity of the design next to the lionel one. Do you know if anybody has posted video of that working. It's the british mail pickup method so it dosen't quite work for me but it's stillawesome.


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## Torby (Jan 2, 2008)

I think I'd start with a cheap servo. Nice motor and gear train for like $15. You can control it with a 555, or rip out the electronics and wire it to your liking.


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## kfrankl3 (Feb 27, 2008)

Torby, 
I'm sorry, could you please further explain. I always throught a 555 was a type of test circut. Could I activate it and deactivate it with say a toggle switch. 
Thanks!


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## Torby (Jan 2, 2008)

A servo, the old "analog" type, has 3 wires and runs on 4.5 to 6.5 volts. The wires are +, - and signal. 

The signal is a negative going pulse between 1 and 2 ms, usually 60 per second but not very critical. At 1ms, the arm is at one end of its throw, at 2ms, the arm is at the other end. You can position it anywhere in it's range by varying the length of the pulse. NE555 timers are handy circuits for anything time related. 

Of course, you can take the little pcb out and connect your switch to the motor any way you want.


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## Bob Pero (Jan 13, 2008)

American Flyer built the operating mail car. I have one packed away somewhere. It operated on a servo with springs. Somewhat violent in operation but a great device.


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## kfrankl3 (Feb 27, 2008)

Well I tried several solutions to the problem, and I've settled on and built it so that a servo will push out the arm. I discovered this really cool thing a a local RC shop called "servo savers". I've used the standard horn servo saver which wouldn't work well for my application, but they sold one that would fit onto a push rod (I'll try and see if I can get a maker this weekend). Well I've got it all built up, and right now the paint on the parts is drying as well as the baggage car (it was UP yellow, and I'm painting it to match my LGB B&O pass cars). I'll try and get a few in progress shots. 
Now the fun begins and I have to make a mail crane and mail bags. Anybody have ideas on the mail bag? I was just thinking of sewing some light cloth and tea staining it to look faded.


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## Torby (Jan 2, 2008)

Rather than a servo saver, I'd probably have used a really thin, springy and bent push rod.


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## kfrankl3 (Feb 27, 2008)

Actually the standard spring push rod was my first choice, but it didn't work consistently because it kept binding (which was a design flaw on my part). But I found the drive savers things for about 1.50 each so I bought two (one for each arm on each side), which works like a charm.


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