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DCC UnCoupling

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  • Member since
    July 2007
  • From: Yorkton, Sk, Cnd
  • 441 posts
Posted by wvg_ca on Wednesday, March 7, 2018 9:36 PM

if anyone wants to try, i can probably post specs on the pager motor to get some equivalents, i just used a couple on the back of loco's, and used fixed magnets between the track for cars further back in the train, i didn't mount any on freight cars

 

  • Member since
    March 2010
  • From: Sherwood Park, Alberta, Canada
  • 252 posts
Posted by CNR378 on Monday, March 5, 2018 5:54 PM

rrinker

  I have no idea of the specifics, Dick has removed his design from the RR-CirKits page, but I recall another using muscle wires that more or less ran the wire the length of the floor of a 40 foot car (some of that was a spring to stretch it back out when current was removed)

Actually it hasn't been removed.

http://www.rr-cirkits.com/uncoupler.html

Peter

  • Member since
    February 2002
  • From: Reading, PA
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Posted by rrinker on Monday, March 5, 2018 5:37 PM

 Decoder will coost more than other stuff, since you can usually make this work by having the actuator pull on the kadee 'air hose'. Perhaps one for Sergent couplers would be even simpler - just need an electromagnet positioned so that one pole is above the location of the ball that the uncoupling tool lifts.

 I have no idea of the specifics, Dick has removed his design from the RR-CirKits page, but I recall another using muscle wires that more or less ran the wire the length of the floor of a 40 foot car (some of that was a spring to stretch it back out when current was removed)

 The MTH ones appear to use an electromagnet to release the pin and allow the knuckle to open. The biggest problem with them is that to get the knuckle to close, you have to slam into the car you want to couple to pretty hard. No thanks.

 Addressing is definitely a problem. The bigger the layout, the worse it gets, since there are only 9999 addresses to play with (actually 10239, but few systems go past 9999). Then there are conflicts with locos, and even conflicts within the car fleet - even if you use say just the last 4 digits of the car number, if the first 2 numbers are part of a class designation, even the same railroad could end up with dupilcate numbers, say 567032 the open hopper and 847032 the 50' box car. With rolling stock from multiple roads represented, the chances of a conflich are even greater. The pictogram method used by ESU is fine, so long as the resultion is high enough to see the car number and road name or reporting marks. Then you just need to be consistent and use the same F key for the A end of every car, and the same one for the B end of every car.

                              --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    July 2007
  • From: Yorkton, Sk, Cnd
  • 441 posts
Posted by wvg_ca on Monday, March 5, 2018 5:34 PM

gregc

 i'm impressed by the simplicity of the design

but isn't the decoder the dominant cost of adding this to freight car?

on a freight car, yes ... approximtely 10 dollars ...

on a loco, just 40 cents for the pager motor, one was selected that could be driven directly from an unused  function output (about 60 ma), without damage to the output or the decoder in any way ..

all modern DCC decoders should be able to drive the spare function output at that rate

  • Member since
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Monday, March 5, 2018 4:36 PM

wvg_ca
just a pager motor (10 for 4$ from ebay)  directly driven from a DCC function output, nothing more ..

i'm impressed by the simplicity of the design

but isn't the decoder the dominant cost of adding this to freight car?

greg - Philadelphia & Reading / Reading

  • Member since
    September 2003
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Posted by Overmod on Monday, March 5, 2018 4:14 PM

Randy, what was the consensus on the best arrangement and dimension of SMA for resistive-heated uncoupling, and what was the best way to apply bias force?

  • Member since
    July 2007
  • From: Yorkton, Sk, Cnd
  • 441 posts
Posted by wvg_ca on Monday, March 5, 2018 3:55 PM

how did MTH accomplish thier version ??

I -assume- that they charged more than the 40 cents each pager motor was worth ??

I have no idea how MTH did thiers, as I have never had a MTH loco in my hands, I did this quite a while back, just sat on the layout not being used much ...

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Monday, March 5, 2018 2:20 PM

This idea is very intriguing, the issue of keeping track of the addresses can be solved by using the reporting marks car number, and if you're operating at a club you could have an extra crewmember on each train to be the uncoupler.

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    May 2004
  • 7,500 posts
Posted by 7j43k on Monday, March 5, 2018 2:04 PM

I think that particular problem can be solved by using the new ESU throttle system. While the decoder can't use an address greater than 9999, the throttle apparently can.

 

Ed

  • Member since
    January 2001
  • From: SE Minnesota
  • 6,847 posts
Posted by jrbernier on Monday, March 5, 2018 11:48 AM

  Many freight car numbers are 5 or 6 digits.  DCC will only address 4 digits...

Modeling BNSF  and Milwaukee Road in SW Wisconsin

  • Member since
    July 2007
  • From: Yorkton, Sk, Cnd
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Posted by wvg_ca on Monday, March 5, 2018 10:15 AM

it was just a low cost experiment, no where's near MTH levels....

just a pager motor (10 for 4$ from ebay)  directly driven from a DCC function output, nothing more ..

piece of string for a coupler tie, that's all

as far as remembering the number on a freight car, well, why not use the road number ??  same as on a loco ??

  • Member since
    February 2002
  • From: Reading, PA
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Posted by rrinker on Monday, March 5, 2018 7:30 AM

 Having an MTH loco with this feature - it's mostly a gimmick. The loco is not where you need to uncouple most of the time, it's several cars back in the train. Long before MTH put it in HO locos, people were putting it in HO rolling stock, using either small pager motors or muscle wires. It was a long time ago Dick Bronson (from RRCirKits) showed me his setup at a train show. But putting a decoder in every freight car - and then trying to remember all the addresses - seems like a next to impossible feat.

                                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    July 2007
  • From: Yorkton, Sk, Cnd
  • 441 posts
DCC UnCoupling
Posted by wvg_ca on Monday, March 5, 2018 4:46 AM

pretty straight forward as title suggests

video at https://plus.google.com/photos/103012970276430167790/album/6106164158873113617/6333361327063101714

 

needs DCC with extra functions(s), small DC motor to actuate uncoupling, tested on HO sized loco

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