Uncoupler

Timothy Cann
 

It has been my goal over the past six months or so to build an uncoupler that could be used manually (like the prototype), or automated under DCC control. My hope has been to have the uncoupler look and operate as close to the prototype as possible. This project has taken me down numerous paths looking for the right hardware that could be driven by a standard DCC decoder using one LED driver for each end of the car.
And yes, I’m aware that this is probably not a practical thing to do, especially because of the cost, and those of you who are firmly of this mind can remind me as often as you like. Managing the DCC addresses (two per car) is also going to be a challenge during operating sessions.

Kadee couplers were my choice at the beginning, but as soon as Sergent Engineering couplers came to my attention, I’ve never looked back. Their magnetic uncoupling design seemed a natural for my project. There are uncoupler designs on the Internet that use Kadee, I built several of them, but for my taste they simply did not look or operate like the prototype. If any of you are interested in the steps taken to come to this conclusion, I’d be glad to summarize the steps.

I’ve now successfully built a prototype using EN87 couplers, built after many hours of SolidWorks 3D design work. My next step is to finish at least two cars and an engine, including painting and weathering, so a video can be produced showing the operation. Some parts are purchased, some are 3D printed (my Anycubic Photon, a liquid resin printer, meets the detail and size required).
There is no motivation for me to get any financial gain; my design will be posted to this website when I’ve completed the documentation, including the 3D printed parts’ printer files. Final documentation will include the source of each of the purchased parts along with the cost. It looks like the cost per car to add the DCC and mechanical parts for two couplers is about $100, but that number is by no means final. I’m using all brass rolling stock, which puts the cost per car including the car itself, couplers, electrical 4-wheel trucks, mechanical parts and DCC decoder at about $300 minimum.

To my delight this design can be used without DCC, simply move one of the handles to lower and raise the magnet, just like the prototype. The only thing that is not prototypical is the uncouple operation is backwards: lever down = uncouple, while the prototype is lever up = uncouple.

Included with this post is a SolidWorks animation (MP4 zipped) to show how this works.  It's posted in the Files section.

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