Un coupling

Something that has been rattling round my brain for several years now has been a method of remote uncoupling with DCC. My neurons have looked at and discarded several ideas, and asked 'where is the beer?' Last weekend something gelled when I was thinking about something else, and so I wandered out to the Man-sion to knock up a prototype.

My previous tests had revolved around electro magnets behind the buffer beams. However there was always the problem of fitting a large electromagent....well....anywhere really. This then sort of evolved to several neurons mooting an actuating rod through an electromagnet that fortunately died a death in a second bottle of red wine late one night.

The latest idea has turned back to something that my inner geek has always looked at and thought 'that would just be cool'. Memory wire has been mentioned before here but more in the 'cool toy in search of an application'. Here is one that I think might fit. Memory wire shrinks about 3.5% as it is heated ie when a current is applied across it due to some weird chemistry stuff which I should be able to explain but can't as I was asleep that morning in class (it was warmer than the flat).

So, not actually having any memory wire I made do with the bits I had. The main hurdle was to design a linkage of some sort to modify the motion for the microtrains coupler. 2 Minutes with a bit of plastic and some copper wire and the first prototype was born.
(the wagon is being used as it was available, not because I'm planning to put them in wagons...)


This was designed to pull the coupler sideways while keeping the linear motion of the wire. The required pull distance is only 2mm so a length of memory wire of about 60mm should do the job.

'Must buy a tripod'

The prototype seems to work, so the next step is to actually build a real one.

One problem that has occurred to me is that when going round corners the couple has to move to the other side which should be limited by the solid wire linkage. There might have to be a spring in it somewhere to allow some extra movement.