Lindsay G wrote:Electromagnetic uncouplers seem to introduce more and more considerations. Might non-electro uncouplers simplify matters? There's a couple of neodymium magnets epoxied to the upper end of the brass piston in the image below. There's then no worries about keeping your finger on the button for too long. They're also a lot cheaper, and by leaving a crank elsewhere on the truncated servo arm several more magnet sleeves could be operated from the same servo, reducing costs even further and providing other benefits.
Of course we might then introduce other considerations and get back to such other issues as twitching servos again. It's still to be tested in anger, but seems to work fine on the work bench.
I've used something very similar before. It works fine for AJ's and other couplers requiring vertical pull.
BUT, there is a gotcha, which affects me (and perhaps others..). If you fit couplings on locos with my DCC controlled mechanism, it is very sensitive to the pull from magnets in the general vacinity. So, for my locos, permenant magnets which retract need to move large distances to remove the impact of the field, or be rotated, or otherwise magnetically shielded when not in use.
- Nigel