Well, the time has come to add uncoupling ramps. I have had multiple layouts and this is the first time I have actually had an uncoupling ramp since my earliest days with NMRA couplers! The first thing we have to do is to cut a slot in the track structure to allow placement of the ramp. I use a mix of Weaver and Kadee couplers which open under the influence of a magnet that is polarized towards the each of the running rails. There are now super magnets available on eBay and even at your local hardware store that provide the ability to achieve that type of polarization.
I used a Dremel motor tool to cut the ties near a turnout where I might drop a cut of cars. I then place a screw for each magnet to act as a base that I can level to a preset depth. I make the screw head 1/4 inch below railtop. This height was determined by Ed Rappe when he started using this approach and it works for me.
It takes some planning to place the ramps as you have to think about the typical moves you will make to switch cars on the layout. It is amazing how many ramps you will want to handle a small town! A
These are the super magnets. They are polarized to the top and bottom of each 8MM cylinder. The are N50 in strength and cost about $0.10 each when you buy 100 at a time off eBay. Hard to believe but they come all the way from China at that price! Each ramp will use 8 magnets. Thus, they get absorbed pretty quick if you are dealing with a number of ramps.
Now the magnets are in place. The top of the magnet has been colored with a Sharpie to show North. All the magnets on one side of the track are north side up, the other side is south side up. The ramps are initially held in place by the magnetic attraction to the screw heads. Then they are ballasted over and the glue holding down the ballast also holds down the ramps. The ramp disappears into the scenery. I have to place an indicator of some sort so the engineer and the conductors know where they are located.
As we bring a car up to the ramp, the coupler is its normal, closed position. The curved wire is sort of slightly down one side of the of the center line of the car. This curved wire is what opens the face of the coupler when the wire is attracted to the side.
Here the uncoupling ramp has opened the coupler by attracting the wire to the south rail.. The wire does not touch the magnets but their force is sufficient to open the couple face. If it had been connected to another car, the engine could reverse and leave one car on the ramp. As I worked, we installed about 13 ramps in Weigh Scales. That consumed 114 magnets. Thus, they go fast.
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