Coasting drive?

[Anonymous]

Hi all,

I was at a friends house one day and he had a brass model that had something called "Coasting Drive" as I understand it, coasting drive allows a locomotive's driving wheels to roll freely without any power on the tracks. Really cool!

But, I'm wondering, how does this "Coasting Drive" actually work? is it part
of a special motor, gearbox etc?

And last, but not least, is it something one can add to other models relatively easily?

Thanks,
Alvie.

[AltonFan]

There was an article about this in Model Railroader in the 1980s.

I got the impression from the article that some of the drive parts needed are rather unusual items, a coreless motor is required, and "high-tech lubricants" are needed. (At least as of the 1980s.)

[cacole]

Actually, you can get the same effect today with momentum set high in a DCC decoder. Instead of actually coasting, though, the decoder stops the locomotive according to the amoung of momentum programmed, ranging from instantaneous stopping, up to around 30 seconds. I can understand the mechanical theory behind a coasting drive in one direction, but how would you back the locomotive?

[Anonymous]

QUOTE: Originally posted by AlvieCO

Hi all,

I was at a friends house one day and he had a brass model that had something called "Coasting Drive" as I understand it, coasting drive allows a locomotive's driving wheels to roll freely without any power on the tracks. Really cool!

But, I'm wondering, how does this "Coasting Drive" actually work? is it part
of a special motor, gearbox etc?

And last, but not least, is it something one can add to other models relatively easily?

Thanks,
Alvie.

If you are talking about the Key engines with the coasting drive, I can tell you some things about those. I have several with the coasting drive, but it is a mechanical design in the gear box that allows the worm to move away from the gear. I can pu***he engine back and forth on the track without power and it will disengage the worm and allow you to move it like a non-powered model. When you operate on a layout, you have to be advised that if you stop and the worm disengages, the whole train will roll downhill.

I have not idea if you can purchase it from Key, but you could certainly ask them if they sell the gear box. I believe that is the only one they use since they started with the coasting drive back in 1986 or so. I like it for the home use, but I do not use them on a club layout because of the possible runaway situation. If you stop and keep power on the unit, they usually do not disengage, but you can have a problem on a downhill run holding back the train if it does disengage.

The main advantage is they tend to run great!