Hook on bottom of coupler

[SantaFeDave]

the little hook on the bottom of the coupler on a few of my cars keep hooking the rails and derailing. Is this hook needed or decoration?

[jbrock27]

It is known as a "trip pin" and is really only important if you plan to magnetically uncouple your rolling stock.  It being too low would prompt me to measure the height of the coupler using a Kadee Coupler Height Gauge, the plastic version, # 206 (the other version is metal and you put it on the tracks.  The plastic version keeps a short from occurring if you leave the power on the tracks).
An option is to trim the pin with a pair of side cutters or what I call "dykes".
A better option, I think, is to get a pair of Kadee Trip Pin Pliers, specially made to turn them up or down.

[electrical whiz kid]

Dave and Jim;
Why not just get a
kadee gauge?  Stuff like couplers, wheelsets, etc; have to conform to my standards; this way, there are no questions about this car, or that engine...etc.  They are bot what I call cheap, but worth it.  They are widely available; but for my mind, I go right through Kadee.  

Rich
SGT C.
 

[jbrock27]

Sarge, it is unclear to me why you are giving me that advice.  Hello, I think you missed some key elements in my post

[SantaFeDave]

Thanks, I'll do that.

[jbrock27]

You're welcome.  Both of those tools, as well as a "truck tuner" are all worth getting.  Unlike Sarge , though, I would shop around, bc I bet you can find better prices than directly through  Kadee.  Maybe not, but I would look around first anyway, knowing I could always get it from there if all else fails.