I’m working on replacing some of my couplers on my cars.
This package says Reverse draft angle, what the heck is that?
Thanks
Chris
Chris, A draft angle is usually associated with castings. You need to leave a bit of “draft” to allow the cured or solidified casting to exit the mold.
If you mead draft gear, then reversing it will yield a different coupler height above the rail. This is because the drafr=t gear box is not symetrical from top to bottom. The Kaydee instructions that come with their No, 37 couplers cover this in better detail.
BB
While it may be true that it was related to the way the part comes out of the mold, Micro-Trains seemed to imply it was an improvement in the pulling power (“draft”) of the coupler as well. MT “reverse draft angle” couplers theoretically stay coupled better in longer trains, according to the manufacturer.
I happened to be doing some research in an old MR (Dec '96) and stumbled upon one of the earlier ads for the RDA coupler that at least indicates what MT was saying about them at the time.

In actual use, I don’t notice any difference between cars with RDA couplers and those with older “non-RDA” couplers, but my small switching layouts don’t present much of a test of coupler pulling performance anyway. And there is no difference in coupler height between RDA and non-RDA of the same type.
Regards,
Byron