Coupler droop, height and centering


Malcolm H. Houck
 

Does anyone have experience with the scale couplers and were any changes
required to insure reliable operation?

There has been considerable concern about whether or not "scale" couplers
will "gather" properly and couple with other sizes, or if they will or will
not
couple properly on curved track.

If this's a problem it is, in my opinion more related to the side play
between
wheelsets and truck frames; -- a topic much discussed with JP Barger. An
answer is to replace the "one size fits all" wheelsets with ReBoxx
wheelsets
that are (can be) more carefully matched to the varying distances across
truck frames between journals. This can easily be done since ReBoxx
are made in a variety of lengths and, with careful measurement taking into
account the manufactured specification of lengths, can be matched to
a nearest 0.001".

With replacement wheelsets all cars center on the track and scale coupler
matched are not a problem. . . at all! In addition, since the elimination
of
truck side plat also eliminates vertical play, couplers will be (should be)
all
at a proper height above the rails. In replacing all OEM and other
replacement
wheelsets with ReBoxx sets I have ben able to discard nearly all shim
washers
previously needed to obtain correct coupler height.

An additional benefit is that with a correctly fitted ReBoxx wheelset a
truck
rolls extremely well. The finer tread width seems to have no problems with
well done track, besides.

Mal Houck


Tony Thompson
 

Mal Houck wrote:
Does anyone have experience with the scale couplers and were any changes required to insure reliable operation?

There has been considerable concern about whether or not "scale" couplers will "gather" properly and couple with other sizes, or if they will or will not couple properly on curved track.
Obviously it depends on the sharpness of the curves. I assume you are comparing #5 with #58 couplers, and yes of course, the smaller heads have less gathering range. And you know what? The prototype is the same. Prototype drawbars often have to be kicked or otherwise nudged to couple on curved track, and on a strong curvature, it may not be possible to couple conventional freight cars. (That's why traction lines had special couplers.) Some modelers do complain about the small-head couplers, in this regard, but to me it is, if anything, a step toward realism, and away from the toy-train " couple anything, anywhere" routine we were used to.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, tony@signaturepress.com
Publishers of books on railroad history


William Keene <wakeene@...>
 

Hello Group,

I install and operate using Sergent scale couplers and have found them to be quite reliable. And I second what Tony Thompson has commented that nudging coupler drawbars is a more realistic operation. I have also noticed that switching operations are done at slower speeds which is also more prototypically correct.

Cheers,
Bill Keene
Irvine, CA

On Jul 13, 2013, at 10:48 AM, Tony Thompson <tony@signaturepress.com> wrote:

Mal Houck wrote:
Does anyone have experience with the scale couplers and were any changes required to insure reliable operation?

There has been considerable concern about whether or not "scale" couplers will "gather" properly and couple with other sizes, or if they will or will not couple properly on curved track.
Obviously it depends on the sharpness of the curves. I assume you are comparing #5 with #58 couplers, and yes of course, the smaller heads have less gathering range. And you know what? The prototype is the same. Prototype drawbars often have to be kicked or otherwise nudged to couple on curved track, and on a strong curvature, it may not be possible to couple conventional freight cars. (That's why traction lines had special couplers.) Some modelers do complain about the small-head couplers, in this regard, but to me it is, if anything, a step toward realism, and away from the toy-train " couple anything, anywhere" routine we were used to.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, tony@signaturepress.com
Publishers of books on railroad history