Have you ever wondered which Kadee coupler was the "correct" one for your
application? Are you confused by the many Kadee coupler model numbers?
Well, let me try to help sort this out a little.
Let me start by saying that on my HO rolling stock, I have rarely used
anything but a Kadee #5 coupler. This is mainly because of philosophy
-- I prefer to file, shim, cut, drill, or tap to make a #5 work. However,
I also have worked with many of the "other" types of Kadee couplers.
It is with this background that I am going to try to sort out some of the
mystery behind the various types of Kadee couplers.
I have grouped Kadee couplers into four different categories depending on
their shank and draft gear style. It is difficult to describe each without
pictures, but I will try.
- This style is easiest to describe because most everyone knows what a #5 coupler looks like. The shank has a round hole and flat sides. The centering spring presses against the flat sides. The draft gear is rectangular. Kadee calls this shank style "Type B".
- This shank has a keyhole style hole in it. The front (slot) of the hole accepts a coil centering spring. The rear of the shank is round as opposed to flat like the #5. The rear of the assembled draft gear is also round to minimize clearance problems. Kadee calls this shank style "Type C".
- This shank has no hole (for a screw to pass through). Instead there is a slot (a rectangular hole) in the shank which accepts a coil centering spring. The end of the shank is rectangular. Kadee has only two coupler styles of this type. The assembled draft gear for both are "identical" to a #5 except without the center hole. Kadee calls this shank style "Type A".
- These couplers are designed to have the shortest distance between the post hole and rear of draft gear. While the shank is like that of a #5, the draft gear is redesigned for very close fitting applications. Because the shank is like that of the #5, Kadee refers to these as "Type B".
Within each of these categories, there are a various shaft lengths and
vertical knuckle offsets. Let me start out by listing the Kadee model
numbers in a table. This table will do two things. First it will group
the coupler types into the groups described above. Second, it will list
the couplers in order of their shaft length (distance from center of post
to end of shank). Even though some may be reduced, lengths will be shown
as a fraction with a denominator of 64. This makes comparisons somewhat
#5 Round Rectangular Short | Length Offset?
-- ----- ----------- ----- | ------ -------
23 33 | 16/64 no
24 7 34 | 16/64 yes
38 | 17/64 no
3,5,9,28 4,15 | 18/64 no
22 32 | 18/64 yes*
27 37 | 18/64 yes
8 | 20/64 no
21 31 | 25/64 yes
26 36 | 25/64 no
29 39 | 25/64 yes*
6,16 | 26/64 no
- "Offset" means the shank is attached to the bottom of the coupler like this: ___ as opposed to this: ---
- #3 is simply an assembled #5
- #4 has a metal draft gear box with no hole in center
- #9 is a #5 with a smaller hole in draft gear box
- #15 is an insulated #4
- #16 is a #6 with #7 (short) draft gear
- #17(short), 18(medium), 19(long), 20(x-long) are for Roco applications
- #21,22,26,27,28 have additional hardware for Talgo applications
- #22,32 has an inverse offset where the shank is attached to the top of the knuckle
From this table one can make several generalizations:
- a coupler number ending in 7 or a 1 means that it has an offset knuckle
- a coupler number ending in 2 means that it has an inverse offset knuckle
- a coupler number ending in 6 means that it is long
- a coupler number beginning in 3 means that has short draft gear
- a coupler number beginning in 2 means that has talgo parts
For more detailed information on such things as offset distances, see the
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