Kadee couplers

[Wummyock]

Hello was wondering if anyone could tell me what the minimum radius would be for the Kadee No5,17,18,19 and 20?Will the 5 and 17 travel through small radius Peco points without buffer locking?

[Oldddudders]

Hello was wondering if anyone could tell me what the minimum radius would be for the Kadee No5,17,18,19 and 20?Will the 5 and 17 travel through small radius Peco points without buffer locking?

I'm afraid that the coupling itself isn't the sole arbiter of buffer-locking. There are things within the kinematic envelope called centre throw and end throw, which are the names for the effects of a vehicle's overhang beyond the standard loading gauge on curves. Thus a 4-wheel wagon with a 10' wheelbase may have more or less end-throw than bogie bolster. Furthermore, not all NEM vehicle mountings are identical, with some e.g. certain RTR coach bodies having a designed-in side-displacement on curves, thus reducing the effect of the end-throw. As far as Kadee #5s are concerned, the individual installation varies in how far the coupling is ahead of the bufferbeam. The further forward it is placed, the more dramatic the angle to the next vehicle on curves, but the less chance of buffer locking. I recommend you buy an assortment of Kadees - say a packet of each of your named models - and see what works. I have not found a use for #17s, and #20s are not often needed.

[HLT 0109]

I have not found a use for #17s, and #20s are not often needed.

20s are definitely needed for backing-up Bachmann Mk1 coaches if using Hornby standard points.

[Butler Henderson]

Have to my own surprise found a need for 17s (usually arsing from thinking that 19 sticks out too much only to find its an 18) on some UK stock where the NEM mount is not particularly recessed and the 17 despite its shortness puts the back of the coupler neatly just in front of the plane of the buffers.

[Suzie]

I cannot see a No17 working with set track. I have bought some but never found anything with buffers that can use them when going round corners. I find that I mostly use No18 and No19 with 2' minimum radius.

 

I tend not to use No5 very often either, much better to use the longer ones (No46 for example) and set them further back to give closer coupling - if space is tight I tend to use a No16 - the draught box of the shorter 4x series tends to show when mounted in the appropriate place.

 

In my experience start with No18, No19 (and No20 for some locos) for NEM pockets (at the correct height!) and a No46 and No16 for the rest. This will probably be OK for most installations with just the occasional need for the underset/overset and shorter ones. Bear in mind that it is hard to get close coupling with the shorter ones on stock with buffers.

 

 

[Pacific231G]

It really depends on the type of rolling stock and the relationship between the NEM box and the buffer heads. Most of my Kadee fitted stock is European four wheel wagons and my general rule of thumb is to use a coupling just long enough for the inside buffing face of the knuckle to be level or slightly proud of a line between the buffer heads. This seems to avoid buffer locking on S curves and points down to about 2foot radius while giving reasonably close coupling. Some stock will take 17s especially those with retrofitted NEM boxes but I do seem to use more 18s than anything else (and I've just run out of them) Some locos have needed 19s but I don't think I've ever needed a 20.

It might be worth building a very simple test track with a small radius crossover based on the shortest points you intend to use and enough plain track beyond the two toes for a couple of your longest vehicles. I assume you've got a Kadee height gauge and it's also worth having one of their special pairs of pliers for adjusting coupling pins. I do find that the height of NEM boxes varies and they tend to be too low so I often end up inserting very thin card or paper to shim up the couplers whcih is usually a right fiddly job. If only we'd had the sort of standards the NMRA have got all the manufacturers of US outline stock to accept operation would be a lot more reliable.

[autocoach]

Don't try close coupling unless you use sprung buffers with Kadee or any other couplings. I have used #19 a lot on Hornby coaches. #46 variations with rolling stock that needs a full coupler setup. But I don't have any set track radius turnouts. If you model BR period, you might look at the Bachmann packs of sprung buffers. Reasonably priced and they seem to work well as long as you don't get glue on the shank.

[brossard]

I think I must have installed hundreds of Kadees over time. I see a lot of technical replies. For me its a balance of minimum distance between vehicles and buffer lock. I don't use Set Track. The best thing is to use empirical determinism for your couplings - if it works its good. My rule of thumb: #20 for the Bachmann Mk 1 coach or similar and #18 for wagons. Coupling height might be all over the place but there's another thread about that.

 

If the wagon doesn't have a NEM pocket then a #5 will work mounted just under the buffer beam (you may need to shim 0.020 - 0.030" to get the height). Extension will be trial and arror but once you've done one, the rest should be straightforward.

 

John

[BR60103]

There is no one answer, which is why Kadee make so many variations.

I just used a pair of 32 on an old Hornby van when I had to saw off the large integral coupling lump below the buffer beam. The 32 with inverted draft gear box matched the floor height and the box just barely stock out.

I had to substitute longer couplings than I wanted to use when my coaches overran the tender buffers on a 36" radius curve on a down grade.

I bought 19s for my Stove R but now think 18 would be better. But 20 might be necessary for first or second radius.

[Wummyock]

Thanks a lot everyone, much appreciated.