I have read somewhere that if you double head Athearn diesels in a lashup with Kaydee couplers it will create a short. Is this true and how does one avoid that and use KD couplers
Thanks
Use the plastic shank 30 series couplers. I’m not sure off hand, but believe the #38 is the plastic version of the #5 (medium centerset).
What I ended up doing on all my Athearns is to body mount the Kadee #5 in it’s own box. This also allows you to detail the pilot add plows etc and shell removal is done w/o bothering any coupler or pilot detail. I never liked the coupler mounted on those frames lugs anyway.
I have not looked closely at the wiring on the RTR Athearns, so I don’t know if what you have heard is true. As a precaution, I would recommend using the Kadees with a plastic shank. You can get them in short, regular, and long lengths; also, you can get them in underset and overset in addition to the normal heighth. Just go to your local hobbystore or look in the Walthers catalog and figure out which version you need. I install these plastic shanked Kadees on all of my locomotives as a precaution against shorting problems.
BNSF76
I have two pairs of Athearn BB locos that I run in lash-ups of two each. The trucks in the lead loco are wired directly to the trucks it the trailing loco so they pick up power as a sixteen wheel unit. To avoid the shorting problem through the couplers I put in McHenry couplers on which the coupling jaw is glued closed so there’s no possibility of the couplers opening.
Athearn’s, (and P2K and many other locomotives) use the chassis to conduct electricity from the wheels to the motor. Metal couplers, that contact the chassis, will be electrically “hot”. When two such locomotives are coupled together you have a 50-50 chance of a short. Half the time the chassis of one locomotive is common to the north rail and the other locomotive will be common with the south rail, and when coupled up with conductive couplers, you get a short. Turn one locomotive around, head for tail, and the short will go away as now both chassis will be common to the same rail.
As a general rule, I always use non conducting couplers on locomotives. Either the Kadee 30 series, or careful mounting of a metal Kadee in a plastic Kadee coupler box using a nylon 2-56 screw to secure the coupler box to the metal chassis.
Older BB Athearns use the chassis as a ground. If you run them nose to tail there is no problem. The problem occurs when you run them nose to nose or tail to tail and the metal couplers complete a short circuit. Plastic couplers is the answer here. The new “DCC Ready” units have the motors insulated from the chassis, so there’s no problem with shorts there. My [2c]
Use KD 38s that will solve the problem on the BB/BB-RTR …Many of the newer Athearn RTRs has a plastic coupler box.
ATHEARN ENGINES have ‘hot’ shassis’ - Chassis’ are connected to motor and engineers side wheels. Metal screw electirically connects metal couplers to a metal chassis,
ATHEARN BB: best sulution is to use Kadee 30 series couplers. Exception: for DCC equipped engines. Kadee makes plastic 2-56 screws but I find the bind and break off too easily turning in the hole. Discard.
GENESIS ‘F’ units: #28 A and #33 between units. #26 and #38’s for tight curves.
Blue box freight cars benefit from ‘cutting off’ the molded-on coupler box and replacing with Kadee #5 or 40 series coupler and coupler box. Replace any old metal trucks, too. They’ll roll better, plus wheel pickup won’t reach chassis due to newer plastic sideframes.
Thanks you all for your time to respond.
All that is needed is to mount a #5 in the plastic draft gear box, you can even use a metal screw as it can’t touch the coupler because of the plastic box.
Hmmm…never thought about Athearn locos having shorts…but then again I use plastic McHenrys…
Phil
I had been told McHenerys were not reliable. Is this not true. On small layouts where one is not pulling more than fifteen or so cars is it necessary to change over to KDs or will the McHenerys and Accumates work ok. Just coming into HO from Lionel so I have a lot of questions. Thanks
Personally, I don’t care for plastic couplers. I’ve had too many of them break the whole head off, or break the knuckle, or have the spring break off, etc. I might leave them on a freight car if they were factory installed, but for a locomotive, I’d definitely change them out for metal (Kadee #5 or 40-series).
As for your locomotive, you can use a #5 in it IF you use the plastic draft gear and mount it to the chassis with a screw. The plastic housing will keep any part of the metal coupler shank from touching the chassis. Problem solved! [:)]
I thought they had pants…
I run #28 synthetic shank Kadees in all of my engines w/o trouble. I’ve had more problems with McHenry and Accumates than I care to recall. In fact I install #5s in all of my rolling stock upon purchase. Don’t forget to check the coupler height.
Accurail makes black plastic ‘dummy’ couplers that are inexpensive and will couple with a Kadee couper, although of course they won’t automatically couple with each other. I use them on some locomotives, especially on diesels that will run back-to-back to avoid accidental uncouplings, on on “miniquad” sets of ore cars, with the end cars having Kadees on one end.
I use Kadee 5, 8, and 40 series couplers on my equipment. Just have to file the mounting pad to get the coupler the correct height using teh Kadee gauge. Once everything is right I cement the coupler box to the frame and then add a 2x56 screw. The box insulates the coupler from the frame eliminating the potential for a short through the couplers.
I don’t advise using any other coupler except Kadee. The imposters are junk.
Que?
I put Kadee’s on all my loco’s Athearn and otherwise and use them in multiple unit lash-ups, facing forward and backwards, all the time. I have yet to have a shorting problem. The newer RTR models have a pretty thick coat of paint on the frame which insulates it pretty well.
Tilden
Kadee pioneered the knuckle coupler and still makes very good ones. The Kadee patents finally expired in the 1990’s and a number of clone couplers came onto the market. The weak spot in many clones is the use of a molded on plastic finger to serve as a knuckle closing spring. The plastic finger is prone to breaking off, or taking a set, after which the knuckle fails to close and stay closed. Later clone couplers adopted the bronze knuckle coil spring idea from Kadee and are much more reliable. All rolling stock now comes from the factory with clone knuckle couplers 'cause the clones can be molded by the company making the car, which is a lot cheaper than buying them from Kadee.
I run such cars with the factory clone coupler until the coupler breaks, at which point I replace them with Kadee’s. As a hobbyist, buying packs of couplers at our friendly local hobby shop, the Kadee’s cost no more than clones, so why not buy the best?
All knuckle couplers have to be at the same height about the railhead. One coupler low, one coupler high will cause random uncoupling. You want to buy or make a coupler height gauge and test all your rolling stock. The usual fix for low flying couplers is a number 6 flat washer slipped under the trucks to raise the entire car. If the “gladhands” (the magnetic uncoupling arm) catch on turnouts and crossovers, it’s a good bet the coupler itself is low. I always check coupler height before bending the gladhands up.