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A friend of mine sent me this link to Sergent Engineering. They make a very nice looking, operational, scale coupler. I think these will improve the look of my models, but don't know how well they operate or how hard to instal / use they are. Does anyone use these couplers? How do you like them? Any feed back would be appreciated.



Registered Member
Staff member
Hi CP, well I have no experience with those couplers, but I find them quite interesting. They look real, the literature seems to indicate they are more easily uncoupled than the Kadee (magnetic wand) and they seem to be closer to prototypical in operation and in looks. Wish they had some graphics like the Kadee site has, but since they don't, I'd like to hear a bit more on these also. I guess I might have to buy a couple of packages to try them out but I doubt they have made their way up here yet.
Cheers Willis


i bought the sergent engineering couplers (expensive though i bought 10 pair for 30 bucks) they look and operate great easy to install and i love how you can leave open knuckles on cars and they operate very smoothly. ill have to get off my lazy but and post some photo's here in a few days


Been Nothin' Since Frisco
Scroll down past the dynamic brake photos and look at the pilot of the model on this page for a shot of Sergent couplers:

Brian Banna does fantastic work and these couplers complement his attention to detail quite well. If you get a chance, look at the rest of his step-by-step on his SD38-2.


yeah i dont really recomend them for a larger layout with alot of yard slow to open knuckles and align the couplers....arm gets tired real quick...i suggest they be used in a small switching haveing a total of 20 cars equipped only 10 on the layout at a time.


New Member
Sergeant couplers (HO)

They are nearly scale-size and operate exactly per prototype when coupling. A magnetic wand causes the same effect as the uncoupling lever when uncoupling. This product has transformed my operations.


Active Member
do these work with under rail magnets for uncoupling?

No there is a little ball bearing in the coupler that loks the knuckle in place. The magnet wand goes over the top of the coupler and lifts the ball allowing the knuckle to open. I have tried them and they would be great for a small switching layout or contest model but not for a large layout or club or bad track.

If you want Steve I will send you a pair so you can try them out when I am done with your units.


Well-Known Member
These couplers sound nearly identical other than the iron ball to lift the uncoupling pin, as on the real thing. They are a nice looking coupler alright!

In looking at the link above it looks very similar to what I remember Ken had made.
I wonder if by chance he and Sergent ever colaberated?

My prior friend Ken Barnhart, machinest, pattern maker and investment caster showed me couplers like these he produced many years ago. They looked just like the real thing and operated about the same too.

Ken would take a piece and reduce it down in size to fit the HOn3 equipment he used to make. Quite a guy, too bad he's gone.


Active Member
mark if you dont mind, that would be great. Maybe i'll eventually convert a few. It would be nice if they were able to figure out a way to use existing kadee magnets.


They are very nice couplers I have been using them for a while now I just finished building a few drilled top sets this evening


They will couple to SCALE HEAD Kadee couplers. However, it's not a simple push together and go. You will have to slip one coupler over the other to get them to hitch since the two brands use different mechanisms to open the knuckle.


They're using a magnetic stick to activate the uncoupling process. Would it be possible to use opposite pole magnet to push the ball bearing up from underneath? And why not use a centering spring to keep the couplers aligned for automatic coupling?


The ball is not a magnet, so an opposite pole won't do you any good.

Try this. Take a magnet with two poles, and try to stick it to your refrigerator. Now, flip the magnet so that the opposite pole is against the refrigerator.

Depending on the size and shape of the magnet, it will either stick to the refrigerator like the other pole, or it won't stick at all. It won't repel itself from the refrigerator.


Greg Amer
And why not use a centering spring to keep the couplers aligned for automatic coupling?

I think Sergent is going for a more prototypical coupler. Not only is it scale size, it operates similar to real couplers. Real couplers don't self center and they only couple if at least one knuckle is open. The lack of a centering spring also makes it possible to couple on tighter curves.


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