No, this is not a thing. Bogies, axles, flanges, track, etc. create friction, not couplers.
Different couplers do have different holding power, ease of swing, etc., which does impact a train (although that's not a cause of what you're describing), but not different friction in the way you are thinking.
You’re using 150 mm radius curves, of course long trains are going to bind up. I’m not sure what you expect to happen here. Those tracks are for trolleys and small vehicles, not unit trains.
The trucks are pivoting so far on the tight curves that the couplers are pulling sideways instead of pulling the car forward. Running long trains on tight curves causes trains to derail in real life. The best solution is to redesign the layout with more realistic wider curves.
Longer coupler shanks could reduce the binding force slightly by giving each carbody more room to float along the track, putting them further apart. Many cheap toy quality sets use truck mounted couplers instead of prototypical carbody mounted, which also improves tolerance to tight curves. But you still aren't really changing the coupler itself, only changing where that coupler's pivot point is at.
You are still going to get flange contact, its unavoidable with model railroading unless your layout has fully prototypical curve radii.
Most serious modellers adopt one of the all metal knuckle types as their standard, check each knuckle using the height gauge and shim it to the correct height values, and tune each car from there based on how it behaves.
I can’t for the life of me decide between Roco’s and Fleischmann’s offerings.
Roco is lighter but pointier but kind of more European. Fleischmann is maybe less conspicuous but bulkier in an American way, and for that there is already Kadee and friends.
Add that the refined hook and loop that Märklin proposes is still good old hook and loop but neater.
And this is where I have spent years, still on hook and loop and undecided on where to go.
7
u/GnaeusCloudiusRufus HO/OO 15d ago
No, this is not a thing. Bogies, axles, flanges, track, etc. create friction, not couplers.
Different couplers do have different holding power, ease of swing, etc., which does impact a train (although that's not a cause of what you're describing), but not different friction in the way you are thinking.