Kadee alternative for scale-like couplers

Intriguing idea. Does the material have enough strength to handle the stress or can you get them 3D printed in metal?

@AGHRMatt posted:

Intriguing idea. Does the material have enough strength to handle the stress or can you get them 3D printed in metal?

Great question... I’m looking into both options. I can tell you from my initial investigation that 3D printed metal would be my preference BUT is going to be pretty expensive; like >$30 per car... they can’t be on a sprue for metal printing.

oh well, back to the drawing board.

@CentralFan1976 posted:

I'm thinking of a stop-gap alternative until I can get the 3D design for the Kadee mounts for the Amfleets finished... One is a down & dirty replacement for the stock "claw" couplers.  this would keep the truck-mounted design with a scale-ish coupler head and is non-functional.   It would be considerably shorter than the stock couplers, and the pulling faces would be at the ends of the diaphragms, so they would touch.  At this time, functionality on passenger cars isn't a high priority IMHO.

With that said, I'd like your opinions and thoughts...

Thanks,

- Mario

Accurail in HO scale sends dummy knuckle couplers with every freight car they sell. I use to run a 25 car coal train with these couplers. Never had to worry about cars uncoupling at all, next time you visit a hobby shop look for white or yellow boxes. Coal cars was a molded one piece, other cars was a molded two piece.

If they're temporary, just print them out of plastic. the MTH cars are not that heavy, and the print will be the weakest in the Z direction, so just print them flat on the mat. I suspect they'll be just fine as they're thick enough to have a decent number of layers. Larger layer height is stronger than smaller ones, and the fidelity of these doesnt matter... the layer lines arent going to matter. Try a .6 nozzle and let em rip. I doubt they'll snap. If anything, they might flex or stretch a little.

If you print them yourself and they break, what are you out? $.50 worth of filament?  Absolutely worth a shot to see if it works.

@CentralFan1976 posted:

Great question... I’m looking into both options. I can tell you from my initial investigation that 3D printed metal would be my preference BUT is going to be pretty expensive; like >$30 per car... they can’t be on a sprue for metal printing.

oh well, back to the drawing board.

Maybe not. You could make up a 3D printed plastic set on a sprue, then do a "lost plastic" casting in brass.

@AGHRMatt posted:

Maybe not. You could make up a 3D printed plastic set on a sprue, then do a "lost plastic" casting in brass.

Shapeways can do that for you. I have done it. The minimum charge is $12.50 (as of a few months ago). You can print 2 identical items, but the size limit is real small. Its meant for things like cufflinks. You can sprue these together and see if it fits in their bounds.

Mario says that these are temporary until he can produce a final design.  Here's an example of dummy couplers that my nephew printed using a filament printer.  I haven't experienced any breakage yet, but there is room to beef them up if we do have a problem.

Jan

Thank you all!

Here are some pictures taken at Dr. Jacks utilizing Kadee couplers for O Gauge passenger cars. They work great. Great thread, good subject. Happy Railroading