GE 25 Tonner build

[Chris333]

I bet that new motor was an upgrade besides making room. It is very smooth and slow!

[Jim Starbuck]

I bet that new motor was an upgrade besides making room. It is very smooth and slow!

Absolutely!
The Tramfabriek motors play extremely well with ESU decoders. With the gearing this little bugger will slow to a crawl and the TCS keep alive makes it rock solid through switches.

[tehachapifan]

Absolutely!
The Tramfabriek motors play extremely well with ESU decoders. With the gearing this little bugger will slow to a crawl and the TCS keep alive makes it rock solid through switches.

I'm assuming the Tramfabriek motors are basically the same as the Bachmann coreless motors like we used in the SW9/1200, right? If so, then yes, they are magnificently smooth motors and I really hope that more N scale loco manufacturers consider moving to them, as they also make more room available for sound decoders, etc.

[Jim Starbuck]

I believe the 7x16mm double shaft motor from Tramfabriek is the same as the Bachmann.
The 6x15mm from the same source is a single end shaft which is what I used in the 25 tonner and the American crane.
These slim, smooth and powerful motors have been an absolute game changer for building these small locomotives.

Jim

[peteski]

Bachmann motors, while coreless, they are really low-end motors with only 3-segment commutator.  I took one apart, so I know.  Kato coreless motors have 5-segment commutator, and some other coreless motors I have examined have 7-segment commutators. Those are really smooth with lots of torque. Think of the number of segments as number of poles in a standard open frame motor. I have no knowledge of the Tramfabriek motors.

[bbunge]

Thank you for sharing.  Amazing work.  Excellent ideas!

Bob

[Jim Starbuck]

Bachmann motors, while coreless, they are really low-end motors with only 3-segment commutator.  I took one apart, so I know.  Kato coreless motors have 5-segment commutator, and some other coreless motors I have examined have 7-segment commutators. Those are really smooth with lots of torque. Think of the number of segments as number of poles in a standard open frame motor. I have no knowledge of the Tramfabriek motors.

@peteski,
Thanks for the motor information.
Is there any way to tell by the specs what’s on the inside of the motors? As in are there particular specs to be looked for other than just physical dimensions when sourcing motors?

Jim

[fcnrwy23]

Well Done!!  👍👍

Jerry G.

[peteski]

@peteski,
Thanks for the motor information.
Is there any way to tell by the specs what’s on the inside of the motors? As in are there particular specs to be looked for other than just physical dimensions when sourcing motors?

Jim

No, I have never seen any detailed specs for those low cost coreless motors.  The manufacturers probably list them (if you know the manufacturer), but sellers usually do not include them.  High-end motor manufacturers like Maxon or Faulhaber provide all their specs, but those motors are quite pricey.

There is no way I know how to tell looking at the outside of the motor.  That is why I disassemble one (they are inexpensive enough to sacrifice one).  The low-end motors will  still work, and are good for where very small motors are needed. I just wanted to mention that they might not have the torque or longevity of Maxon motors (but still plenty good for a typical model locomotive usage.  There seems to be this belief that a coreless motor automatically means superior performance and long life, but that is not the case for every coreless motor.  Low-cost coreless motors became popular when Chinese manufacturers started producing large amounts for inexpensive radio controlled  flying toys, and spread to other types of electric powered toys and models over time.  Before that, coreless motors were usually made in Germany and they were all top quality and longevity.



Here is a photo of a Kato coreless motor showing the commutator and brushes.  It has 5 segments. Will be smoother and have more torque than a 3-segment one.



This one if from Arnold S1. Similar to Bachmann coreless motors.  It has a 3-segment commutator.

[u18b]

I use the Tramfrbriek 7x16 coreless.  I place them in all of my Shays.  By its very nature, a Shay probably requires a bit more torque.   I have found these up to the task.  They barely feel warm when running continuously.   Of course, my Shays have eventually been tuned to reduce friction.

I love these motors.

[mmagliaro]

Maxon 8mm motors use 5 commutator segments.  The 10mm and larger use 7.
As for specs, Tramrabriek does show complete specs for a lot of their motors on their website.

Example:  Their 0816D18,  which is an 8mm x 16mm dual shaft, and is the higher-rpm, more powerful version that they offer.
I say more powerful because it is, not because it has a higher max RPM.  Its stall and continuous rated torque are much
higher than their 0816D lower-speed version.
The 0816D18 continuous rated torque is  5 g-cm  (gram centimeters)

A comparable Maxon 8mm x 16mm 12v motor  #118391, rated continuous torque is 7.6 g-cm (you have to convert from
mNm to g-cm because Maxon specs all their motors in mNm units).  Still, that's a whopping 50% more powerful., with a no-load speed of only 11,600 vs the Tramfabriek's 17,800.  I would argue that getting more torque and lower speed is much more
preferable.  The Tramfabriek lower-speed version (speed comparable to the Maxon) is only 3 g-cm rated torque, so the Maxon is 250% more powerfulthan that one.

That's not to say this doesn't come at a high price.  The Tramfabriek motor is about $22 USD.  The Maxon is $78, nearly a whopping 4x more expensive.  So that boost in performance is expensive indeed.  Of course, there are big unknowns like precious metals, bearing quality, lifespan, etc.   For model train use, who can say whether any of those will matter?  We're not putting these motors into a space satellite that has to contuinuously operate for 20 years, after all.

One final thought.  My impression is that getting Maxon and Faulhaber motors on eBay or other surplus sources has become a lot harder in a post-Eldon-Shirey world.  I have no idea whether his passing away and the loss of his micro-loco-motion business had an impact on this, but it does look to me like the periodically available stashes of relatively cheap surplus Maxon and Faulhaber motors has really dried up since we lost him.

[Jim Starbuck]

This is excellent information.
Thank you gentlemen.