Ok. This modern critter has been seen here before. TP56 is a small but brutish critter. Videos have it pulling 20 car strings. This one is 3d print. I sat it on a low profile SD40-2 truck as the prototype. Took a N scale motor and fit it in. Problem, the Trix motor doesnt quite have the starting torque to get it moving without high volt input (DCC) I did rebuild the truck and clean off and file all the possible friction points. any idea what will fit in its place but do better in the torque department? The first pick gives a good idea of the size. It fits in the very front. a possible turn around putting it in the cab is possible
Shane
A pessimist sees a dark tunnel
An optimist sees the light at the end of the tunnel
A realist sees a frieght train
An engineer sees three idiots standing on the tracks stairing blankly in space
People seem to have good luck by replacing the magnets with niobium (sp) magnets.
That;s mainly for the bigger open frame motors, where the magnet is a big slug at the back.
What diameter fits in that calmp-like mount that holds the motor? One of the round can motors that NWSL has, or used to have, might fit.
ANd just how bad is it? Does it leap into action once you get above a certain speed step? If it runs slowly, but needs a high throttle to get moving, you might just need to adjust the start voltage, and maybe use a decoder with better BEMF, or tuning the BEMF to suit this motor may help - it can make a huge difference.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Randy raises good points. I have a small engine with a similar problem. In addition to the kick start voltage, I adjusted the maximum voltage to prevent it from reaching a very high speed. So the engine starts relatively fast, but maxes out quickly on the throttle, preventing it from reaching slot car speed. But it's not a switcher in my case - more of a shelf queen that can work on track - so your expectations may be higher.
Exploring a motor change is still a worthy exercise, especially if the CV adjustments are not satisfactory. In my case, the space for a motor is tiny (it's Hon3), and the shaft is very long. So replacing the motor is not obvious and not worth the effort. In your case, you could measure the space and see what's available at NWSL and Ebay (mabuchi, cannon, etc.). I find small 12V motors hard to find.
Nice looking switcher by the way!
Simon
You might try the Minebea SE15HOSLTP motor. I haven’t tried it myself but the specs look promising. I went to the Minebea website looking for the stall current and nothing comes up. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
It appears to me that this is a poster child for more gear reduction. If 'cost is no object' I'd look into seeing if a gearhead motor, perhaps installed as the OP indicated in the cab or hood 'facing the other way' would provide the desired speed reduction and torque increase; you would then be able to tune the speed steps and back EMF detection to optimize the starting and slow-speed range much better.
Are there approaches to installing a planetary or other reduction-gear approach in such a chassis? I am reminded of the early use of Delrin chains in conjunction with a coreless motor in achieving very smooth slow-speed operation on DC in the very early '70s, before fancy PWM was cost-effective.
It does take a high kick at a jack rabit start, but I can get it quite slow. But as soon as it stops, needs that jack rabbit start. The clamp mount is holding the part of the motor where the commutator is. I have no issue rebuilding the mounts as need be since I built it in the first place.
there is little space for a regear. Unless somebody had a reduction gear assembly built into an Athearn low profile 3 axle truck. I used that truck for ease of building. But if I absolutely need too, I will completely build a truck assembly.
The decoder running this is an NCE one for tight space. sits in the cab area.
The regearing reminded. me that Faller has a motor and reduction gear tower, wonder if that fits.
This being able to be turned down very slow, but requiring very high starting torque followed by breakaway tells me there is a problem with the drive, not the motor. This sounds like a flexible coupling is misaligned or binding, and starting torque distorts or jams it, but even slow continuous rotation doesn't. Perhaps turning the motor shaft by hand with the weighted chassis on the track will indicate what is binding and then releasing.