Motor Ideas

[Nathan Jahreis]

This is just for fun. Think of some sort of motor that has allot of torque but is smooth and slow, that can be applied into an HO gauge. Get your Imaginative juices flowing ! Go crazy, be extravagant, think elaborate!
I know 5 pole skewed motors are good but...

Ideas: Ball Bearings, 12 pole SKEWED, ?brushless?, etc

See what you can think of

pancake motors not allowed

Q: What are those marklin "sine" drives, are they some kinda stepper motor?

[Jim Banner]

More poles, skewed armature, flywheels - they are all ways of reducing cogging.  So why not just eliminate it completely and go straight to coreless motors?  The cooling problem is not insurmountable.  A small fan running freely on the coreless motor's shaft would take care of heating, even when the coreless motor is stopped.

Slow speed, high torque means large diameter.  But large diameter is incompatible with small boilers and narrow hoods.  The only way you can use short, fat motors is by mounting them sideways, which is the definition of pancake motor.  Small diameter means high speed to generate enough power.  That is the purpose of gears - to reduce the speed to more usable levels.

Lets consider how we could improve steam locomotives still using high speed motors.  If cost is no object think in terms of double reduction gearing.  First stage, concentric with the motor, would be a planetary gear box, totally enclosed in an oil bath.  The planetary box would also serve as flywheel.  The output of the planetary would be belted with a cogged belt to a jack shaft driving all the driving axles via multi-start worms driving pinions, one per axle.  Multi-start worms run smoother and quieter but have limited reduction, thus the planetary gear box as a first reduction step. Gear drive to each axle would be rather more costly than using side rods, but no worries about going out of quarter as the crank pins wear and no problems with independent suspension of all the drive wheels, greatly increasing traction.

Fantasy?  Or Revolutionary?  Before Atlas and Kato got together and produced the Atlas/Kato RS-3 diesel, such performance was fantasy.  When they actually produced it, it was revolutionary and caused changes in the industry from which we are still benefiting today.  The revolution in steam locomotives came with the Bachmann Consolidation.  It set standards for others to strive for and there have been evolutionary steps ever since.  I don't know if we are ready for another revolutionary step quite yet, but one of these days it will happen.  It is hard to imagine better performance than we have right now, at least in terms of smoothness and low speed operation, but developing a drive that will allow equal distribution of weight across all the driven wheels may well be that next revolution.

Jim     

[us trains]

 Google (Marklin softdrive sine motor) a very interesting article. Bryan

[jonathan]

They say there is nothing new under the sun.  When looking for the perfect motor for torque and smoothness, also consider how power is transferred to the drive wheels.

My figures may be off a little as I'm writing this off the top of my head.  Today's HO models reduce the motors RPMs to the wheels in a 14:1 up to an 18:1 ratio.  Imagine the torque and pulling power if you doubled the ratio.  This was done in the past.  Old brass locomotives used a reduction ratio of 28:1 up to 33:1 (estimates may be off a litttle).  This is how they managed to get a smooth running locomotive which could move the large weight of the brass along with the train itself.  Granted it was noisy, but it worked quite well.

Now imagine taking a modern motor and flywheel placed into the higher ratio reduction gears of a brass locomotive.  Not only is the locomotive quieter (with a little tinkering), but you have gained a model with 'pull-the-paint-off-the-walls' characteristics.  Plus, the locomotive would run at more prototypical speeds.

Today's quality motors (like the NWSL types) can run for decades, turning high RPMs, as long as you take care of the drive train (maintenance).  Other parts usually wear out before the motor. They are already sufficiently quiet (opinion).  I would be hesitant to buy a motor that costs more than the locomotive as purchased new.  However, the coreless motor does sound intriguing.  I'll bet they are pricey.

The trick is fitting the largest motor possible into the space available.

Just an opnion from someone who has tried it.

Regards,

Jonathan

[Nathan Jahreis]

Yes gear ratios help allot! Does anyone remember those good old roundhouse box cabs? With mine I can crank up the ole troller and she top's out at about 15-20smph, but she sounds like she's got "pure dc sound".  That old technology of strait cut gears, wish I could get some helical's for it.

[Jim Banner]

How about Ernst gears for Athearn locomotives?  I tried them.  Once.  The low speed performance was good.  The noise level was outstanding.

Jim

[NarrowMinded]

I found this little gem, only draw back is the 3v motor, but with 3v applied it has so much torque you can not stop it. and with grease on the gears the noise level is not to bad.

I've been wanting to build a small layout that's more then a circle but the grades always get me, I can add weight for traction but then the slow speed performance goes away, this just might be the cure.



NM-Jeff

[Nathan Jahreis]

I found this little gem, only draw back is the 3v motor, but with 3v applied it has so much torque you can not stop it. and with grease on the gears the noise level is not to bad.

I've been wanting to build a small layout that's more then a circle but the grades always get me, I can add weight for traction but then the slow speed performance goes away, this just might be the cure.



NM-Jeff

What is that?, is that a Christmas tree ornament spinner? You must have some ornaments that weigh 25-50lbs

[NarrowMinded]

It came out of a husky powertek screw driver, the whole set is less the $10.00

NM-Jeff

http://www.homedepot.com/buy/tools-hardware-power-tools-specialty-tools/husky-husky-13pc-powertek-precision-screwdriver-set-149160.html

[Santa Fe buff]

Hmm, VERY interesting.

I wanna try to work with engines now... I wonder if...

DARN IT! I'm supposed to clean my room tonight, not try tinkering! 

Cheers,
Joshua

[jward]

when jim mentioned double reduction gearing, it immediately brought to mind the ernst gear sets once sold for athearn locomotives. these accomplished double reduction by halving the thickness of the gears, and using shoulder gears to transfer the torque from one set of gears (the ones connected to the worm and drive shaft) to the other set (which drove the wheels)..... it changes the gear ratio fron 12:1 to 32:1  and cut the top speed in half. i thought they performed much better than the exalted atlas-kato rs3 or anything else out there at the time.

to-day, of course, you can program most decoders to get the same speed response. but double reduction is possible and practical.

[ebtnut]

I might point out that the Faulhaber Micro-mo coreless motors could be equipped with a variety of gearheads with different reduction ratios.  I remotored an old Gem EBT HOn3 2-8-2 with such a motor and a 3.45/1 gearhead in front of the original worm, which made it a very nice-running model compared to the &*%* Mantua open-frame motor it came with that stuck out the rear of the cab to boot.  Not sure at the moment of the availability of these motors.  Someone here on the board probably does. 

[Jim Banner]

Faulbaber is still busy producing motors over in Switzerland.  Check out their website at

http://www.faulhaber-group.com/n110411/n.html

Jim