What are the strengths and weaknesses of both types? I grew up in the age of the old postwar AC motor. I tend to be hesitant about buying can motor equiped engines although I have some MTH engines that run pretty nice. Somebody give me the lowdown on this. Is either better than the other? I feel a little more safe with the old AC. You guys always give good advice to one who is less informed and it's greatly appreciated, Mike.
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This is all going to depend on how you operate your trains, and what you are looking to get out of them...there’s differences in the quality levels of both.....for some of us, large Pittman can motors are the way to go in scale stuff, it gives us way better finer control than any old school open frame AC motor ever could.....upgrades for can motored locomotives are far superior than what’s available for AC motored locos. Realism is easily achieved with can motored appliances vs. the AC equivalent.........we now enjoy realistic low speeds set with cruise even on grades and heavy loads thanks to can motors.....but, if whizzing around O31 curves, listening to the buzzing e units and smelling that wonderful smell of ozone is your thing (sometimes it’s mine too) then, let her rip tator chip.......it all depends on what your looking for your railroad to do....ain’t no right or wrong....obviously, DC can motors can run longer than AC motors due to the nature of the AC motors wanting to make heat, but again, that’s debatable dependent on what loads your asking it to do...and the roles could be reversed, say if you ask a 736 to pull 5 cars for 30 minutes, vs. a Railking equivalent pulling 20 cars for 30 minutes............Pat
My personal preference is for can motors for many of the reasons Pat mentioned. I can get low speed, cruise, low power consumption, and quiet operation. I'm also a fan of the great sounds of modern locomotives, and I don't want the growl of the AC motor competing with my sound output. 
Finally, can motors are maintenance free, you don't have to do anything to them for the life of the motor. With AC motors, there is brush replacement, commutator cleaning, lubrication, etc.
Can motors are far less expensive to produce and since all electronic control systems output DC, it's a better match. AC universal motors in our locos did their job for years, but technology and economics just caught up.
The question is, which train manufacturer will be the first to go with brushless DC motors? 
From my experience the only AC open frame motored locomotives I like are F3s, GP7/9s with separate trucks/motors, FM Train Masters, and NW2s with separate trucks/motors. They are all scale sized and run well. Not as slow as modern can motored locomotives but well enough I still run them with modern stuff. I don't care for any of the other locomotives powered by AC motors. All my steam locomotives are scale pieces powered by Pittman motors.
I like to run my trains at slow scale speeds. The old 3-pole AC Lionel motors just were not smooth, but in fairness they were also geared higher (fewer motors RPMs to wheel RPMs).
This would be a non-debate if the smaller motors, most of the time Mabuchis......were serviceable....Pittmans are completely serviceable, and Ametek, the parent company of Pittman is fast about getting parts out.......and it isn’t pricey at all to put new brushes and bearings in a Pittman, heck, it’s easier to service a Pittman than it is to do a Pullmor.....I’ve converted a couple 24 volt Pittmans to 15 volt on the cheap.....the original owner of Pittman, from what I remember was an O scaler, so it was real easy to deal with them back in the day.....but I have no problem getting service from Ametek, they always seem to answer the phone quickly, and I get in touch with a sales rep who takes my order and processes it right then and there......it’s the fact that models like the railking line, traditional sized Lionel, and dare I say all the vertical motored scale locos are kinda stuck with the Mubachis like the 385s......if they had small Pittmans and set screws, it’d be a better deal as far as servicing goes........Pat
Oddly, I have the only Pittman I've ever seen fail with a bad armature, and Pittman said they didn't have those parts.
gunrunnerjohn posted:Oddly, I have the only Pittman I've ever seen fail with a bad armature, and Pittman said they didn't have those parts.
ummmmmmm......that might have been my fault John, I bought a pile of armatures from them....that motor you were working on has bushings, not roller bearings like we discussed once....there’s a roller bearing equivalent armature that should be available.......difference being, there is one roller bearing pressed on the shaft with a swedged section on the armature shaft.....I sent you a motor for your job, but I can surely hook you up with an armature so you can have a rebuilt motor on the shelf for next time!....😉........Pat
So you bought all the armatures, you dog! Since the same size motor is still being sold, I was a bit surprised they didn't have parts. Of course, maybe I was just corresponding with the wrong person.
Pat, on some of the RailKing locos, the worm gear is not pressed onto the motor shaft. So there's no reason in the world why you couldn't upgrade a RailKing Mohawk or even last year's LionChief Plus Berkshire to a (smaller) Pittman motor. I think the 8692-series is about the same size as the common, crummy RS-385. The flywheel is held on with a set screw, so no problem there. The only issue might be the spacing and diameter of the mounting holes. But you wouldn't know nuthin 'bout that! 
The worm is not pressed on? I've never seen any RK without a pressed on worm!
Me too, I’ve never seen a railking like that Ted......please show us....that’s a new one on me!........Pat
Here's the proof that quality design doesn't have to cost $1000, nor require wide-radius curves. Also, the gear ratios on these babies are 26:1 for the RailKing Mohawk, and 25:1 for the LC+ Berk. With drivers less than 1.25" in diameter. Pop in a 24V Pittman, and where we're going, we don't need speed control! Now, if only there were a way to do something about those darn rubber tires...
Yes - agree with above - good quality can motors run at far less current that open frames. Typically long service life, sometimes harder to replace brushes.
A question - does anybody have sources for larger dual shaft can motors (talking less than but close to 38mm wide/50mm plus or minus in length/ 4 or 5 mm shaft OK. I have a couple of boxes of motors but will blow through those pretty quickly.
Another thing that I'm lamenting is the end of the line for NWSL (unless somebody buys them quickly). They made good sized axle mounted gear boxes - I could not get them to make any more. (originally sold for 'G' gauge)
Jim
When I first got back into the hobby in late 2004, I only knew open frame pullmor motors, I stuck with the early TMCC engines for that reason, now I wish I had ventured into can motors sooner, I have a closet full of in the box engines, and the ones on my layout are being converted to can motors and trucks along with ERR DC Commanders. The only ones I will never touch are my Postwar steamers, and Santa Fe and B&O F-3's from the 50's.
Having the speed control Command and DCS give are so much nicer, and as mentioned by John above, the sounds are excellent.
Ted S posted:Pop in a 24V Pittman, and where we're going, we don't need speed control! Now, if only there were a way to do something about those darn rubber tires...
Sorry, I'm not giving up my speed control! 
Nice that some of the RK stuff has gone with the better drivetrain.
Jim Waterman posted:A question - does anybody have sources for larger dual shaft can motors (talking less than but close to 38mm wide/50mm plus or minus in length/ 4 or 5 mm shaft OK. I have a couple of boxes of motors but will blow through those pretty quickly.
I don't know about "good quality", but the Mabuchi RS555 series comes pretty close to your specifications. There are tons of them available from a variety of sources, you just have to be careful to match your requirements to the motors.
gunrunnerjohn posted:Ted S posted:Pop in a 24V Pittman, and where we're going, we don't need speed control! Now, if only there were a way to do something about those darn rubber tires...
Sorry, I'm not giving up my speed control!
Nice that some of the RK stuff has gone with the better drivetrain.
Ditto, ditto. Speed control has changed the O gauge railroading experience....at least for us Switchers/Operators
Lew
Ted S posted:Here's the proof that quality design doesn't have to cost $1000, nor require wide-radius curves. Also, the gear ratios on these babies are 26:1 for the RailKing Mohawk, and 25:1 for the LC+ Berk. With drivers less than 1.25" in diameter. Pop in a 24V Pittman, and where we're going, we don't need speed control! Now, if only there were a way to do something about those darn rubber tires...
I’ve never seen inside of these, nice to know if they do croak, there’s an option for upgrades....NOW, ....If I could just cram a 9000 series Pittman in there...hmmmmmmmm......😁........Pat
gunrunnerjohn posted:The question is, which train manufacturer will be the first to go with brushless DC motors?
DING!DING!DING!
Brushless DC, aka variable frequency three phase AC induction motor, is assuredly the wave of the future (my Milwaukee drill motor runs on this technology).
Lew
Probably the only benefit with the AC motors is that pretty much anybody can fix them if something goes awry with them. Parts have been around for years and still are in plentiful supply today.
If something goes wrong with a DC motor, depending on which motor you need, finding a replacement or parts could be a nightmare.
Most of my locomotives are can motor equipped (either built as is or converted to like most of my 90's Lionel scale steamers). The only few that still have the AC motors are my postwar (or postwar style) locomotives like the NW-2's, F-3's, Geeps, and small Hudsons or early LTI steamers with RailSounds 1.0 like the scale Hudson.
FWIW: Conversion to can motors with speed control may highlight running issues. I upgraded a 1950 736 Berk & a 1954 624 C&W switcher to ps2, changing the mnotors to can motors. The 624 runs fine. But the 736 was a different story. With the stock pulmor, unless one wants to run fast, it is necessary to keep a hand on the throttle when running at slower speeds, to compensate for grades, etc. With the PS2 & can, when running the Berk at less than 15 SMPH, binding would show up, that did not when the pulmor was in. I spent many months working on it, and even had the New England Superguru look at it, and we could find nothing wrong. Finally dropped that 736 project.
"It's the gear ratio, Brian, it's always been the gear ratio." I'll wager that most of you have never operated a locomotive with a quality motor and gear ratio intended for scale operation (because there really weren't very many made in 3-rail O.) I assure you that smooth, consistent operation can be achieved without speed control. If you're ever in Texas pay me a visit and I'll demonstrate ;-) If you like S.C. that's great and if it's working properly I wouldn't rip it out (unless it was TAS EOB!) But it's certainly not a necessity.
Some years back Marklin offered locomotives equipped with brushless motors under the marketing label of "Softdrive C-Sinus." In appearance and principle it seemed very similar to the prototype Odyssey motor shown by Lionel circa 2000. Maybe Marklin's German spies stole the prototype from the tent at York? I researched this product a little and it seemed that the reviews were mixed. I'm not sure Marklin still offers this drive system. If so, it might justify more research to find out why it wasn't successful. I know brushless motors and rechargeable battery technology have wrought a revolution in the model airplane hobby. Ours is shrinking with a very old demographic; I wonder if it will survive long enough to benefit from mass adoption of these technologies.
Everyone's entitled to their opinion Ted. For the locomotives I can buy off the shelf, speed control is a huge plus. FWIW, I have done upgrades on some Williams brass with a 44:1 gear ratio, and I wasn't all that impressed, by the time you were running around 40 scale MPH, the motor was starting to get loud, it was topped out at around 8,000 RPM! There's a balance between the gear ratio and the running characteristics. Also, I don't care what motor you're running, with no speed control it'll still slow down or speed up on curves and grades.
They both have their strengths and weaknesses. Open frame motors are tough and will last forever, if you keep them lubricated and replace brushes when needed. I have a lot of PW locomotives that are 60 and 70 years old that will run right now, with no problems, if I put them on the track. The DC has performance advantages as others have stated. How long they last only time will tell.
NO problem with can motors, as ALL my excellent LGB and PIKO locos utilize these excellent performers. But I also prefer open frame AC motors for my traditional MTH and Lionel Classics standard gauge reproductions. E-unit buzz and open-frame AC whistle motors are "music" to my ears!
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