Red Caboose GP9 drive

Hi Gregg,

Man, I'm thrilled you're happy!  You just never know how these things are going to work out.  Thanks for sharing the video and compliments.  The do mean a lot to me.

Have fun,

Jay

Before you do anything, buy a tripod.

Now excuse me while I clear the Captain Crunch with Crunch Berries from my keyboard.

That's a fantastic unit!  Thanks for the video.  I'd love to see it again when finished, if not before.

Well done Jay.

Excellent drive, design and execution. A work of art and it runs like a Swiss watch. It's a keeper. Jay sure does professional work. 

Butch

Jay (and Gregg) A beautifully engineered drive train.  Did you need two motors for pulling, or is it a matter of avoiding the extra transfer gear box and long shaft(s) needed if you just had one? 

John,

There's really not a single answer.  The Faulhaber gearhead motors shown are really nice but not as powerful as say a large Pittman.  I've done quite a few locos with a single motor but I did an RSD for a friend with two motors because of the weight.  A single motor wouldn't have been powerful enough. 

After that I wondered if I could fit two of the gearhead motors into a RC shell so the whole thing was kind of an experiment.  I also installed ball bearings to the axle journals and Delrin wiper mounts and phosphor wipers all around.  Everything beyond the gearhead is setup for a 1:1 ratio so everything turns far slower than other drives.  This greatly reduces vibration, noise, wear, etc.  Also, every shaft turns in ball bearings.  

I'm in the process of doing another but it will be standard O Scale.

Hope this answers your questions.

Jay

Erik,

Somebody did on one of the forums but I didn't feel comfortable sharing what Gregg, or anybody, paid me to do something.

If you want to email me off line I can share a basic cost document.

No offense intended,

Jay

Jay

Thanks for the reply

Everything beyond the gearhead is setup for a 1:1 ratio so everything turns far slower than other drives.  This greatly reduces vibration, noise, wear, etc.  

I gathered that.  Seems like a very sensible approach, particularly when you have a belt drive and right angle gear boxes on the axles

John,

Here are some photos of a single motor installation Jay did for me a shortly before doing Gregg's. I'll have a small layout with fairly short trains so single power was fine and I'd rather add more locos if I need the extra power. Same scenario as Gregg's, ball bearing all around, wipers, etc. and performs smooth as silk. Best driver I've ever owned and I've had a few. 

Butch

Gregg, Butch, et al,

Please keep in mind these little Faulhabers are not "Super Duty" type motors.  You're never going to be able to pull say forty cars.  Well, maybe you could with three units but I suppose it will depend on the cars, grades, and curves.

If we want super pullers we'll have to go with much larger motors.  Our Pittman 8000 Series would be great except the hood is too narrow.  I did order a larger Faulhaber to experiment with a more heavy duty model but I'm not there yet.  If the shells were just a 1/16" wider we could install the Pittman.  I've debated on removing some of the material from the inside of the RC model but I don't have a shell of my own to experiment with.  Maybe I should buy one.

Jay

"If we want super pullers we'll have to go with much larger motors.  Our Pittman 8000 Series would be great except the hood is too narrow"

    The motors that came in the RC geeps were pretty good pullers, about the same as a Weaver RS3 or GP38-2. IIRC they were Pitman or maybe a clone. The only problem with the stock locos was the wheels that came on them were sintered iron and pitted badly. A new set of NWSL wheelsets and they ran fine for the money.....DaveB

Dave,

Sorry, I can agree with you there.  The motors had Alnico magnets and are weak but they were cheaper than the good motors so that's what they went with.  The drives them selves were built as cheap as possible also.  I suppose it's somewhat like beauty being in the eye of the beholder or you get what you pay for.

When I talk about a "Super Puller" I'm referring to having one of these models pull 30, or so, cars on it's own.  The stock model won't do it, not so much from a lack of power but a lack of weight.  If you could get enough weight added to pull the cars the old drive couldn't handle the torque.  I know this because I had a good friend that would weight these models (the Weavers too) so they would pull really well.  Truth is, they'd pull for a while but not long because parts would break.

Jay

I am ever so glad that my self-imposed layout limits restrict me to 5-7 car trains.....

mwb,

Not sure what your point is but that seems to be a common issue for me.

Just to be clear, the drives, and the models they're installed in, will probably pull as well, or better, than the originals but that's still not that much.  Again, mostly because of a lack of weight.

Jay

No issue for me on pulling power Jay. You and I discussed this before going forward with the project. I doubt I'll ever pull more than 5-10 cars behind one loco and if I need to pull more I'll run multiple units. I'm quite happy with this sweet running little jewel.

Butch 

Too oblique...

Point is that I find it fortunate that I can use such equipment w/o bothering to address the stock drives; at they sit they meet my specific requirements.  That lets me allocate my time and other resources to those areas and projects to do require "investment".

Okay, I understand that but please keep in mind, the ability to pull a large number of cars really isn't really the goal.  The goal is to pull them well.

Jay

All to true.  But on my small layout where if I turn around quickly I'll meet myself, the bar is set pretty low,  

OTOH, I'm not altogether sure why I even have one of these engines at all - more than a few decades too modern for me!

I know what you mean.  In my make believe world diesels were a failed experiment and never really lived up to the hype.

Actually, I much prefer working on steam.  Here's a PSC SP M4 I repowered.  The motor is a very nice Canon that I got from Rod Miller.  I was saving it for my own use but it was perfect for this little loco so I used it.  The real bummer is, Rod can't get any more from Canon.  Oh well, Sailor Vee.

I just received feedback from the owner yesterday and he told me he's very happy with how well the model runs now,

This model came with one of the Pittman's with Alnico magnets.  Fact is, it could barely pull itself.

Okay, so much for thread drift.

Jay

"The motors had Alnico magnets"

    I don't know,, I never had a reason to inspect them. The locos always did what I asked them to do. They were used on a branchline layout where due to terrain and out and back operation the prototype always ran two locos back to back so each only needed to be able to pull 10 or so cars. After changing the wheels sets the only problem I ever recall from the RC geeps was the plastic step treads had a tendency to get knocked off and need to be re-glued.....DaveB

I agree - am not looking for super pullers.  My layout plan is a small branch railroad switching trains of 8-9 cars max.   My goal is great low speed performance that closely mimics a real engine in a switchman situation - i.e., good crawlers.

OTOH, when I have the grandkids' Lionel Thomas and Area 51 RS3 engines converted to P:48, we'll be looking for drag racing starts and top end speed!! 

With wheelie bars and parachutes?

Jay

Gregg and Butch,

I was concerned about the current being drawn with these motors and I double (or maybe triple) checked the Faulhaber spec. sheets and came to realize I was being way too conservative.  The motors I installed in your models are actually rated for .4 amps continuous.  I know Gregg's draws .4 with two motors so he's only using half the rated current.  This means he can add weight for additional pulling power.

I don't remember how much Butch's loco draws but I'll bet it's less than .4.

The point of all of this it to retract what I said about being a great puller.  They should pull more than the Pittman with far less current.

Jay

Thanks Gregg!  Just know that you can add more weight if you want.  By the way, I made an change to the lines you quoted.

Jay

Now I wonder if we ought to make brass fuel & air tanks along with extra weights for them.  Looks like I've got some experimenting to do on my end.

Jay

The Faulhaber, Maxon and other coreless motors are typically more efficient compared to conventional motors such as Pittman. So you are exactly right that you can expect the same pulling power for a lot less current draw. However there's an important difference with coreless motors - how they respond to PWM drive such as used in DCC. 

Coreless motors can overheat to the point of destruction if used with low-frequency PWM drive. With today's "supersonic" drive DCC decoders this is no longer an issue. But it's really important not to use coreless motors with PWM frequencies below about 16kHz. For example, if one were to drive a Faulhaber off an earlier O scale decoder such as Digitrax DG83, DG383, DG583, one would melt the innards of one's expensive Faulhaber motor in short order.

Don't ask...  

As well, be aware that earlier versions of the NCE D408 (pre "SR") have a CV for adjusting the PWM frequency. With a Pittman or similar motor, the available torque drops away as you increase the PWM frequency. But with coreless motors, the efficiency increases as you ramp up the PWM frequency. So if you have an early D408 with adjustable PWM, set it to the highest frequency before you connect a coreless motor!

As you probably know, coreless motors have been used in European O scale for a long time. The ESU Loksound decoders have motor drive characteristics that are ideally suited to getting the best out of coreless motors. It may be necessary to turn off or lower the BEMF feature of some decoders that are factory-set for conventional motors to optimize the starting off and very slow running of coreless motors.  

Last thought: My rule of thumb that has served me well since I started fiddling with DCC in O scale 20 years ago is: weight your engines on the heavy side, but never to the point where the motor stalls before wheel-slip occurs. In other words, the exact same rule that worked for O scale DC since it was invented.       

Just my 2 cents...       

Pete 

Great post Pete, thanks.