What are your thoughts on model locomotive balancing?

[Bernd]

Bernd.......

This is really cool.  I recall a guy in the 1950's put a story in one of the hobby magazines that had a miniaturized Hydraulic coupling that was patterned after a torque converter (less the multiplication) but he was unclear as to how he held the oil in the thing. 

A mag drive is a really cool idea............  Could you say that your locomotive was running on magnetic levitation ? ? ?

Interesting idea.

Thanx
Bob

Hi Bob,

That's the article I'm referencing.

As far as the mag drive is concerned I'm wondering how far you got into looking at what that drive is. It has nothing to do with  levitation. It's sort of a magnetic clutch.

This is the test bench.





I've built one into this EMD TR3 engine set using the torque drive.



Bernd

[Bernd]

I remember reading studies about balancing the weight on a steam loco to get most of the weight on the drivers, but I never heard about doing this with diesels.


dave

It's rather difficult to do on a diesel. Although I think it can be achieved.

Bernd

[jbvb]

I re-worked the driver springing in a 70s AHM (Gem reject) B&M/L&HR 4-8-2. I also added centering force springs for both the lead and trailing trucks.  The loco didn't seem terribly out of balance, so I didn't add weight.  The old MR review (and later writings by others) of the PFM B&M A-41f 4-4-0 say it's way out of balance. Performance got worse when the manufacturer's boiler weight was installed, because it was all over the lead truck.  Not sure exactly what I'll do, but it's on the list.

[Bernd]

The old MR review (and later writings by others) of the PFM B&M A-41f 4-4-0 say it's way out of balance. Performance got worse when the manufacturer's boiler weight was installed, because it was all over the lead truck.  Not sure exactly what I'll do, but it's on the list.

A heavier spring on the lead truck to push up the front might help to balance the engine.

Set the engine on a flat level surface and see if a piece of .0015" feeler stock slides under the rear drivers without any resistance. You'll actually be checking the flanges, but if the wheels are in tolerance, both sides should have the same resistant feel.

Bernd

[deemery]

Well, James, when you figure that out, let me know.  I have one of those B&M 4-4-0 in my big box of brass locos :-) I remember hearing "they ran well, or not at all."  I think mine does run, but it hasn't been out of the box for 10 years or more.  (I was deciding between back-dating it to 1890s, or selling it untouched....)

Bernd, great note on testing driver springs.

dave

[Bernd]

Bernd, great note on testing driver springs.

dave

Thanks Dave. Can't take credit for that idea. Learned that from the British site. I think that's why they call themselves "model engineers". 

They are sticklers for things like that.

Bernd

[deemery]

It's interesting how the hobby has differences on either side of the pond.  The Brits do a lot in small spaces, including their machining and engine building.  I think the North American side has the edge on scenery, particularly with our larger layouts 


dave

[tct855]

Dave!,
           You are talking about the "S" word, S-P-A-C-E.  Americans have space on average to RUN trains so we usually focus on long running trains (while some layout trains are kept smaller because of price of buying 400 cars to fill a large yard)*understandable.

While across the pond "S" word is not so much INSX (in excess) so attention to high detail and lots of Dcc functions fill up small track real quick.  *Those who have diorama's or shelf layouts or switching modules know this oh too well.

As I push farther away from the shore of childhood, I see in the horizon of wisdom, that less is more, however Dcc fully maxed out with lights, sounds, weathering and highly detailed trackage by the foot (rather than the over burden of a mile) pleases me more because I don't have to imagine my trains running down the tracks with all the details my brain can fill in, but rather simply push a button and experience it while all those wooden kits packed with castings and over grown with Woodland Scenics, Noch and others past by at scale speed.    My 2¢.       Thanx Thom...

[deemery]

I think "Americans have space" is a big part of it.  But I suspect there's more to it than that.  Seems to me that more Brits work in craft jobs more than Americans, who are more likely to work for a big company.  Machining skills seem to be more common in the UK than US. 


dave

[Bernd]

Back on page one I made reference to a Hobbytown conical drive. I finally found the pictures. They are pretty self explanatory from the instructions.













I would think after much running that the rubber cone would be worn out. I haven't found any pictures of the chain saw style clutch yet.

Bernd