Lionel Legacy K-4 Gear Issue

gunrunnerjohn posted:

I'd love to see brushless motors come into use in the model trains.  I suspect the need to redesign the electronics for the motor has stopped many in their tracks.

If I recall correctly, Lionel spent a lot of money designing a brushless motor for the then new UP Veranda and PRR PA locomotives. Rumor was over a million dollars. This was advertised as the new Oddessy brushless motor. Was going revolutionize the O gauge market. They were never able to make a motor that was reliable. Word was they overheated causing burnout. After more than a year of delays they dropped it for the Oddessy speed control using Standard DC motors. I ordered the PRR PA A-A set with extra powered B unit. They never ran well in a lash-up until the Legacy System came out with Absolute Speed Steps. This eliminated the A and B units from bucking each other. These engines were way overpriced for the time period at over $900.00 for A-B-A setup. Lionel knocked $100.00 off after the failure of the Oddessy motor. That was the last time I ever rushed into buying trains with any kind of new Technology.

Forest

That was an AC motor, brushless DC motors are very well designed and millions are in use.

As a person among many friends who has a couple of the recent LEGACY light/heavy Mikados (among other LEGACY locomotives with this gearbox design), this is quite disconcerting to me. I really hope this gets brought to attention at Lionel, because this could easily be a fatal error in designing future Lionel product.

We did manage to get driveshaft replacements for the Century Niagara years later, so I guess it's not impossible, but I'd rather not wait a decade or so later to fix a locomotive if something goes wrong without paying a premium price.

I'm hoping this is not a persistent thing.  One issue I believe that surfaces is the motor mount only has two screws, and several I've received for service have had loose screws.  This will obviously allow the worm to quickly wear the brass gear, and it might be part of the reason for failures.

One simple thing you can check is to make SURE the screws are fully tightened.  Truthfully, some blue thread locker wouldn't be out of place on these as well.

Someone earlier in this post mentioned that the K line light Mikado had this reduction gear system.

I was curious and checked mine it has a standard worm and axle gear setup.

Did Lionel add it to the Legacy versions?

The K-Line K-4 had this gear setup, don't kow about the Mikado.  Does the Mikado have the forward facing motor or the more traditional rear facing motor?

If this image from the 2015 catalog illustrating the insides of the Heavy Mikado is anything to go by, I'd say they're still using the K-Line front mounted, rear facing motor design.

gunrunnerjohn posted:

That was an AC motor, brushless DC motors are very well designed and millions are in use.

I stand corrected. Thank you for pointing that out.

Forest.

The Lionel Odyssey motor was an attempt to add cruise to an AC motor  However, I believe that the excessive price was probably a key factor in killing it, it was simply cheaper to use the tach sensor with a DC motor than to try to make the AC motor perform as well.  Another point that I suspect played into the mix was the DC motors are significantly smaller and fit in places the larger Pulmore Odyssey motor would not have fit.

gunrunnerjohn posted:

The Lionel Odyssey motor was an attempt to add cruise to an AC motor  However, I believe that the excessive price was probably a key factor in killing it, it was simply cheaper to use the tach sensor with a DC motor than to try to make the AC motor perform as well.  Another point that I suspect played into the mix was the DC motors are significantly smaller and fit in places the larger Pulmore Odyssey motor would not have fit.

However if they stayed with a DC motor why not use the well established brushless DC motor? Yes you can drive them below 55RPM. I think it is the price of manufacturing changes with China. 

I have no idea why brushless wasn't considered, so you'll have to ask Lionel that question.

Yeah just a lot of guessing and contemplating the meaning of life. lol

Some manufacture will eventually evolve.