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Discussion Starter · #1,001 ·
I suspect after the word got around that everyone and their brother was claiming the nose was broke and asking for a replacement, just to have a spare. 😅
Lionel acted the same way when I tried to get a replacement pilot for their Legacy 4-6-6T, after it arrived with the pilot steps broken off on both sides. It was a widespread issue and many persons complained. It was due to the poor package design. I sent photo documentation, but they refused to send the part. I bought one a few months later after they showed up on their parts website…

Tom
 

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Discussion Starter · #1,006 ·
WOW, looks like my PRR freight train will get longer! I'm running out of yard space to park these, can you come down and add a few tracks to my yard? :p:p
Well, I could relieve you of some of your locomotives…that will make room for you!

Cars shipping Tuesday.

Tom
 

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Not a lot of train projects for me in the summertime but still do a few small jobs now and then. I picked up these Weaver E8s last year and installed TMCC and the fixed pilot on the leading A unit. Weaver omitted the stirrups on these so I added some from MTH and Lionel. Waiting for parts from Lionel delayed this part of the project.
These engines came with 4 large motors which I did not recognize. I assumed they might be current hogs like Mabuchi 550s and 555s so I put a Cruise Commander in each A unit. Lashed up they drew 2.4 amps total running light. Then tried running all motors from a single Cruise Commander and found they then drew only 1.2 amps. So I am in the process of replacing the second Cruise Commander with just a motherboard for the R2LC and audio boards in the trailing A.
I have only added the details below the shells. The shells themselves were detailed by the late Bob Milli including all the grabs and stacks. The paint looks factory but these are actually repaints by him. I was unaware of his work until I obtained these.

Train Vehicle Rolling stock Railway Rolling


Pete
 

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Those look great Pete, interesting observation about the Cruise Commander current draw. For four motors, I'd consider tethering the bridge rectifier and bolting it to the chassis for better heat dissipation. The weak link for the Cruise Commander with higher loads is the bridge rectifier. It gets leaky at high temperatures and that takes out the driver FET's.

Jon Z. dropped that little pearl on me, it does make me wonder why they didn't arrange for the bridge to have heatsinking...
 

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I am was aware of the bridge issue and its been removed and mounted to the frame. This is the third MU setup running that way including my 6 motor K-Line E8s powered by a single Cruise M. That last one is still being dyno tested for maximum number of cars. I have to find a place where I can use all 22 of my Lionel passenger cars.

Pete
 

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Stately lookers for sure.

Any theories on why two control units (Cruise Commander) with cause double the amp draw? I have no knowledge of the new control electronics (TMCC, et. al.). But I'd guess the modules themselves draw minimal current compared to the motor loads.
 

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Stately lookers for sure.

Any theories on why two control units (Cruise Commander) with cause double the amp draw? I have no knowledge of the new control electronics (TMCC, et. al.). But I'd guess the modules themselves draw minimal current compared to the motor loads.
My theory is multiple drivers are rarely in perfect sync. That causes the engines to fight each other. Lionel gets arounf that problem with back drivable gears but a lot of earlier engines don’t have those mechanics. With one driver all the motors get the same voltage applied.
My six motor UP E8s only draws 1.4 amps running light. Of course total stall current is about 13 amps so protection is needed.

Pete
 

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My theory is multiple drivers are rarely in perfect sync. That causes the engines to fight each other. Lionel gets arounf that problem with back drivable gears but a lot of earlier engines don’t have those mechanics. With one driver all the motors get the same voltage applied.
My six motor UP E8s only draws 1.4 amps running light. Of course total stall current is about 13 amps so protection is needed.

Pete
My thinking was similar. But DC can motors are natural transmissions. If one was driven faster (higher voltage) than another, the higher voltage motor would just bear more of the load. Thinking a little further, and, assuming the electronics provide pulse width modulation to control power, one could be on while the other is off - out of sync. But I'd think the mechanical inertia of the drives would absorb that. Can the modules detect overspeed and reverse polarity to slow and engine running faster than commanded? That would explain it.

What's the definition of "back drivable gears". The ability of a worm drive to be rotated by the wheels?

And why is the rectifier the weak link? Non-optimum part for the job. I would think the drive IC's would be the weaker link. Or is it just the lack of heat sinking where the drive ICs have some.

All academic on my part as you have the solution. Just very curious on the inner workings of the system, you know, a little kid's "why" :) . Sorry to belabor the issue.
 

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Yes a back drivable engine you can push down the track. I forgot the number but it has to do with the angle of the motor worm and worm gear. The fighting is due to cruise trying to compensate for speed differences. Sometime I will turn Cruise off on two engines and see if it makes a difference.

Pete
 

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You can use the nudge feature on the Cruise Commanders to match the speeds, that should greatly reduce any fighting to match speeds. Obviously, if the gear ratios aren't the same, this advice doesn't work.

Truthfully, I'd have to see this to figure out why the same engines with two Cruise Commanders would behave that way since it doesn't appear to be a gear ratio issue.

And why is the rectifier the weak link? Non-optimum part for the job. I would think the drive IC's would be the weaker link. Or is it just the lack of heat sinking where the drive ICs have some.
The FET drivers are capable of handling many amps, typically 15-20 amps for the drivers used on these products. The bane of the FET drivers is reverse leakage currents from overloaded DC power supplies. Even a small amount of reverse voltage leakage appears to have a major effect on the relability of the FET drivers. Beefing up the rectifier performance with a heatsink is a major improvement. It's also why many of the Legacy models have a tethered bridge on their DCDS.
 

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Using the nudge feature helps. My experience is limited to three different MUs. Maybe there is a method to get current draw down to a point that matches a single driver.
I am more motivated to use the least number of components to achieve the desired results, especially with prices nowadays.
BTW actual current draw for the four Weaver motors is closer to .8 amps. The higher number was due to the .3 amps used by the TIU in the current path and quiescent current of the sound and receiver boards.

Pete
 

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Pete, I'm in total agreement. With a tethered bridge there's no reason at all to use two Cruise Commanders when one will do! Since they're going for $150/ea nowadays, eliminating an unneeded extra is a nice cost savings.

Another bonus is, the second unit never gets out of sync with the first, in command or conventional. Those wires between units always call the correct tune! :p:p
 

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Discussion Starter · #1,018 ·
A bit further with the striped paint scheme for the Raritan River boxcar. Using Big Jim’s suggestions, I achieved better results. I just need to work on the paint on the doors. The ribs make things difficult.

Train Vehicle freight car Rolling stock Locomotive


Train Wheel Rolling stock Vehicle Railway


I have a request from another collector for a RR boxcar in 0-27. I have a couple being stripped now and they will get the same paint scheme…

Tom
 
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