Nikki & Frank S, loco to tender interconnect..

[curtis]

From what I can tell, there is only a single decoder (in the tender). The tender will run without the body. The body won't respond to any function without the tender so I'm not sure editing the max/min speed CVs will help? I'm assuming the suggestion was to calibrate the tender and the body separately in the event they had a decoder each?

Pickup continuity seems fine but Phil's suggested triggered a thought. I identified the motor cables and tested with direct DC from an LGB start set and found the body itself isn't running smoothly - there is a certain jerkiness and low voltage gets no movement (although I can hear the motor trying). To get the wheels to turn at a medium speed ends up drawing just under 1A which feels too high given my experience with LGB locos. I opened up the motor block to have a look can can't see anything odd other that what looks like fine plastic filings around the middle wheel set. I gently lifted the wheels and ran the motor without load and seems to spin freely.

I reassembled but still seem to be in the same situation (not withstanding anything I may have done to make it worse...)

 

[idlemarvel]

If it's like the mfx version I had, there is one decoder in the tender which controls both motors with a plethora of wires between the two units, so you can't run loco and tender separately and you can't independently tune the CV for each motor.

 

[PhilP]

like fine plastic filings around the middle wheel set.

That raises an eyebrow..

Can you take the rods off and see if it runs OK just directly driving the two outer axles?

What colour plastic filings? - Trying to decide what they are from..

PhilP

 

[curtis]

I'm reasonably certain they're from the middle wheel. We're talking very fine and may be a red herring (pun unintended) but not something I've seen before...



Will have a look at taking the rods off tomorrow and report back - a little too tired for that undertaking this evening!

 

[Greg Elmassian]

Exactly... if there is a decoder in each, then set them each to get matched speeds.

Otherwise you will have to resort to adding diodes to the faster one's motor ONLY

 

[dunnyrail]

If Phils suggestion does not do anything.

To my eye the middle wheel looks a little bit out of quartering. Get one side right then look at the other, the crank on the middle (only thing you have to go on with this baby) could be a bit out. Possibly a a couple of gear cogs out of sync between front and rear driver or perhaps the middle flycrank has shifted causing pressure on the chassis hence the red filings.

 

[Paul M]

If Phils suggestion does not do anything.

To my eye the middle wheel looks a little bit out of quartering. Get one side right then look at the other, the crank on the middle (only thing you have to go on with this baby) could be a bit out. Possibly a a couple of gear cogs out of sync between front and rear driver or perhaps the middle flycrank has shifted causing pressure on the chassis hence the red filings.

Good spot, check the rear crank too

 

[curtis]

So I had a look on this today. I did my best to check the quartering and thought I had it lined up but still seemed to have the issue.

I removed the crank and valve gear and left just the drive-rod on. Still seams to have the issue - again, almost no slow running speed. Seems to run find without the drive rod. I noticed the drive rod was under some pressure (the middle wheel is turned only by the rod) so I rechecked the quartering.

This is it reassembled. It seems better (maybe it was the quartering?) but it still seems to have a bit of a lul every rotation and seems to take a few V

 

[PhilP]

I know there is a lot of slop in the motion, but it looks like the rear axle may be one tooth 'out' of quarter?

If you look at the still at the end of the video, it appears to be slightly out of alignment to the other counter-weights.

PhilP

 

[dunnyrail]

I know there is a lot of slop in the motion, but it looks like the rear axle may be one tooth 'out' of quarter?

If you look at the still at the end of the video, it appears to be slightly out of alignment to the other counter-weights.

PhilP

Do you know I was thinking that as well, that last tooth can be a pig. Which way? Get it wrong and you are 2 out!

 

[curtis]

So I did look into this again and I feel like I've got the best quartering I can. I tried moving it back 1 - it is noticeably worse. I put it forward 2 (+1 to restore what I had, +1 extra to go the other way and end with the same thing - I can hear the motor struggling to turn.

I'll give it another shot after I get back from our afternoon walk!

 

[Greg Elmassian]

the side shown in the video has no quartering issues, how about a video of the other side...

I think you have a bind somewhere... if you leave the drive rods off, is it perfect?

greg

 

[curtis]

Here is a video from before I tweaked the quartering. You can see it running without the drive rods etc (from 46 seconds onwards). The only thing that seems odd is the back wheel seems to wobble a bit?

 

[dunnyrail]

Here is a video from before I tweaked the quartering. You can see it running without the drive rods etc (from 46 seconds onwards). The only thing that seems odd is the back wheel seems to wobble a bit?

Not sure if that back wobbly wheel would be ultra problematical, but it could just be what is not helping. The rods would be just a little bit out of sync with that, has the loco ever been dropped to your knowledge. Oh yes keep on slower running please, helps to see issues better.

 

[Greg Elmassian]

stepping through the video... the quartering looks a tiny bit off... remind me which axle is driven? (moves by gears)

it looks a bit out of quarter....

also the last driver journal looks worn, that is allowing the last axle to "bounce around".... and maybe causing the quartering to look a bit off..

Greg

 

[PhilP]

Can you post a photo of the last (rear) axle with the bottom cover off the block?
That wandering makes me wonder if the rear axle gear is worn, or not fully meshed with the idler?

PhilP

 

[Greg Elmassian]

Phil, run the video and watch the last axle bounce around in the "journal"... pretty clear..

 

[curtis]

The first and last wheels are driven. The middle wheel turns only via the drive rod itself and doesn't seem to have any drag resistance that I can tell.

As far as I know, it hasn't been dropped. I'm almost certain it was new when I bought it (bought direct from a retailer) and it's barely been run while I've had it. The rough running feels like it has always been a feature and it put me off running it too much which is a shame because it's one of my favourite looking locos.

Here are a couple of photos requested along with a video of me (attempting) to quarter the loco:

EDIT: Gave it a quick run outside to test and it seems to be better. However, I noticed that on curves (R3) this is some vertical movement of the loco with the wheels rising a couple of mm off the rail. I noticed there is very little horizontal movement in the middle wheels compared to some of my other locos with 3 axels (Spreewald). Is this expected in this model (and it explains why it struggled so much with the parallel crossover with x2 R1s? Only seems to happen on curves (can't see it noticeably on the straight).

I'm wondering if I've been seeing both a quartering problem and this acting together?

 

[Greg Elmassian]

I see that wheel lifting off the track... this is on straight track, right?

 

[idlemarvel]

Is the wheel/axle with the issue the one with the traction tyre? I had an issue with a U class 0-6-2 once with a "bouncing wheel" where the traction tyre wasn't seated properly.