Rack loco

P

Philbahn

Registered
Country flag
Having problems with my electric rack loco.(F O red one)
Been running lumpy. Noticably when going down hill.
Explored the gears . Nothing wrong.
Then the wheels and found the idling rear wheels to be slightly out of quarter causing a momentary locking.
Anybody else suffering?
Was just going to try it but it is now throwing it down
So testing will have to wait
 
After exhaustive testing, I can confirm that the quartering was where the problem lay.
So if your rack loco is suffering the same look at the conrods and see if you can spot where the "tight "spot is .
I held one wheel with a pair of pliers and put a pair of narrownose pliers into the spokes and just eased them round. It might only be 1/2 a degree but it works
 
I'm not sure but phil, but was it running jerkily down a slope?
if so i think i need to look at Sandys...
 
That what I said above.
When it comes down the hill it judders and jerks.
Or at least it did:thumbup::thumbup:
 
The rack loco on the LGB track at the Bredgar & Wormshill Light Railway yesterday was doing exactly the same thing when running downhill.....
 
i have had a new out of the box rack have the quartering issues and is easily corrected
by tkaing it open and adjusting
-and im not even sure why this happens as only the front axel is worm driven and the trailing is a dummy pushed by the rods

and all 3 of my racks -2 electric and one ballenburg-jerk a bit downhill-in direct relation to the steepness and load -only the rack is workign to hold the train and because of the singe tooth design-its not as smooth

ive come to be very cautious with extremes as parts for these are hard to find-especially the drive axels
 
We bought ours at LGB so it was straight out of the box like you say.
It has always done it from new . I just wonder if dead on quartering is causing the problem in view of the idling wheels. Don't forget the intermediate wheels which again aren't drinven.If they had been driven this issue would never have arose.
stevedenver said:
i have had a new out of the box rack have the quartering issues and is easily corrected
by tkaing it open and adjusting
-and im not even sure why this happens as only the front axel is worm driven and the trailing is a dummy pushed by the rods

and all 3 of my racks -2 electric and one ballenburg-jerk a bit downhill-in direct relation to the steepness and load -only the rack is workign to hold the train and because of the singe tooth design-its not as smooth

ive come to be very cautious with extremes as parts for these are hard to find-especially the drive axels
Click to expand...
 
A few years ago Casey Jones asked me to look at an example of this model running on the CFR.
The rod on one side was bending rather than rotating. If I remember rightly the cure was to loosen/remove the screw on the idler wheel. It would seem that quartering and general alignment is a bit more critical on this model compared with most of LGB's range.
 
Think your rght Neil.
Wonder if the loose holes play a part as well. Thats why I said the quartering needs adjusting on the nde wheels


Neil Robinson said:
A few years ago Casey Jones asked me to look at an example of this model running on the CFR.
The rod on one side was bending rather than rotating. If I remember rightly the cure was to loosen/remove the screw on the idler wheel. It would seem that quartering and general alignment is a bit more critical on this model compared with most of LGB's range.
Click to expand...
 
It is almost prototypical, on the Achensebahn downhill it is possible to feel individual jolts from the drive on the loco. Slightly uncomfortable, it must cause a great deal of wear on the bearings.
Uphill it is smooth with no jolting.
 
I had a red rack loco back in the early 90's and it ran fine for two days at an exhibition on a inclined rack line, by the end of the second day I had quartering issues. I had to adjust the quartering, then applied a spot of loctite;- did the job!! Also had the same problem a couple of years later,with a Blue/cream Schollenbahn loco:--- same remedy!! Alyn :thumbup:
 
I'm having this exact problem with my rack loco when it descends. I'm very pleased to have found this old thread. My problem, however, is that I don't quite understand the solution that's been posted. Would someone be kind enough to explain the process to a 'layman'. Loosening screws, holding a wheel with pliers etc... leaves me a bit baffled and I'm reluctant to just have a go for fear of cocking it up.
 
remove the bottom plate from the gear box. this has five screws, on the underside of the loco.

it has been years, so my memory may be off, but
as I recall,

you will find ONLY the forward axle is driven by a single worm, and the motor points downward, ie from roof of loco to track.

This axel should be fine. the rear axle however, should be moved (rotated) so as to have no tension in the drive rods on both sides of the loco, ie a touch of play. as noted, check to see that the screws in the rods are not too tight.

there should be a mirror symmetry in where each wheel , and each motor counter weight drive wheel (the ones above the wheels) sit, on each side.

I know this is vague, as is my memory, but this seems to be what I did to eliminate the jerkiness. This TOO, assumes, there is NO excessive wear to the front axle drive teeth, OR, the areas in which the axles sit in the gear box. This should not be a concern at all, UNLESS your rack loco has had a good deal of wear and use, ie heavy loads, steep grades.

be mindful of the plunger contacts against the inside of the wheels when you take a peek. they need to be pushed into the housing (thin flat screwdriver) before resetting the axle into the gear box, should you pull it out.

work over a towel to avoid bits bouncing into unknown places.

pay attention to everything in its place at the time you open it. make a mental note of where contacts are, etc. so you may confidently reassemble.

as with many quartering issues, you may need to try a few times before its perfectly aligned.
 
stevedenver said:
remove the bottom plate from the gear box. this has five screws, on the underside of the loco.

it has been years, so my memory may be off, but
as I recall,

you will find ONLY the forward axle is driven by a single worm, and the motor points downward, ie from roof of loco to track.

This axel should be fine. the rear axle however, should be moved (rotated) so as to have no tension in the drive rods on both sides of the loco, ie a touch of play. as noted, check to see that the screws in the rods are not too tight.

there should be a mirror symmetry in where each wheel , and each motor counter weight drive wheel (the ones above the wheels) sit, on each side.

I know this is vague, as is my memory, but this seems to be what I did to eliminate the jerkiness. This TOO, assumes, there is NO excessive wear to the front axle drive teeth, OR, the areas in which the axles sit in the gear box. This should not be a concern at all, UNLESS your rack loco has had a good deal of wear and use, ie heavy loads, steep grades.

be mindful of the plunger contacts against the inside of the wheels when you take a peek. they need to be pushed into the housing (thin flat screwdriver) before resetting the axle into the gear box, should you pull it out.

work over a towel to avoid bits bouncing into unknown places.

pay attention to everything in its place at the time you open it. make a mental note of where contacts are, etc. so you may confidently reassemble.

as with many quartering issues, you may need to try a few times before its perfectly aligned.
Click to expand...
A good tip is to take digital snaps at each stage of the process and have some small pots handy to put screws etc in.
 
Steve, many thanks for your reply. I'll have a go and see what happens. I've had the thing apart a few times but its the quartering that I'm a little fearful of. I'll report back with the results.
 
Well, it worked. A vast improvement on the descent. There's a hint of judder but nothing like the jarring there was before. I was surprised at how little rotation, of the wheels on the rear axle relative to each other, was required. Thanks again. This is a great forum.
 
Yup!
Glad it worked.

I love the electric racks, slow speed, nice full brightness lights, odd boxy turn of the century electric look.
 
Orgiva said:
Well, it worked. A vast improvement on the descent. There's a hint of judder but nothing like the jarring there was before. I was surprised at how little rotation, of the wheels on the rear axle relative to each other, was required. Thanks again. This is a great forum.
Click to expand...
We had lots of problems with rough descents on the Ruschbahn Rack Line, I wonder of it was the same issue that you have now sorted. Will never know now sadly.

EDIT
Though I do still have the Rack Loco so can check out that quartering! Perhaps the mystery of lumpy running will be discovered after all.
 
Last edited:
Thanks Steve for cure and Mike for bringing this thread to the fore again. I've got an old 2146 Schöllenenbahn rack loco that's only been on the rack once during initial testing. It did pull its mating passenger car around the Christmas tree a few years. I'll have to keep an eye out for the quartering issue when I finally get around to putting a rack line in the backyard.

Phil S.

Edited 2/18 to correct 2046 to 2146
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom