Rough riding - Anything I should specifically look at?

[Sir TophamHatt]

I've a train that rides rough  It's like something bumps the whole bogie on that side at one bit of the rotation.

 

Is there anything I should look at, apart from the cogs? I don't think it's those as I took each wheel off and it still did it.

 

Thanks

Edited March 3, 2018 by Sir TophamHatt

[Gordon A]

What sort of engine are we looking at?

 

Gordon A

[34theletterbetweenB&D]

 The problem description is too vague to be of much help. Is the 'bump' lateral or vertical, does it happen once per revolution of the wheelset at a fixed point in the rotation, or is it less regular? Lots more information required. Is the bump constant, present forward and reverse, equally present on straight and curved track, detectable with the item off the rails on flying leads.

...Is there anything I should look at, apart from the cogs? I don't think it's those as I took each wheel off and it still did it.

 Not quite sure how to interpret this information. Removing a wheel will not necessarily take gears out of picture.

[Guest teacupteacup]

Sounds like a split gear issue?

[Sir TophamHatt]

Sorry, my elocution/information giving is rubbish sometimes

 

I'll grab some photos/video later on, but it seems one of the teeth from the cogs doesn't quite meet properly.

 

It's almost like the train runs over a grain of rice. I thought I fixed it but then it started doing it again. Happens forward and reverse at a fixed point in the rotation.

 

The loco is apparently "nearly new" and when looking at the flywheel there's a fair amount of grease still in there and around the cogs; looks new, not old grease.

Edited March 5, 2018 by Sir TophamHatt

[timbowilts]

Sorry, my elocution/information giving is rubbish sometimes

 

I'll grab some photos/video later on, but it seems one of the teeth from the cogs doesn't quite meet properly.

 

It's almost like the train runs over a grain of rice. I thought I fixed it but then it started doing it again. Happens forward and reverse at a fixed point in the rotation.

 

The loco is apparently "nearly new" and when looking at the flywheel there's a fair amount of grease still in there and around the cogs; looks new, not old grease.

 

The "grease" could be the problem, if there's too much of it and it has been there for some time?

 

Tim T

[The Johnster]

The grease/compound lubrication supplied with new models has a habit of drying out over time and solidifying, making it the opposite of lubricant.  I would look at this first unless you are certain that the loco has not spent more than a few months on the shelves in the shop or you think it has been stored inactive for any serious period of time; 'nearly new' sounds like this.  If this is the problem, the grease needs to be cleaned thoroughly out (I use Maplin's rattlecan switch cleaner for this, as the spray is powerful enough to blow most of it away).  Leave the model overnight for the cleaner to evaporate off, and relube with a suitable modelling lubricant applied VERY SPARINGLY.  The model shop that supplied the lubricant will sell you a suitable hypodermic syringe which will help you to apply small amounts in exactly the right spots, which will be shown on the 'Owners Service Sheet' supplied with the model, and available to download online if you do not have it.  Keep the hypo with you modelling stuff and well away from any others in you household used for medical or other purposes for obvious reasons.

 

If the loco still runs rough, have a look at the wheels and pickups.  Do the wheels run true and square to the axle?  If not, a bit of brute force levering correctly applied with an old screwdriver will cure most issues.  Do the pickups bear evenly on the backs of the wheels?  If not, remove the wheels (they will drop out when you remove the keeper plate, the plastic piece that goes underneath them and often holds the pickups in position, held by screws to the chassis.  Don't lose the screws; I stick mine in a lump of blutac to stop them making a break for the border).

 

Still running rough?  Look at the gears and the meshing of them with the motor, especially if the roughness is worse on one direction.  If you can, turn the motor over by hand feeling for the rough spot.  It may be that you can cure the issue by slightly loosening or tightening the motor mounting screws to 'fine tune' the mesh, but if it is a matter of damage in the gear train, the offending gear must be replaced.  These are a drop in replacement if we are talking about plastic spur gears; faffy and fiddly, but not difficult.  If we are talking about worm and cog drive, they should not be worn, but plastic cogs that have been mishandled in the past by a previous owner (this is a s/h model, right?) might be worn and need replacing.  If you are not comfortable doing this sort of more involved work, look at having it repaired by a dealer or buying a replacement chassis.  But this sort of drastic action is rarely needed.

 

I am in the habit of completely stripping, checking, and re-lubing to my standards, any secondhand loco I acquire, and would strongly recommend you to do the same.  What may have been acceptable running to a previous owner may not be to you, and the loco may have been sold on because it was giving trouble; 'nearly new' can cover a multitude of sins!

Edited March 5, 2018 by The Johnster

[chriswright03]

Better headings will always make it easier for people to pick up on the thread rather than just drift past it.

 

I often say Google is your friend but I would advise against Googling the thread title on a shared or company computer!

[Sir TophamHatt]

Here's a couple of photos.




Took the wheels off from that bogie and wiped a bit of grease off.
Put it back, reseated the (don't know the terminology) little stick from the round gold ring to the flywheel (?).

Seems to be okay for now.
Bookmarking this thread though!

 

Is there a site that can tell me the different types of motor?

I understand a ringfield one when I see one, I think.

Edited March 7, 2018 by Sir TophamHatt

[John Tomlinson]

Completely agree with "The Johnster" that any second hand purchase is worth a "look under the bonnet", to check all is well, and that lubrication is appropriate, even if it runs OK.

 

The grease employed by the major manufacturers is a real pain, often it was grossly overdone and gets everywhere, messing up electrical contact with the rail and spreading greasy goo on your track. It also congeals very badly, so much so that a recent purchase of mine had the driving axle stuck solid in the bearing - the loco was around 12 years old, mint condition and never been used. Once cleaned out it ran beautifully.

 

I'm interested to know what loco is shown in the picture, and wonder if it is of a non -UK prototype as I don't recognise the chassis? Glad it now works for you.

 

John.

[John Tomlinson]

Just stumbled on your other thread, answering my question, OBB 2143.

 

Can't help with DCC I'm afraid, still back in the 20th century.

 

John.

[The Johnster]

Here's a couple of photos.

 

IMG_20180307_100700.jpg

IMG_20180307_100735.jpg

 

Took the wheels off from that bogie and wiped a bit of grease off.

Put it back, reseated the (don't know the terminology) little stick from the round gold ring to the flywheel (?).

 

Seems to be okay for now.

Bookmarking this thread though!

 

Is there a site that can tell me the different types of motor?

I understand a ringfield one when I see one, I think.

 

As a very general summary, motors can be broadly divided into 3 types.  Firstly, the 'open frame' motor, the most basic sort (but don't let that put you off; some of them are very good).  The armature is held in a frame with bearings on the shaft at both ends, and the magnet is at the 'back'.  The shaft usually drives a cog gear on one of the driving axles on the loco by means of a worm gear on the shaft; steam outline modes are usually driven in this way, but diesel or electric outline models can be driven by a double ended version with worms each end of the shaft driving cogs on the driven axles of the bogie.  Another version is also double ended but drives both bogies via universal joints.  Some tender driven steam locos have a similar universal joint drive so that the driving wheels are driven by the motor.

 

Secondly, 'can' type, basically an enclosed version of the open frame.  These are very cheap, being mass produced in the Far East, and can be regarded as a maintenance free replaceable item.

 

Thirdly, the 'ring field'.  Originally developed by Hornby Dublo, and taken up in disastrous plastic versions in the 80s by Lima and Mainline, this is mounted transversely in the loco body and the magnets are on the outside.  Drive is through a train of spur reduction gears, and the advantage is that a high motor speed developing a lot of power can be thus geared down at the driven wheels.  In the plastic versions, one sometimes runs into trouble with split gears causing poor running, but at least they are cheap and easy to replace, or they are when the word 'easy' includes a lot of faffing and fiddling!

 

No type is inherently superior, but some are more suitable for some applications than others.