Hornby M7 and T9 issue

[woodenhead]

I've a few locos mix of Hornby, Bachmann, DJM and Oxford.

 

Recently I've noticed that three of them are beginning to be juddery when running at low speed.

 

All were fine when purchased but one of my M7s and both of my T9s don't like crawling, my second M7 seems ok as do my other locos including a black motor.

 

Track has been cleaned and they run sweetly on a rolling road, it is when they are actually moving that they display a problem. The M7 this evening managed to uncouple doing a Kadee shuffle over a magnet and later did the same to a coach connected to the train with more Kadees as it juddered along.

 

Two things come to mind, wheel cleaning and contacts.

 

Question one, best way to clean wheels, question two anyone know of any contact issues with wipers on these models?

 

Thanks

[TheSignalEngineer]

My T9 was a poor runner out of the box so I decided to clean the backs of the wheels. The problem was not only dirt on the back of the tyres but the pickups themselves were badly adjusted and losing contact with the wheels on some curves.

[DCB]

It they run OK on the rolling road, I wonder if the inside corners of the track are clean as that is where the wheels actually run and pick up.  A lot of cleaners just clean the rail tops.

The T9 has traction tyres and ours has enough trouble staying on the track let alone crawling, bogie and tender wheels are hard to clean so the loco may well only be picking up on one axle.

It could be a controller fault, I use all sorts or voltage control power units which give very smooth running at the expense of poor starting and very slow running, the PWM controllers often give slow but juddery running while resistor units Duette and the like are only generally any good for slow speed when half wave is selected at which point they get lumpy.

[woodenhead]

I don't think it's the controller - it's a Gaugemaster and the other M7 seems ok - but that one has had less use as it trundles back and forth on a push pull.

 

I'll get a cradle whilst i am at Wigan at the weekend so I have have a good peer at the contacts and backs of the wheels - they were all fine when purchased so I am hoping they just need a little cleaning and adjustment.

 

Daft question, but it's a long time since I cleaned wheels with anything but the old Peco wire brush set, what model cleaning products are recommended?

[DCB]

I don't think it's the controller - it's a Gaugemaster and the other M7 seems ok - but that one has had less use as it trundles back and forth on a push pull.

 

I'll get a cradle whilst i am at Wigan at the weekend so I have have a good peer at the contacts and backs of the wheels - they were all fine when purchased so I am hoping they just need a little cleaning and adjustment.

 

Daft question, but it's a long time since I cleaned wheels with anything but the old Peco wire brush set, what model cleaning products are recommended?

 

Not a daft question at all and one which AFAIK been addressed by the trade.  I use the Peco electric wire brush on a dedicated cheap and nasty controller with what I believe is a Peco loco cradle.  Trouble is the cradle tends to remove bits like handrails and the brush is a bit on the big side.  Having a set of different shape tools for the leads, brush, spike, file, and crocodile clip helps as one can use the clip to connect the chassis or a wheel on the tender for 2010 era tender locos and leave both hands free. The tools will of course destroy traction tyres.

 

Cleaning the back of the wheel where the pick ups run is important, as is cleaning the pick ups but be careful, I use a very thin craft knife blade and push the pick up back the absolute minimum as its easy to bend them and lose the tension.

 

The gap is in cleaning the unpowered wheels.  It really needs small revolving brushes or something similar, to clean the treads.   There are some excellent car wheel cleaners available (from Poundland in a pump action bottle) but someone else can find out how much they attack plastics, I do know they do a fantastic job or shifting road grime from car wheels so maybe worth a few drops on a cotton wool bud? 

[Dunsignalling]

Lighter fuel on a cotton bud still works as well as it ever did for cleaning wheels. Quid a tin for the petrol and a quid a drum for the buds at Poundland

 

For unpowered wheels, just hold the bud against one and rotate it from the other end using your thumb.

 

Also check for a build up of dirt/fluff between the wipers and the backs of the wheels.

 

While you are at it, oil the crank pins and axles.

 

John

[RAF96]

The problem with a rolling road is the loco doesn’t have to drag its weight around like it does on the track, just spin its wheels.

 

I have an old Class 56 Ringfield with a dead magnet that will run sweet on the RR but can’t drag itself around a track.

 

Rob

[34theletterbetweenB&D]

...one of my M7s and both of my T9s don't like crawling...

 The T9s have traction tyres, the most fruitful source of rail dirt known to mankind. Retire them, clean the rails, wheels and pick ups of everything else on the layout follwiong the good suggestions above, and see your running problems disappear.

[Right Away]

The T9s have traction tyres, the most fruitful source of rail dirt known to mankind. Retire them, clean the rails, wheels and pick ups of everything else on the layout follwiong the good suggestions above, and see your running problems disappear.

I also have an "iffy" T9 which is not the best of runners.

Never having removed the notorious traction tyres before, will contact still be made with the rail head or do the rear drivers need to be changed?

[34theletterbetweenB&D]

Running on the grooved wheels without traction tyres fitted is a lottery. Some mechanisms tolerate it very well, so if the appearance doesn't offend, you are good. Others though will trip up on points due to what is effectively a double flange - often only in one direction - and then you are looking at fitting replacement metal tyred wheelsets. Potential difficulty there is what options are available. Never had occasion to fiddle with a T9, so cannot offer any specific advice on likely outcome.

 

There will be a significant loss of traction without the traction tyres fitted. Just my opinion, this model and the Schools class could do with redesign now that Hornby have evolved a very satisfactory 4-4-0 layout that does not need traction tyres, as demonstrated on their D16/3.