Chuckles51

Hi 

I through mazak rot only a problem that effected older model's i.e a read somewhere some of the ex lima models. as they everyday is a school day. I will go and investigate and come back.

Neil 

Hi all

I forgot to mention that it is the newer model 2011 release from Hornby R3451 so I don't think it is Mazak rot would be the cause  of the problem but thanks for the suggestion.

Neil

hi all

I have a Hornby derailing on a third radius curve . what is happening is that as the front pony truck's rear wheel is lifting up as the loco enters the curve which then leads to a derailment. I have checked the back to back which is within tolerance and all my other locos go round without issues for years. Doe's anyone have any idea's as to what the problem is? Thanks in advance

Kind Regards

Neil

Hi all

Removed the step's and it has solved the problem and goes round the layout fine, thank you all for your help and suggestions.

Neil Cafferky

On 17/08/2020 at 19:25, 34theletterbetweenB&D said:

That sounds like the pony truck screw (or something else) is holding the pony truck in the straight ahead position.

 

First thing to try, slacken off the pony truck pivot screw half a turn at a time, until the pony truck pivots freely, then test run the loco.

Tried This Somewhat worked having had a look at the bottom of the loco again I think the front steps is causing the problem I have attached an Image to see if this helps.

On 20/08/2020 at 13:40, 313201 said:

Hi Everyone, 

 

I am not sure if this has already been suggested so I will offer my apologies now if it has.

 

I  have a Bachmann WD 2-8-0 and I  found that gluing a relevant sized piece of lead to the plastic pony truck has minimised the number of times it derails so I will add another piece to it subject to this being possible given the available space.

 

This does require the spring to be removed as it is fiddly to refit it but also, removing that spring does allow space between the pony truck and the chassis but its not much so any lead fitted in this space will need to be flattened enough so that it does not foul on the chassis.

 

Hope this helps.

Thanks for the Suggestion 

Neil

Hi all

went away and had a look at my WD. What's happening is that when the pony truck reaches the curve it lifts up and hits the bottom of the chassis and jams and comes back down and derails when the last driving wheel reaches the start of the curve (the Curves are second radius ). the driving wheels move freely, the loco to tender coupling moves freely. regarding this "If the spring is correctly positioned does it positively maintain the wheelset in contact with the rail as you lift the front of the loco a millimetre.". I tried this and the loco stayed on no problem. Hope this helps

Neil 

12 minutes ago, 34theletterbetweenB&D said:

Assuming this is the OO specimen rather than the GF N.

 

Several things to check on the loco.

Is the flat spring on the pony truck properly seated? It can get dislodged to one side and then the truck wheelset comes off the rail like a mad thing, and will help the rest of the loco off.

If the spring is correctly positioned does it positively maintain the wheelset in contact with the rail as you lift the front of the loco a millimetre. If not adjust the spring pressure. (Above applies to all Bach pony trucks of this design.)

 

Coupled wheelsets. Are they all free to move independently from side to side, no bent coupling rods or fouling from the moulded brake gear?

Do the sprung 2nd and 4th axles move freely up and down (small movement)? The sprung saddles on these axles can get stuck in old gluey grease at the top of their travel, leaving the wheelset less constrained than it should be.

 

Is the loco to tender coupling free moving?

 

The track.

Does derailment occur only at certain locations, or is it random?

Can you see what is happening

What is the minimum radius you are sending the loco around? (specified for 2nd radius - 438mm - minimum.)

I know what this mechanism doesn't like, old 'system six' points that are well used. Had to take the pony truck off to make it work on these on a friend's ancient layout, shortly after this model was first released twenty years ago (and where did that time go?)

It is the OO specimen. thank you for your reply lot's for me to look into and I will reply once I have tried your suggestions.

Neil 

Hi all

I have a Bachmann WD 2-8-0 which keeps derailing on curves especially the front pony truck - any suggestions?

Neil