"Sticky" Schools Class

[doug22150]

I have a different issue with my 4th Schools Class purchase, Malvern, from the Collectors Club Spring 2020 Offers I have been running it in and it is apparent that it suffers from a tight spot but only when running round curves. My minimum radius is 300 mm, which the loco. should be able to take with ease. On the straight, running is good but on curves there is a rhythmic "rubbing" and at times the loco. can be seen slowing and surging again as the "tightness" is passed. I have tried running without the front bogie and that completely eliminates the noise, as well as any tendency to "surge"! I've also checked the bogie wheel back to back dimensions, in case they might be rubbing on the valve gear. I think that the problem might be because the leading driving axle does not move smoothly from side to side. It can be felt to almost grate in the bearing (or gearing?) as it is pushed from side to side. This is quite different to the easy movement on the rear driving axle. I have tried lubricating the axle on each side but am very wary about over-lubricating.

Regards

Doug

[Andy Dapol]

Hi doug22150 ,
I also replied to your previous post, so will place it here also.
Hi doug22150 ,
It's tricky without being able to see the model. Certainly 300mm should be OK for this model. My initial thoughts are:

1. Check the alignment of the motion in case it's slightly bent inwards and is binding
2. Check the sideplay of all wheels is free - you mentioned this is an issue with the leading driver.

You are right to not over oil. If a little more judicious movement and check does not reveal anything obvious, unfortunately I can only suggest return to the place of purchase (Us!) or to DCC Supplies for warranty servicing.

[doug22150]

Thanks Andy
I have already checked the motion alignment and can't see anything out of line. I could try removing the cover plate on the underside of the loco., But I know from my previous experience replacing the brass bush under a Schools footplate that it's not easy. You advised that it clips in at the front but I don't want to risk damaging anything!
Regards
Doug

[Andy Dapol]

Hi doug22150 ,
I understand, unfortunately I don't have access to any Schools models at the moment (working from home) so I can't post any photos. If you are at all concerned about going any further then please send it in. Its not an issue which jumps out as being a particular cause, but I'm sure a quick check by DCC Supplies will sort it out.

[doug22150]

Thanks again Andy

[doug22150]

Hi Andy. I didn't manage to remove the cover plate despite levering underneath the front end gently. I also applied a little more oil on the end of a thin wire to the axles. That actually seems to have improved things and the axle does now slide from side to side far more freely. After some further running the slowing and surging motion is much improved, so looking more promising now.

Regards
Doug

[Andy Dapol]

Hi Doug,
Good to hear, sounds like it may have bee something that was a little over tight. Hopefully it should loosen up further during running. Let me know if it causes any further issues.