Number 6 was delivered from Richmond yesterday afternoon. The standby crew took her for a break-in spin up the line five or ten miles and returned complaining that the pilot truck tended to climb the rails and this resulted in a generally rough ride.
The shop crew removed and inspected the truck for burrs, lubricated and replaced it with no improvement. The shop foreman recalled that the Spectrum 4-6-0 had been delivered with a brass shim spring mounted between the truck connecting bar and the frame. This was missing on No. 6. The shim extends forward the length of the connecting bar, pivots with the connecting bar on the frame mounting screw, and provides slight downward pressure on the pilot truck.
Further investigation revealed that the spring is not included on the 4-4-0's illustrated parts breakdown.
Since the pilot trucks for the 4-6-0 and the 4-4-0 are identical, the spring was temporarily removed from the ten-wheeler and installed on the 4-4-0. Further test runs indicated that this solved the problem and 4-4-0s should probably have this same spring for pilot truck stability.
The Bachmann part number for the 4-6-0 spring is H817X-MT069. The part can probably be fabricated but requires very thin material, otherwise the spring and pilot connecting bar will bind when the screw is tightened.
All's well and No. 6 made her first run up the line this afternoon with the RPO and a coach.
Bob
I have used thin phosphor bronze which is slightly springy for a similar situation. About fifteen years ago I picked up a spool of phosphor bronze, .002" thickness. The width is six inches and it must be ten feet long. I would cut and snail mail a few inches of it to use but it sounds like you are doing ok now.
rikc9
Thanks for the insight. I have had the same problem and it was driving me crazy. It only happened on a Peco crossover. I checked everything I could think of and eliminated my track work and the gauge on the wheels. I have the whole loco apart now for a major backdating bash which includes the replacement of the entire boiler. I will try to deal with the pilot truck problem before I return it to service although I doubt if Bachmann has the spare part you mention in stock but, I intend to give them a call.
Peter Smith, Memphis
rikc9 - Thank you for the offer. I have fabricated a spring using a part from my junk box. So far, it is doing very well. Never throw anything away.
pete - Yes, you can generally eliminate trackwork. Mine is an old layout I built for No. 2 son years ago. It is Atlas snap track - not very good but most everything runs reasonably well on it.
The pilot truck was most affected on curves (18"), and I could find no fault with them. When the engine is going forward, the truck is pushed rather than towed, which contributes to the problem - kind of like pushing on the end of a string.
Bob