Gary - the LL Berkshire derails on the 11" curves on the outside loop as well without any cars behind it. The curves are flat too.
The Bachmann Spectrum 4-8-2 Heavy Mountain has the same driver size and same driver wheelbase as the LL Berkshire. The Heavy Mountain runs fine, but the Berkshire derails on 9 3/4" curves. Maybe I should try to replace the LL drivers with those of the Heavy Mountain...? I would hate to foul up a new-to-me locomotive though.
Where at in the curve is the derailment starting? If it is at the beginning, perhaps it would warrant building a small test track of a curve with an easement and see if you have the same issues. Then you could definitively rule out either the track or the locomotive depending on results. Sent from my XT907 using Tapatalk
It happens on the upgrade yes. Just tested the Berkshire on my oval of Kato superelevated curve track at work (11" and 12 1/2" curves) and it derailed on them too. I almost dont' want to fool with this any more and just sell it on ebay. Why the hell would LL advertise that it will go on 9 3/4" radius curves when it can't?
Absolutely. Where I have run into problems with my Berk derailing is on curving grades (with a heavy load in tow). Cheers, -Mark
I have a small oval of Kato superelevated 11" and 12 1/2" radius curves at work, and it derailed on the 11" superelevated curves. It also derails on the 12 1/2" radius curves coming off the superelevated curves. Something is definitely wrong, but all the signs point to nothing is wrong (track is in gauge, wheels are in gauge, wheels have good lateral movement, etc.) This is frustrating because I WANT to like it, but it has to run on my layout for me to keep it.
I took off the second pair of drivers to see if that would solve the derailing problem, and nope. Still derails coming out of the superelevated curves.
If the loco was still DC I would venture to say take the tender off the loco and run it since both sides of the drivers are pick up. That would absolutely eliminate the drawbar issues. If this still has a retainer at the bottom of the drawbar post and if and the tender drawbar is resting on it could be applying just enough slight downward pressure to cause some lift on what is known to be an already light front. That effect will be slightly exaggerated when on the upgrade even more. One last but simple diagnostic test with no disassembly involved is to put a small ball of Tungsten putty or a small nut on the smoke stock for additional weight on the front and run it slowly and see if the additional weight cures the derail. I favor the Tungsten putty because you can vary the weight to see what gives the best effect and one doesn't have to worry about the nut falling off and possibly shorting the track. There is one other remote possibility that the problem could be with the pilot truck causing a lift and you could try running it without the pilot truck. After this I am out of possible causes and diagnostic ideas from this old steam guy.
I did a test and took off the drawbar completely, as I have wires going from the locomotive to the tender. The front of the 2-8-4 still derails on broad curves like 11" and 12 1/2". It's not the drawbar. I also removed the pilot truck, and the problems still persisted.
My layout is DCC, so I had no way of telling if the problem persisted before the DCC conversion. However, I never took apart the drivetrain for the engine. I left that completely intact and on the engine. So whatever it was like before I bought it, I inherited it.
About the only thing left is to try the weight as I suggested. And just one other thing slipped into my mind which is that maybe the vertical alignment of the front driver set is out. If for any reason the wheels are not set straight on the axle could be an issue. Rare but does happen. However it may not be enough to affect on the straight away but enough to effect on curvature. Run it upside down in cradle and observe the drivers that they are not wobbling and if you have a wheel gauge use it while the loco is running. Now I am definitely out of ideas so unless someone else has anything that hasn't already been checked the next step is to take it out and put it down range for target practice.
The front drivers to not wobble. The other drivers don't wobble enough to cause a derailment. As for the weight, I'll have to find a place that sells tungsten putty. Even if I pack the front with weight on top of the smokestack, it sometimes still derails. I think I'm just going to sell it on eBay as DCC equipped.
If you have already tried the weight I would not go on a hunt for Tungsten putty. However if you do decide to anyway places that carry Pinewood Derby supplies generally have it also any place that is big on fly fishing supplies has it. Also goes by the name of moldable lead. I still think it is something simple that is just being missed.
I want to believe that. I really do. Maybe I'll post a video tonight of what it's doing and how it's derailing.
Success! I was finally able to get it to run around my small layout on 9 3/4" radius curves! I added weight inside the notch on the frame above the second pair of drivers, and added even more weight inside the sand dome inside the shell over the third drivers. This was all even without the shell and pilot. I'm going to add some more weight on the pilot. Maybe I can take you up on your offer John and cut apart some of the plastic pilot and add part of the metal pilot. That would add even more weight. Now I'm debating whether or not to sell it at all.
I'm debating it. My dreams of this thing hauling more than three passenger cars might be far fetching, but at least it goes around my layout.
