I have 2 of these engines, one works fine, the other has a problem. On the flat the lopping was not very noticable, but on the grade at slow speed it was VERY noticable. In addition it did not have the traction my other 2-8-0 does, slipping with as little as 4 cars on my 4% grade.
I decided to investigate as to why it was "lopping."
I had previously discovered that only the 2 middle driver sets are geared. The 1st and last driver sets are linked to the 3rd driver set with the side rods. Hmmm So I "lightly" lubed the siderods and driver axles. Improved it a bit, but did not eliminate the lopping.
Tonite I discovered that on my problem engine, the engine sits on the 1st and last driver sets. The middle 2 geared driver sets are a "hair" above the rail. I discovered this when I slighly pushed the engine forward and backward on the rail. The 1st and last drivers would move, but not the middle 2 geared drivers. ah ha!!!
This results in the gears drivers not having traction to the rail. And this explains the lopping action. There is no track contact for the geared drivers, only the siderod on the 1st and last driver set. Also this explains why this engine doesn't pull up my 4% grade, the traction tire on the 3rd driver set is not able to grip the rail.
I also discovered that my engine is not even balaned on the 4 wheels of the 1st and last driver sets. It wobbles when rocked by hand, and visually I can see 1 wheel rock.
The other problem was a clicking sound. There is a pin behind the sliding piston assembly (I need to learn the names of these parts) that sticks out a "bit" too far and will sometime hit the siderod of the lead driver. This might be the "thump" that others hear.
While I don't like what I found, at least now I know the problem. I think this one has to go back to Bachman, as I don't have a mill to fix the frame, nor am I good enough for the fine machining needed to fix the wheel contact problem.
Ah the limitations of N scale, and not being able to spring each driver wheel.
Gary
I decided to investigate as to why it was "lopping."
I had previously discovered that only the 2 middle driver sets are geared. The 1st and last driver sets are linked to the 3rd driver set with the side rods. Hmmm So I "lightly" lubed the siderods and driver axles. Improved it a bit, but did not eliminate the lopping.
Tonite I discovered that on my problem engine, the engine sits on the 1st and last driver sets. The middle 2 geared driver sets are a "hair" above the rail. I discovered this when I slighly pushed the engine forward and backward on the rail. The 1st and last drivers would move, but not the middle 2 geared drivers. ah ha!!!
This results in the gears drivers not having traction to the rail. And this explains the lopping action. There is no track contact for the geared drivers, only the siderod on the 1st and last driver set. Also this explains why this engine doesn't pull up my 4% grade, the traction tire on the 3rd driver set is not able to grip the rail.
I also discovered that my engine is not even balaned on the 4 wheels of the 1st and last driver sets. It wobbles when rocked by hand, and visually I can see 1 wheel rock.
The other problem was a clicking sound. There is a pin behind the sliding piston assembly (I need to learn the names of these parts) that sticks out a "bit" too far and will sometime hit the siderod of the lead driver. This might be the "thump" that others hear.
While I don't like what I found, at least now I know the problem. I think this one has to go back to Bachman, as I don't have a mill to fix the frame, nor am I good enough for the fine machining needed to fix the wheel contact problem.
Ah the limitations of N scale, and not being able to spring each driver wheel.
Gary