To paraphrase Vane Jones, "Knowledge is of little value until shared with others."

Wednesday, March 18, 2020

Trolley Pole Length - Another Lesson Learned

If you've been following this Blog for any length of time and have read the old Posts, you know there were some Posts which covered the subject of trolley poles before.

Something not covered before is the topic of this Post. For lack of a better way to describe it, let's call the topic "Trolley Pole Length". Most trolley modelers will take a new trolley pole out of the package, place it on the model, and run the model without any problems.

I'm working on a new model that came with 2-56 screws mounted in the roof where the trolley poles should be attached. If you obtain a completed body with the 2-56 screws  mounted for the trolley poles, always verify the location of the screws are correct. I verified the locations on my model.

The power and trail trucks were mounted on the model at the truck centers as indicated in records of the prototype cars. I know the trucks are mounted in their correct positions. This is mentioned as the location of the truck centers will effect the performance of the model, for example, body overhang on curves, trolley pole(s) following the wire at trolley wire frogs, and more.

The model being worked on came with trolley poles so those are the poles which will be used. One of the poles was attached, the  car placed on the track near a turnout, trolley pole placed on the wire, and the model pushed by hand through the turnout. As the model went through the turnout taking the diverging route, the trolley wheel came off the wire before reaching the trolley frog.

The model was tried a few times more with the exact same result. Most of my models have no problem with the trolley pole going through the frog at this point. The 2-56 screw for the trolley base is in the correct location. Therefore, something has to be wrong with the trolley pole being used.

Next to where the new model with trolley pole was tested was an older model whose trolley pole worked correctly through the turnout. This trolley pole was removed from the older model and tried on the new model. It worked every time the model was pushed through the divergent route of the turnout.

A side by side, trolley pole base to trolley pole base, comparison between the trolley pole that didn't work vs. the trolley pole that worked was made. The over all length of the new trolley pole that didn't work was 1/8" (6 scale inches) longer than the trolley polled that worked.
The body of the trolley wheel casting on the left is longer than the casting on the right. 

Further inspection showed the body of the brass wheel casting wheel was longer. This meant the wheel casting had to be unsoldered, the wire used for the shaft of the pole cut short by 1/8", and the casting re-attached.

After the trolley poles to be used with the new model were shortened, the model was tested again going through the turnout. Everything worked correctly.

In the words of the great Trolley Philosopher, "Not all trolley poles are created equally!"

Cheers,
Ed