Question about Big Boy running gear

Great Western · **Posted:** Tue May 14, 2019 8:33 pm

Some great scenes in this clip. Still a few clunks, but that is life!

https://www.youtube.com/watch?v=Kh6RP_QSq0Y

eshro · **Joined:** Tue Sep 11, 2007 7:15 pm **Posts:** 11

About the chain drive on the lubricator. According to the William Kratville book "Big Boy", the original thin rod on the lubricator was quite susceptible to fractures. The UP designed a heavier arm, but calculations showed moments of inertia of a heavier rod would cause problems with other parts. They came up with the chain drive because there was no inertia. The chain drive was installed on all big boys in the late 1940's. The book also says, as far as known, these were the only chain driven lubricators applied to American steam locomotives. The chains were purchased in Denver, and the Cheyenne shops fabricated the sprockets and mountings.

Old Smokey · **Joined:** Sun Oct 15, 2017 7:58 pm **Posts:** 172

This is a very interesting thread.
Further to the problems with the rod-drive systems....

Here's some shots of BCR 3716, showing how it used a rod-drive to the lubricator.
This time, driven off the cross-head.
BC Rail also had problems with the rod system.
In fact the gentleman in the photo once had a breezy ride home, riding on the running boards, after the rod broke during a major fan-trip. He got to reach down, grab the broken rod end, and operate the lubricator by hand, as they headed slowly home.
Either that, or leave hundreds of passengers, stranded in the middle of nowhere.
Never mind blocking the main..

PMC · **Joined:** Sat Oct 17, 2015 5:55 pm **Posts:** 2876

I guess they put 4014 on the ground in the yard at Rawlins WY:

http://trn.trains.com/news/news-wire/20 ... derailment

No damage apparently.

Kelly Anderson · **Joined:** Tue Sep 14, 2004 7:52 am **Posts:** 2477

bbunge · **Posted:** Sun May 19, 2019 11:20 pm

Kelly Anderson wrote:

Sperry cars aren't the only game in town for finding track defects...

Of course it can happen to anybody.
Guess he wasn't watching where he was going.

Well, very clearly, he was looking to his right! Was there a girl over there or something?