# Resource Steam locomotive wheel connecting/driving rods.

Discussion in 'Railroading' started by Bob43, Aug 27, 2016.

1. ### Bob43Model Designer Extrodinaire Cornerstone Member

Steam locomotive wheel connecting/driving rods.

Wheel train: As far as the connecting rods of the driving wheels are concerned, are the 2 sides of steam locomotives a) mirror images, or b) one side rotated 180°, or c) rotated 90° (to hinder locking)?
Or, in other words, when the main connecting rod of one side is at its lowest position, the position of the connecting rod on the other side is a) also in lowest posiotn, or b) highest position, or c) halfway between the 2?
2. ### ToninoMember

Hi Bob! I also had your doubt when approached a steam locomotive build (it is not a cardmodel but the question is the same... btw the model is still a work in progress!) and, according to various drawings and after having asked to train experts I concluded that the wheels are rotated 90° on the two sides. Now I don't remember which one is ahead and which is behind (left/right), I must find my scribbles... I'll check as soon as I'll be home again and let you know.
3. ### draccusNew Member

Hi Bob43
This is only for two sided engines steam locomotives. All wheels are the same each side but rotated horizontal by the center axle by 180* and 90* vertically. This photo will reveal Your doubt
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4. ### Bob43Model Designer Extrodinaire Cornerstone Member

Thank you both - that's solved my question. Can't imagine that it makes any difference whether one side is 90° BEFORE or AFTER the other side; the effect is the same.
5. ### ToninoMember

Yes, @draccus your images are the best explanation to this old question. Thanks for posting. This scheme is a very useful reference and I'll keep it handy when I'll put my hands on my Pacific again. The question whether the left side should be 90° forward or backward compared to the right side is probably insignificant. I don't know if different locos had different placement of right/left angles or, instead, the arrangement showed above is universal. I'll refer to this scheme anyway and I'm sure it will be fine.
6. ### Bob43Model Designer Extrodinaire Cornerstone Member

Tonino: I like your avatar. Can you tell me what tram/locomotive it is?
Bob
7. ### ToninoMember

Yes, I'm glad you asked it.... It's a nice story about an old train that we all in San Marino love very much.
I made a build thread here about the cardmodel you see in my avatar and here is the full story behind it!
Hope you can enjoy both

Bob
9. ### ToninoMember

I'm sorry Bob: the model is not available yet. As I explain in the post it was realized to celebrate the 80° anniversary of San Marino-Rimini Railway opening and the intention was to put it on the market shortly after my test build. Unfortunately the things went another way (too long to explain) and the project is now in stand-by (not really abandoned but waiting for some input from the people who commissioned it). Now I'm trying to obtain the rights to publish it by myself (it would be a shame to let it in a drawer forever) but I don't know if I will succeed... Stay tuned! If there will be good news this is the place where they will be announced.
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