Wikipedia:Featured picture candidates/Steam Locomotive

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[edit] Steam Locomotive

The main moving parts of a steam locomotive with Walschaerts valve gear: 1 - Link, 2 - Eccentric crank, 3 - Radius rod, 4 - Lap/lead lever, 5 - Crosshead, 6 - Valve, 7 - Cylinder, 8 - Reach rod

A detailed animation of the exterior working parts of a steam locomotive. This animation is from the commons, and is already a featured picture there..

• Nominate and Support TomStar81 03:30, 14 April 2006 (UTC)
• Support. Nice, clean, and very instructive and apparently wrong, so Oppose from me (Dschwen 10:47, 17 April 2006 (UTC)). --Dschwen 07:45, 14 April 2006 (UTC)
• Support. This one really deserves to be a FP. Encylcopedic and clean. Mikeo 08:27, 14 April 2006 (UTC)
• Support. I'm still a little fuzzy on size requirements, but this a quite nice animation. Changed to Oppose per discussion below. Mooveeguy 19:38, 20 April 2006 (UTC) Mooveeguy 14:33, 14 April 2006 (UTC)
• Weak oppose There is one main problem I have with this diagram, and that is that it does not expain where the force is coming from to move the train. Either, there needs to be a better caption, explaining how the engine is doing what it is doing, or the diagram needs to be improved to include it. At the moment, it looks as if the wheels are making the engine move, when it should be the other way around. Maybe a good explanation of what is going on at 6 and 7, and what the small black arrow at the top is. --liquidGhoul 15:17, 14 April 2006 (UTC)
• Support Good pic, needs a good text explanation to go with it though. -Ravedave 05:08, 15 April 2006 (UTC)
• Support Not a diagram of a steam engine but rather of a locomotive -- doesn't really need to explicitly show that the engine provides the force. Excellent illustration of the mechanical aspects outside of the engine. BryanHolland 20:24, 15 April 2006 (UTC)
• Strong oppose because of a technical error I myself added this pic to the locomotive article, but I don't support it for FP because of an error: The lap and lead lever should not have a swinging support link above it (this would cause a twisting force to the valve stem). Also, there's a better image here: Walschaerts_valve_gear. Please consider nominating that one instead. --Janke | Talk 16:33, 16 April 2006 (UTC)
• Oppose. I don't understand the engineering, but Janke convinced me. Stephen Turner (Talk) 21:16, 16 April 2006 (UTC)

More info: I've studied hundreds of pictures of steam loco valve gears, but I've never seen one with a support like that - the stem is always supported by a sliding crosshead, not a rocking lever. (Also, I've built this 1:8 scale model, which has the same Walschaerts motion.) There's actually another error, too: The bell crank at the end of the reach rod is not at the right ange - it would interfere with the link when the engine is set to reverse. Also, this animation shows avery uncommon form of outside admission piston valve - usually, they are all inside admission. <rant mode off> ;-) --Janke | Talk 21:34, 16 April 2006 (UTC)

• • I was unaware of the error in the picture; If I had that it was not factually acurrate I probably would not have nominated it here. In light of this sudden development, which of the images from the Walschaerts_valve_gear article would you recomend for consideration as an fpc? TomStar81 00:17, 17 April 2006 (UTC)
    • I'd say this one (too large to show below the nominated one), my only gripes are that it has a very conspicious creator signature, and that the bell crank is positioned a bit awkwardly behind the link - it may be an exact depiction of some loco, but it's less clear. To compare, here's the 1914 drawing I used when building my own loco model... --Janke | Talk 09:17, 17 April 2006 (UTC)
  • I think I like you version better than I like the current one, so if it is possible to vote for that one instead of the current one I think we should do that. (Also, yours is factually acurate ;) TomStar81 09:56, 17 April 2006 (UTC)

• • • It's not "my" version, it's just one that I found while perusing WP. But here it is (unfortunately, it can't be scaled down nicely...) Yes, I'd support this one. Can we do something about that signature? --Janke | Talk 11:04, 17 April 2006 (UTC)
  • Comment. Should we start again with a new nomination for this image? It's not just an edit to the old one, so it seems to me that the above votes aren't really relevant any more. Stephen Turner (Talk) 18:03, 17 April 2006 (UTC)

I nominated it above. --Janke | Talk 10:52, 18 April 2006 (UTC)

Not promoted Mikeo 23:39, 21 April 2006 (UTC)