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  • Topic: B'mn Shay; auto (floating) valve gear reverse?

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    • January 9, 2019 10:15 PM EST

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      B'mn Shay; auto (floating) valve gear reverse?

      On Schreyer's nice website for Shay tips, he describes a Dave Goodson method for making the Bachmann Shay, "reverse," it's valve gear upon each change of direction.  Involves removing the cab link and getting all the valve ear working really free and easy.  >>Anyone ever accomplish this here????<<<    I'm rebuilding an early version Shay and have the cylinders out.  (Which didn't go at all as some information suggests)  Anyway, I'm reading Schreyer and just got my valve gear all working well.  (Couple hours tuning THAT up)  

      Anyone get this trick working?  And how do you like it?  Actually, "flip," each time engine reverses direction?

      Cheers, Dennis

    • January 12, 2019 2:00 PM EST

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      Ahhhhh.  So no one's tried this?

    • January 12, 2019 5:10 PM EST
      • Candlewood Valley, Connecticut
         
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      When I rebuilt mine I spent a little time trying to make this work, but didn't have success so I moved on.

      ____________________________________

      www.cvsry.com www.cvsry.com

    • January 12, 2019 6:53 PM EST
      • Pittsburgh, Pennsylvania
         
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      I figure, with the locomotive 10 feet from the viewer, and moving, only I would notice this, so it wasn't worth the effort for me.

      ____________________________________

      Shannon car Shops
      Home of the infamous leg lamp

      I.A.R.R.R. Member #12

      and King Butt Modeler

    • January 12, 2019 8:50 PM EST
      • Carlsbad, CA
         
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      Clearly TOC and George did it!

      ____________________________________

      Be sure­ to visit ­my site, l­ots of tec­hnical tip­s and modi­fications,­ and you c­an search ­for topics­ and key w­ords.


      ­Click HERE for Greg­'s web sit­e
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    • January 13, 2019 12:46 PM EST

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      Well, I have the valve gear working freely and easily.  Took a while to, "tune it up."  I still cannot envision how it can reverse all by itself when the loco changes direction of travel.  My only guess is still torque.  And the only way I'll find out is to finish my Shay rebuild and see what happens.  And that's exactly what I'm going to do.  If it doesn't work, nothing is hurt by trying.  I DO like seeing the valve motion now have the capability of moving properly.  I checked 2 other Shays and both their valve gear act, "stuck."  Mine did too, at first.  

      Like Greg said, "Clearly TOC and George did it!"  I guess they could answer all this.

    • January 13, 2019 7:29 PM EST
      • Carlsbad, CA
         
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      Yes, the drag left in the system provides the torque to reverse the mechanism when the direction is reversed. That's why you have to go the distance to loosen all that stuff up to be very free.

       

      Greg

      ____________________________________

      Be sure­ to visit ­my site, l­ots of tec­hnical tip­s and modi­fications,­ and you c­an search ­for topics­ and key w­ords.


      ­Click HERE for Greg­'s web sit­e
      PLEASE NOT­E: Please do NOT use private messaging, i­f you have­ a questio­n, feel fr­ee to emai­l me priva­tely, u­se regular­ email onl­y: greg@el­massian.co­m

    • February 5, 2019 1:10 AM EST

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      Update:  I spent at least 2 hours sitting comfortably with the cylinder set in my hands working the valve gear to be as free moving as possible.  There was movement interference in one place where part of one linkage rubbed against one of the plastic tabs used to mount the cylinders.  (Where one of the two screws go)  I filed clearance there.  I finally got about 90% full, free movement of the gear.

      I've now test run the Shay and I will say that it does, "reverse," often.  Not to the full travel it could, but very noticeable.  On-line instructions for this said to cut off the rod that goes up into the cab floor.  I could not bring myself to do this, but did simply enlarged the cab floor hole to give the rod lots of free movement.  Works fine;  don't have to remove it. 

      I'm pleased with having taken the time to do all this.  I must say it is not exactly, "time-efficient," but a lot of what we do is no different.  I checked another new condition Shay I have here and the valve gear will barely move at all here on it's display track.  Not so with the other;  moves freely any time.  I like this much better.  Thank you all for the tips.  Dennis

    • February 5, 2019 1:59 PM EST
      • Carlsbad, CA
         
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      Most people who have done it have responded it was worth the time, in adding additional "eye candy" to the "monkey motion".

       

      Greg

      ____________________________________

      Be sure­ to visit ­my site, l­ots of tec­hnical tip­s and modi­fications,­ and you c­an search ­for topics­ and key w­ords.


      ­Click HERE for Greg­'s web sit­e
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    • February 5, 2019 6:36 PM EST
      • Defending the State of Exile! ,
         
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      Monkey Motion ?

    • February 5, 2019 8:26 PM EST
      • Carlsbad, CA
         
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      I've heard all the movement of the rod gear, eccentrics, called "monkey motion". I just looked it up, interesting:

       

      https://books.google.com/books?id=oXMWAAAAYAAJ&pg=PA848&lpg=PA848&dq=monkey+motion+steam+engine&source=bl&ots=6pdSMKfvvo&sig=ACfU3U3gvMXOF4PaSUrDnB5gfchVmcPxXA&hl=en&sa=X&ved=2ahUKEwiVquqo-aXgAhVCy1QKHSrfBS0Q6AEwEHoECAcQAQ#v=onepage&q=monkey%20motion%20steam%20engine&f=false

       

      page 848 if the browser does not take you to the exact place.

       

      Greg

       

      (sorry, I know you wanted it to be "Rooster motion", but it might be similar )

       

       

       

      This post was edited by Greg Elmassian at February 6, 2019 7:35 AM EST
      ____________________________________

      Be sure­ to visit ­my site, l­ots of tec­hnical tip­s and modi­fications,­ and you c­an search ­for topics­ and key w­ords.


      ­Click HERE for Greg­'s web sit­e
      PLEASE NOT­E: Please do NOT use private messaging, i­f you have­ a questio­n, feel fr­ee to emai­l me priva­tely, u­se regular­ email onl­y: greg@el­massian.co­m

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