# Automatic Cylinder Drain Cocks.



## Tony Bird

Hi,

I own a Dixie which is a very simple 5" gauge locomotive made by a company named Maxitrack in 1984.  It is a very simple model which among other things doesn't have drain cocks but instead a valve that directs the exhaust downwards when it starts.  This is only partially effective as a lot of condensed steam still comes out of the chimney.

Exhaust venting valve.   





At the end of last season the packing on Dixie's cylinders started to allow steam to pass the pistons, it had been some years since the packing had been fitted.  As the pistons had to be remove to fit new packing it was decided to fit drain cocks.

Tapping the holes drilled for the drain cocks.





I had drawing for some automatic drain cocks which I decided to try instead of fitting level operated drain cocks.  These drain cocks are very simple consisting of a ball that will allow water to vent through a hole but will seal the hole when the steam arrives.





First one fitted to a cylinder.





A static steam test was tried.  Video.





Dixie has an external steam pipe about 15" long and with no super heat has always been a 'wet' steamer so it took nearly a minute for all the drain cocks to seal.  The video was taken while the cylinder were still cold, in subsequent steaming's it took about 15 seconds for the drain cocks to seal.   Dixie has yet to be tried on the track with these new drain cocks but I see no reason that they shouldn't function as well as they have.  I am very please with their operation.

Regards Tony.


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## kvom

I have similar drain cocks. Most of the ones I've seen point outbound of the cylinders; possibly to avoid venting on the rails?


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## Tony Bird

Hi,

*I have similar drain cocks. Most of the ones I've seen point outbound of the cylinders; possibly to avoid venting on the rails? *

Sounds like a good idea but I don't know if my model club would allow it.  A lot of children visit the club and steam coming unexpectedly from the side of the engine could be considered a problem.  Now I know the drain cocks work their exhaust has been routed through the buffer beam.






Regards Tony.


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## pkastagehand

I would like a drawing of these units if someone is able and willing.  Not sure whose it is and what copyright issues if any might be involved.

Paul


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## 10K Pete

Here is a representation of one I pulled off the net some while back. Very
simple.

OK, here is the original source:

http://ibls.org/mediawiki/index.php?title=Automatic_Cylinder_Cocks

Pete


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## Tony Bird

Hi Pete,

Many thanks it saves me having to find my drawings, which I think are very similar.  The drain cocks work very well but if there is a lot of oil in the exhaust they can stick open.

Regards Tony.


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