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Steam operated cylinder drains?

Posted: Sun Mar 04, 2018 9:58 am
by DianneB
Has anybody build the drains shown here? http://modelengineeringwebsite.com/Drain_cocks.html

Do they work well? Any "tweaks" to improve the design?

Re: Steam operated cylinder drains?

Posted: Sun Mar 04, 2018 11:02 am
by NP317
I have a commercial set like that on my Ten Wheeler, plumbed differently. They have worked perfectly for years.
I did plumb them so there is a drain plug between each set/cylinder, accessible from the outside, below each cylinder.
When finished with an operating session, I remove the plugs and blow the water out of the system with compressed air in the boiler.
~RN

Re: Steam operated cylinder drains?

Posted: Sun Mar 04, 2018 9:34 pm
by Highiron
These are the cylinder cocks that little engines has been making and selling since the 1960s I have them in stock ready to run at $100 a set of four plus shipping

Re: Steam operated cylinder drains?

Posted: Mon Mar 05, 2018 9:36 am
by Joe Tanski
what thickness (Teflon) PTFE sheet do you guys use in these cylinder cocks.I have two sets of these one on my 4-6-0 1 1/2,one set on my 1" little engine atlantic.
I have tried to use 1/32" (.0313 )thickness Teflon white and can only get 4-5 hours of use on the cylinder cocks before the Teflon
sheet deforms and two dimples form. when the steam is turned off they will not open
Thanks
Joe

Re: Steam operated cylinder drains?

Posted: Mon Mar 05, 2018 11:30 am
by NP317
Joe: I think mine use thin hard brass sheet instead of Teflon sheet.

Mike: I PM'd the Original Poster info about the cylinder cocks still listed in your catalog.
~RN

Re: Steam operated cylinder drains?

Posted: Mon Mar 05, 2018 12:23 pm
by DianneB
Unfortunately my cylinders were tapped 1/4-28 for the drains. Don't know if I want to re-tap them ......

Re: Steam operated cylinder drains?

Posted: Mon Mar 05, 2018 4:02 pm
by Harold_V
Joe Tanski wrote:
Mon Mar 05, 2018 9:36 am
what thickness (Teflon) PTFE sheet do you guys use in these cylinder cocks.I have two sets of these one on my 4-6-0 1 1/2,one set on my 1" little engine atlantic.
I have tried to use 1/32" (.0313 )thickness Teflon white and can only get 4-5 hours of use on the cylinder cocks before the Teflon
sheet deforms and two dimples form. when the steam is turned off they will not open
I can't address the proper material, but I can assure you that using Teflon is most likely not proper. It cold flows, and will do so regardless of the thickness you choose. I'm interested in hearing what does work, though. :wink:

H

Re: Steam operated cylinder drains?

Posted: Mon Mar 05, 2018 9:39 pm
by Bill Shields
I had the same problem with VIRGIN PTFE in that application, but it works like a charm with fiber filled PTFE...

Re: Steam operated cylinder drains?

Posted: Tue Mar 06, 2018 6:54 am
by DianneB
Thanks for the discussion folks; it was very informative. After careful research and deliberation I decided to overhaul and modify my existing steam-operated drains. I don't know who made them but I managed to reduce the height, re-packed the pistons so they move more freely and hopefully don't stick in the future.