# Water glass blow down valve



## DGM (Feb 8, 2008)

Has anybody added a blow down valve to the water glass of an Accucraft Forney? Many of the British outline locos by Accucraft UK have a "water level check valve" (or "overflow valve") which seems to be helpful in filling the boiler to the right level and during raising steam. Really like that idea (though I've never seen one in action) -- why doesn't Accucraft US do this on US outline locos? I know a water level blow down valve would not necessarily help in determining fill level for the boiler but it should at least help with clearing the sight glass. Could a globe valve be added at the bottom of the water glass? (I think some people have added a similar valve at the top of the glass?)


I also read something in a post from a few years ago (2009) about a "schwinky valve" that somebody had made for the top of a water glass. Sounded interesting. Not really sure what specific parts are needed or if they are available commercially.

Also, has anybody fitted a globe valve or similar to a lubricator to "blow out" the lubricator at the end of a run? Those T-handle drain caps are miserable when hot!

Any advice is appreciated and pics are especially helpful! (I can read and generally understand a concept but pics really help me -- as a "Live Steaming For Dummies" kind of guy -- to put a concept into workable practice.)

Greg


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## Dr. J (Feb 29, 2008)

Hi, Greg 
I've only been in live steam for a couple of years, so more seasoned hands may have more sage advice. With that caveat, in mind, read on. I have 2 roundhouse engines (the forney and a SRRL #24). In order to prevent oil from being sucked back into the boiler at the end of a run, as the water vapor in the boiler turns back into water, you've got to break the vacuum somewhere. Not having a blowdown valve (at the bottom of the sight glass), the next most logical place, in my view, is to open up the displacement lubricator to atmospheric pressure. Unscrewing the cap is the simplest way to do that. I cut a slot in the cap with my dremel (being careful not to cut all the way through the brass, or to damage the 0-ring seal), so I can use a screwdriver to unscrew the cap. Other guys solder a T-handle to the top of the cap, or I've seen brass coins or other metal bits used, so the cap essentially becomes a wing nu. Much easier than using your bare fingers. 
The other way to go, if your lubricator has a drain (and mine do), is to open up the drain promptly at the end of a run. The water at the bottom will dribble out, as will any remaining oil (catch that in a gunk jar). 
Another route (wear gloves, and keep your face away) is to remove the filler cap on the boiler. 
Jim Coplan aka Dr.J


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## jfrank (Jan 2, 2008)

David Bailey made some of these for the Accucraft C21's a few years ago. I put one on mine and it works great. You could check with him about how to do it. 

http://www.djbengineering.co.uk/index0.html


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## seadawg (Jan 2, 2008)

Greg, thanks for remembering the "Schwinky" valve! I made it myself from parts I had in my bin. The hardest part was finding the oring that was smaller than the sight glass plug.










As far as the water level check valve goes, my Accucraft C-16 came with a valve in which the instructions said something like 'fill the boiler, open the valve, fire the boiler and when the water coming out turns to steam, close the valve and begin your run.' (Of course the original boiler is no longer installed in that loco as I have replaced it with a JvR C-type alcohol fired boiler.)


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## DGM (Feb 8, 2008)

Thanks to all. 

Jim, yes, I'm familiar with opening the lubricator (either top filler cap or bottom drain plug). I've heard of people opening the lubricator drain while the boiler still has a little pressure to blow out the oil/water rather than letting it slowly drip. That is what I was wanting to achieve by swapping out the screw-in drain plug with a globe valve or similar. My Forney has a t-bar handle on the filler plug, so I can use this to relieve pressure to prevent oil being sucked into the boiler. 

John, I might try contacting DJB Engineering to see if David could make me one of these valves. 

Dave O., I still like your schwinky valve! Looks pretty simple to build but my "parts box" is pretty much non-existent since I'm new to live steam. I may contact you off-list to ask about parts to buy to make this.


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