Boiler check valves

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Berkman
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Joined: Wed Aug 16, 2017 7:55 pm

Re: Boiler check valves

Post by Berkman »

What's the pricing on the ex Mercer checks and safeties?

thanks!
Soot n' Cinders
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Joined: Wed Jun 27, 2012 5:24 pm
Location: Marietta, Georgia

Re: Boiler check valves

Post by Soot n' Cinders »

I use PM Research valves. My arrangement is an elbow coming out of the boiler, then into a straight globe valve, and then into a straight check valve. They make great valves, but my setup is more typical of a logging locomotive than a mainline locomotive.
-Tristan

Projects
-2.5" scale Class A 20 Ton Shay

Steam Siphon: https://www.shapeways.com/shops/leavitt ... tive-works
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NP5002
Posts: 42
Joined: Sun Dec 30, 2012 10:02 am
Location: Redmond, Oregon

Re: Boiler check valves

Post by NP5002 »

Ask Dave with super scale. I received 2 Hancock check valves from him about 3 months ago. Just gotta ask him.
Dave Workman
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JBodenmann
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Joined: Sun Oct 26, 2003 1:37 pm
Location: Tehachapi, California

Re: Boiler check valves

Post by JBodenmann »

Hello My Friends
Here are a couple check valves you might like. These are very easy to machine as they have an O ring on a poppet. This design has a couple advantages. The O ring being flexible allows it to seat on a imperfectly machined surface. So machining of the valve is easy. I use a brand new two flute end mill to machine the seat as on valve #2. It is also very forgiving of contamination in the feed water, unlike a valve with a metallic poppet or ball. Check valve #1 uses a ball for the body and is 2-1/2" scale but the body can be whatever you want, a ball or cylinder like valve #2. The poppet is the same for both valves. The valve can be made of free machining brass or bronze, whatever you have laying around. I have made many over the years and they work great.
Happy Modelbuilding
Jack
Attachments
Check Valve1.jpeg
Check Valve2.jpeg
Berkman
Posts: 679
Joined: Wed Aug 16, 2017 7:55 pm

Re: Boiler check valves

Post by Berkman »

how often do the o rings need to be replaced on an O ring check ?
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JBodenmann
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Location: Tehachapi, California

Re: Boiler check valves

Post by JBodenmann »

Hello My Friends
The O rings usually last three or four years.
Jack
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NP317
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Location: Northern Oregon, USA

Re: Boiler check valves

Post by NP317 »

Barry of SuperScale made check valves with metal-on-metal seats.
Over the years of use I have had to periodically re-grind in the seats to stop leaks. Prototypical.

Dave S of Mercer Works made his check valves with o-ring sealing seats.
So far I've never had to service any seats, and they seem a better idea to me for our model usage.

Just my take on the subject.
RussN
amadlinger
Posts: 174
Joined: Sat Jun 23, 2007 8:18 pm
Location: Central NJ

Re: Boiler check valves

Post by amadlinger »

Hi Russ,

I'm curious as to your procedure for refacing the SuperScale check valve poppets. I recently used the "Timesaver" non-imbedding lapping compound (specifically made for soft metals) to lap the poppet in mine after several years of use.

Sincerely,
Adam
Berkman
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Joined: Wed Aug 16, 2017 7:55 pm

Re: Boiler check valves

Post by Berkman »

As long as the valves are easy to take apart/access and the O rings are standard easy to find size, I'd much either have to replace a few O rings than re lap a valve seat
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NP317
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Location: Northern Oregon, USA

Re: Boiler check valves

Post by NP317 »

Berkman wrote: Wed May 19, 2021 12:21 pm As long as the valves are easy to take apart/access and the O rings are standard easy to find size, I'd much either have to replace a few O rings than re lap a valve seat
My point exactly.

And I have also used Timesaver for lapping in valve surfaces that are lightly scored. And will do so again when needed.
RussN
FKreider
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Joined: Fri Feb 02, 2018 8:44 pm
Location: Massachusetts

Re: Boiler check valves

Post by FKreider »

jeanluc83 wrote: Tue May 18, 2021 8:55 am Can someone share drawings for an easy to build reliable check valve for general use in 1-1/2 scale? I’ve found many different variations in all different sizes but it’s hard to find feedback from people who have actually built them.
Probably because they just work.... not much to talk about. They are very simple devices.
-Frank K.
Berkman
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Joined: Wed Aug 16, 2017 7:55 pm

Re: Boiler check valves

Post by Berkman »

Going back to the original question, just buy a PM research globe check for like $30 and be done with it, they will be super reliable, look nice, and ultimately pretty cheap. I would 100% put a valve between the check and boiler, that way if you need to service the valve under steam or it has an issue you can just shut it off.
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