Trying to build Propane filling tube

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loganc58
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Sat Mar 26, 2011 6:14 pm

Hey guys,
I have been researching and browsing this site for many hours the last week maybe trying to figure out what all is going on and receiving basic knowledge when it comes to spudding.

I normally do not like to asked to be spoon fed information, as I am the type of person that will search till I have a good understanding of it.

But what I am trying to accomplish has me kinda confused. I am trying to create a propane filling system similar to the one attached.

I notice many people use a Bernzomatic Torch head then cut it down and thread it. Would a 1" Throwaway Cylinder Adapter or THIS work for attaching the ball valve and other things to it?

Another thing, could I get by without putting a regulator on it?

And lastly, those are milton connectors that are used to attach the tube and the 'filler' together correct? Is there a specific kind that needs to be used?


I'm sorry for all the questions, but I havent really found any how-to's to make this kind of metering system.
Thanks a lot, Logan.
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clemsonguy1125
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Sat Mar 26, 2011 6:33 pm

Im no expert by any means but I think that should work but Im not 100 percent sure. And thank you for not asking to be spoon fed. You asked specific questions, spoon feeding is questions like. How do i build a piston valve??????
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DYI
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Sat Mar 26, 2011 6:36 pm

The torch heads consist of a needle valve assembly with (3/8"-24 ?) female fine threads on the top, with a brass tube threaded into the top (at the other end of this tube is a small flow restricting orifice, followed by the torch head). What you want is to detach the brass tube from the needle valve assembly. The threads are normal direction and sealed with something similar to Loktite, requiring a pipe wrench and a disproportionate amount of force for such a small thread, to loosen.

Happily these threads are the same as the ones found on a 1/4" compression fitting. All that's needed for a lasting connection to NPT threads is a 1/4" compression to pipe thread adapter and some thread locker.

A regulator is unnecessary but highly convenient and conducive to better metering accuracy. It's also possible to simply use a pressure gauge, and fill very slowly and carefully using the aforementioned needle valve for throttling.

Any type of quick connect fitting works for the connection to the meter pipe. Many of the ones you'll find at hardware stores tend to be leaky, which may or may not be a problem depending on what you're filling. Some of the higher quality versions, such as those intended for hydraulic lines, are very well sealed, but tend to cost about $40 for a 1/4" set.

The above should give you a working fuel meter. The exact adapter in your picture is something I've never seen before, and probably not very readily available.

You're better off not finding a how-to. You'll gain a much better feel for the plumbing side of things by designing it yourself.
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loganc58
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Sat Mar 26, 2011 6:57 pm

Thanks for the replies guys,

If I were to use the adaptor i linked in the first post, this attached a 1/4" Ball Valve, followed by a pressure gauge then a female quick connect fitting; then have the male fitting for it within the pvc tube like shown in the picture?
Would this work?
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mark.f
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Sat Mar 26, 2011 7:44 pm

My first fuel meter didn't use a regulator. The needle valve on the torch head is pretty low flow and I could fill accurately to my fueling pressure.

EDIT: and check the How-To forum.
loganc58
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Sat Mar 26, 2011 8:09 pm

I'm still confused on whether or not I could use this in place of the torch head?
Any body know if this would work? Thank you.
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mark.f
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Sat Mar 26, 2011 8:17 pm

That adapter goes from pipe threads to MALE throwaway threads, for things like running a torch off bulk propane, etc.

What you are looking for is a FEMALE throwaway to male pipe thread adapter. The female part will contain a gasket and pin to depress the check in the throwaway cylinder.

EDIT: like this.
loganc58
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Sat Mar 26, 2011 8:48 pm

Okay, thanks a lot mark!
I'm going to Ace tomorrow, and will look for both the torch head and also the Female adapter.
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