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TheFrenchCanadian
06-22-2004, 09:37 PM
Hi guys,

Here's the deal; I was back home (Winnipeg, Manitoba...)with my daughter at Easter (gave my wife a break...), and my dad gave me a set of owned tanks he had kicking around (40 cu. ft. Acetylene and similar sized oxygen).

They happened to be Air Liquide tanks, so I took 'em there to get filled (actually traded 'em for a filled set, to be accurate). Tonight I finally get around to doing a little O/A welding (finally...), and what the he**, my Acetylene regulator doesn't fit!! Oxy is fine, but the threads on the Acet. valve appear to be about 18 tpi while the reg (which has some kind of adapter on it... see photos...) looks to be about a 14 tpi. WTF?? Anyone heard of this?? Obviously I need some kind of adapter here I guess, but that is news to me...

What's the deal??

Photos below....

First the tank...

TheFrenchCanadian
06-22-2004, 09:38 PM
Close up of the threads on the tank...

TheFrenchCanadian
06-22-2004, 09:38 PM
My regulator w/adapter...

TheFrenchCanadian
06-22-2004, 09:43 PM
Forgot to mention, threaded nut on regulator has "CGA - 510" stamped around the neck of it. Also, it will thread onto a standard propane tank valve.

Guess I'll be making an unschedualed trip to the welding supplier's tomorrow... but what the heck do I ask for :confused:

And finally regulator and adapter threads close up...

Franz
06-22-2004, 10:54 PM
There are no fewer than 5 different tank threads for acetelene here, depending on the distributor.
Your regulator is a fairly normal thread, and you just need to buy an adaptor tothe acet cylinder you have.

TheFrenchCanadian
06-23-2004, 12:53 AM
Well, well, who'd a thunk? :) To be honest, I guess I never gave it much thought before! I just assumed that someone at one time had decided on a way to do it and everyone just stuck to it. I should know better than to assume that we, as humans, might do something the easy way when we can make it so much more complicated and entertaining!! :D

Thanks Franz!
Luc

TheFrenchCanadian
06-23-2004, 03:38 PM
Went to the supplier and he knew all about it. Apparently Air Liquide uses CGA-410 male (RH) threads on their tanks, and my regulator is a CGA-510 male (LH) thread. So I need a CGA-410 (RH) female to CGA-510 (LH) female connector (complicated eh?). I ordered it and it should come in tomorrow... Apparently this is a Canadian thing, according to some stuff I read on the 'net. is that true? You guys in the 'States ever run into this before?

Whew, what a bunch of B.S. just to get my regulator onto my Acetylene tank! :)

Luc

Markopolo
06-23-2004, 07:33 PM
French C. If it makes you feel any better....I dated a girl from Montreal (Laval-Ouest), and SHE'S rather "complicated" also :D

Paychk
06-23-2004, 08:51 PM
Here in the states, all acetylene connections are left hand thread. When I looked at the second pic and saw the right hand threads, I thought someone had screwed up big time, until your post about Canada and right hand threads.

TheFrenchCanadian
06-24-2004, 01:14 PM
Update:

Supplier said he knew all about it but when I went to Acklands Grainger this morning to pic up the adapter - I took one look at it and knew it wasn't right. The adapter he ordered had LH thread on both ends and the tank end threads seemed just as coarse as the CGA 510 threads - not good. :mad:

He kept insisting over and over that that's what the book said I needed and the book had to be right - so I said thanks but no thanks and went to Air Liquide and got screwed to the tune of $35 Cdn for the right adapter. :(

Anyway to make a long story longer... turns out to get from a "B" tank to a CGA 510 reg you need a CGA 520 to CGA 510 female to female adapter (in Canada, anyway...). I guess CGA 520 is RH thread by definition...

Had I know exactly what I needed to start with I might have been able to phone around and find it for cheaper, but oh well, it cost me a few bucks & I (and a few others probably, too!!) learned something, which is always a good thing... :rolleyes:

At least my Dad was nice enough to give me the tanks for free! :D

Pic of the adapter in question for future reference...

SDean
06-26-2004, 02:54 PM
Many years ago (IIRC 1910s)the two smallest Acetylene cylinders were used to fuel headlamps on cars/trucks and motorcycles. After the battery powered lights showed up these cylinders drifted into use by plumber/craftsmen for use on air acetylene torch setups. The littlest one is called an MC for motorcycle and the B size is for Bus. They used to have a pressure guage on the bottom and the B's valve was offset to one side so it could be used horizontally. If you find one thats still got a good coating of chrome and the instructions printed on it, it is worth something to collector. (although the one with guages have been pulled from service)

Shade Tree Welder
06-26-2004, 03:34 PM
Many years ago (IIRC 1910s)the two smallest Acetylene cylinders were used to fuel headlamps on cars/trucks and motorcycles. After the battery powered lights showed up these cylinders drifted into use by plumber/craftsmen for use on air acetylene torch setups. The littlest one is called an MC for motorcycle and the B size is for Bus. They used to have a pressure guage on the bottom and the B's valve was offset to one side so it could be used horizontally. If you find one thats still got a good coating of chrome and the instructions printed on it, it is worth something to collector. (although the one with guages have been pulled from service)

And the company that developed and patented the designs was .....Prest-o-lite. They developed the DE/acetone tank.

SDean
06-26-2004, 04:03 PM
And the company that developed and patented the designs was .....Prest-o-lite.


Yup! And the CGA-510 for years was called the P.O.L. Valve (Prest-O-Lite) Verses the Airco CGA-300. That's why we had (and still have some) so many acetylene valve threads. Linde (Prest-O-Lite) and Airco battling it out for world dominance. :-) Ah, those were the days!

Franz
06-26-2004, 10:58 PM
Whoa there Nelly, "B stands for Bus" I don't know where that comes from, and it don't make a lot of sense cause by the time busses came along, they had electric headlights.
Damn, I'm old enough to remember POL tanks with gagues, and I still own a few with the plug in the bottom, but none of em are chromed.
I even have one of the old torches that operated with a needle valve at the tank, and the torch for detecting Freon leaks.

DDA52
06-26-2004, 11:20 PM
Here in the states, all acetylene connections are left hand thread. When I looked at the second pic and saw the right hand threads, I thought someone had screwed up big time, until your post about Canada and right hand threads.

Paychk
I used to think the same thing. HOWEVER, I ran into the same problem when I moved to N. Va./ Wash DC area. I had all left threads as nature intended on my acet regs. The bottles that I rented from Roberts Oxygen were all right. They said that all their bottles ( acet ) were this way. I had never heard of such a thing. Twenty bucks later, I was up and running.

Paychk
06-27-2004, 12:47 AM
Learn something new every day......THANKS! :)

SDean
06-27-2004, 12:57 PM
Whoa there Nelly, "B stands for Bus" I don't know where that comes from,
Well that is what I was taught (by a guy way older than me) back in the 60's. I never understood it either. I have seen the "B" mounted on the running board of some of the older touring cars at the Harrah's Car Musuem in Reno. (they also have an old motorcycle with an "mc" too). Maybe someone else knows the story of the "B".