O/A Torch Question

[Cap-n-Cray]

Dan, check valves are a good idea. I forgot I have them on mine both sides. Installed them when I first hooked up the regulators. Don't even think about them.

Cary

 

[BrentD]

I stopped by the local lumber yard at lunch and looked at the O/A kits they have there and noticed something fundamentally different on my torch.

All the kits I saw had torch bodies made like the diagram Lazy posted. The control valves immediately follow the hose connections right at the base of the torch body. My HF torch has the two control valves right at the top of the torch body about a half inch from the mixing chamber where the torch tip or cutting body attaches.

The manual for the harbor freight torch says it has built-in check valves, but they're obviously not working.

And no, the torch has never been damaged. It's been used maybe three times since I bought it, the last time maybe four or five months ago and it's been sitting by itself in the back corner of my workshop ever since. Thinking back to the first couple of times I used it, I do remember seeing that the acetylene pressure gauge rose beyond what I had set it to and the flame was a bit finicky so I had to turn down the Oxygen pressure and barely open the oxygen control valve. I guess the torch has been flawed since the time I brought it home, but I've never used it when the weather was cold like yesterday. Could be that there is an internal crack inside the torch body that mostly seals up when the torch body is warm and opens up when it's cold.

 

[Scotty370]

I don't know if I'd want to be messin' with a torch that's mixing gas in an unknown fashion, at uncontrolable pressures, for an unknown reason! Here's a copy of my late January post:

Harris Oxy/Ace Torch Set.. Kudos!!!

--------------------------------------------------------------------------------

Call it Sunday Night 'drivel', but I recently purchased a new oxy/ace torch set made by Harris. I purchased thru an E-Bay distributor/store, but you can purchase direct. Got prompt/cheap shipping, and just fired it up today! What a joy to work with quality tools. The set cost $175.00. What amazed me the most, other than it's performance today, was that the whole set was made in the USA!!! Yep, everything!! The torch handle and cutting tip I would expect, but everything that was included! Hoses, tips, regulators, right down to the spark lighter!!!! Sure nice to see we still make something! ~Scotty

(And no, I don't work for them!)

 

[Larry Jones]

I stopped by the local lumber yard at lunch and looked at the O/A kits they have there and noticed something fundamentally different on my torch.

All the kits I saw had torch bodies made like the diagram Lazy posted. The control valves immediately follow the hose connections right at the base of the torch body. My HF torch has the two control valves right at the top of the torch body about a half inch from the mixing chamber where the torch tip or cutting body attaches.

The manual for the harbor freight torch says it has built-in check valves, but they're obviously not working.

And no, the torch has never been damaged. It's been used maybe three times since I bought it, the last time maybe four or five months ago and it's been sitting by itself in the back corner of my workshop ever since. Thinking back to the first couple of times I used it, I do remember seeing that the acetylene pressure gauge rose beyond what I had set it to and the flame was a bit finicky so I had to turn down the Oxygen pressure and barely open the oxygen control valve. I guess the torch has been flawed since the time I brought it home, but I've never used it when the weather was cold like yesterday. Could be that there is an internal crack inside the torch body that mostly seals up when the torch body is warm and opens up when it's cold.

The check valves may be just a steel ball held in place by a spring, The oxygen caused them to rust away I bet. That is what happened to a SolidOx torch I picked up at a yard sale once.

 

[Baby Grand]

... but in this case where the flaw is causing the mixing of flammable gases and creating a situation that could prove extremely dangerous, I'm not going to trust my life to it. Further I feel like I should do something more than just toss the torch. This flaw is pretty serious and needs to be reported to somebody.

BrentD - You are absolutely correct - reporting it would be the right thing to do, and I'm ashamed that I didn't think of it. One hand washes the other.

Jim

 

[Mike_Kanzer]

Brent-
Two other things to keep in mind with Oxy-acetylene set-ups (though you might be aware of these already).
1) If you try to draw down an acetylene tank to zero pressure you will pull acetone up into the regulator and damage the diaphragm.
2) Never operate the Acetylene above 15psi - the gas can explode above this pressure.

From the discussion above I would agree that it seems like you have bad check valve.

Just my .02 - Mike

 

[BrentD]

Brent-
Two other things to keep in mind with Oxy-acetylene set-ups (though you might be aware of these already).
1) If you try to draw down an acetylene tank to zero pressure you will pull acetone up into the regulator and damage the diaphragm.
2) Never operate the Acetylene above 15psi - the gas can explode above this pressure.

From the discussion above I would agree that it seems like you have bad check valve.

Just my .02 - Mike

I'm aware of both of the two rules you mention above, but thanks. Never hurts to be reminded, particularly about the 15psi thing.

On the check valve thing, granted my torch either doesn't have check valves or they are not working, but if the problem was just a check valve, then it seems like I would only get the feedback after opening both the acetylene and oxygen flow control valves instead of all the time, whether the valves are opened or closed.