Smith Little Torch Surging

I have a Smith Little Torch that I am having a problem with. Let me try and describe the problem.
I store the torch in the garage on top of my tool box. The torch is a caddy
style. 5lb propane and 20 cu ft oxygen. I move the torch from where it sits to my workbench. I open the cylinders and set the regulators for 8lbs. This is what Smith recommends for the #7 tip. I light the torch and set it for a netural flame. I can leave the torch on the stand and it will change mixture by itself. It changes to a more reducing flame. The tank gauge on the oxygen doesn't change at all. The propane high side gauge doesn't change either. The low regulated side pressure on the propane goes up by about 2-4 lbs. It lasts about 5-10 seconds. Does this sound like a bad regulator or a side effect of moving the torch(temperature difference)? The only reason I think the temperature reason is I got the same effect last night. I left the torch and caddy sit next to the workbench for 30-60 mins and came back and the torch worked flawlessly for the next 2 -3 hours. Any help would be very very appreciated!
Thanks again, RellikJM RellikJM AT Yahoo DOT Com Don't forget about my "FREE" EPROM programming ! Advice is only worth what you paid for it!
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On Fri, 22 Aug 2003 08:22:49 GMT, "RellikJM" <GO@SPAM SOMEONE ELSE.COM> wrote:>I have a Smith Little Torch that I am having a problem with. Let me try and

Sounds like you may have a regulator "sticking" a little bit. Do you completely back off the regulator knobs when you shut down the system? I personally turn off the tanks tightly, then open torch fuel valve, bleed off fuel, then back out regulator knob, then close torch fuel valve -- then open torch oxy valve, bleed off oxy, back out oxy reg valve, then close torch oxy valve. I have a set of Airco regulators and torches and have had them for well over 30 years - NO problems like you mention. Ken.
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Another thing to check is the torch valves themselves, mine will unscrew themselves, slowly, from the body, if I don't watch them. When the gland nuts, or whatever you want to call them, are tight, I don't get any change in mixture when I manipulate the torch. It's happened a couple of times. I also have a set of regular-sized regulators that really don't like running at those low pressures, I can get some variation in gas mixtures trying to run at 2-3 lbs. I usually set them to about 5-6 lbs and use the torch valves to drop to working pressures.
Stan
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snipped-for-privacy@americanisp.net (Stan Schaefer) wrote in message

It sounds to me like you're describing regulator "drift". This is just part of living with single stage regulators. Dual stage regulators give much better results in this regard.
VT
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Why would smith put single stage regulators on a kit they designed for the little torch? It seems strange that they would say use dual stage but when they build a kit it has single stage.
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RellikJM
RellikJM AT Yahoo DOT Com
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On further reflection, it wasn't Smith themselves that reccommended two-stage regulators for the Little Torch. It was a note in the Rio Grande Jewelers Supply catalog, that is where I bought the torch kit ... and the regulators.
Bob
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I could be having a "senior moment", but I recall the paper with my Little Torch said to use hydrogen for the smallest tips. I also recall that the smallest tips have a crystal (ruby ?) lined oriface.
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