Rod won't melt

Nov 19, 2006 32 Replies

For fixing copper pipes the thing to use is solder. The stuff with a few percent silver in it is a little easier to use than plain no-lead

solder (they don't sell solder with lead in it anymore for plumbing).

All copper pipes and fittings (elbows, tees, valves) need flux to dissolve the oxide layer so that the solder will stick. Go to you closest home store and buy a book on plumbing and it will likely explain all you want to know.

--Glenn Lyford

True enough..in the Spring

Rule #35 "That which does not kill you, has made a huge tactical error"

Yup, no argument with oxypropane for brazing and cutting. Acetylene is getting really expensive, too! I hook up the propane bottle and grab the big Smith torch when I have some heavy heating to do. But for small work I much prefer the precision of O/A and the Meco Midget torch. That's my "go to" torch 90% of the time. It can weld thermocouples, weld .060 aluminum sheetmetal, bend 3/4" bar and about silverbraze antlers on an ant. I like it!

A fuel gas releases the same number of BTU/lb whether burned with pure oxy or air. However, air is only about 21% oxygen, so much of the heat liberated goes into heating up the other 79% of the air in the flame before it ever gets to the workpiece.

When burning with oxygen, propane actually has about twice the heating value (BTU/cu ft) of acetylene, though acetylene has about twice the flame temperature. The big difference is flame propagation velocity: acetylene flame propagates much faster than propane, so you can have a much higher rate of flow without the torch blowing out. The result is that a given size oxyacetylene has both twice the temperature and twice the heating value of a comparably-sized oxypropane flame.

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One thing about Acetylene it requires a little more paperwork now that 9/=

11 occurred. New rules. Propane is everywhere and easy to obtain.

It might depend on the local or state rules on explosive gas rules..

Martin

Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net=

NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member

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D> >=20

1,000,000 B.T.U.)

will go bad, but

"Don Foreman" wrote: (clip) acetylene has about twice the flame temperature. (clip) ^^^^^^^^^^^^^^^^^^^ The rest of your post is so well written and accurate, I am sure you will not mind a little nit-pick. "Twice the temperature" is meaningful only if it is measured from absolute zero. I am sure acetylene does not burn at that high a temperature with respect to propane (I haven't actually looked it up.)

Ah..err..ahum..eee.....yah!! What Don said!!

Gunner

Rule #35 "That which does not kill you, has made a huge tactical error"

The actual temps are listed in the cite. Propane air 2950F, oxyacetylene 5900F. You're quite right, the absolute temp of an O/A flame is only 1.865 x as hot as propane air. How about hot and damned hot? Oxypropane burns at 5650F but not nearly as fast as acetylene. Dare I say half-fast?

In MN, the only additional paper required of the user is green.

Sounds lucky there - my brother has a small tank and he is a previous Army Tank Commander Trainer - and had to fill out security documents. Maybe the local company(chain...) requires it.

Martin

Mart> >

Bad analogy. The pool would fill at a net rate of 200 gallons an hour, or in

10 hours. Then it will stay perpetually filled to the very top and spilling 200 gallons over the edge, as long as the 500 gallon per hour water hose is supplying water.

Sounds like what we call a crack torch.

Be sure you don't have a hole in your shorts . It can get positively ugly (and painful , as my brother found out) if you do .

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