Silly snowbound newbie air compressor question

ozarkcat · #1 2011-02-02, 5:54pm

So, I've been stuck the past two days, snowbound, and dying to use my new torch (National 8M, SM7 tip). I've got everything for the propane side - regulator, hose, flashback arrestor, etc., but am waiting for my oxycon (no real delay, just standard waiting on shipment).

I've got an air compressor, 18 gallon, capable of running an air nailer, drills, etc. for hours on end with no problem. It's basically got an on-board regulator that tells the pressure in the tank & the pressure in the line. I'm pretty sure I can get it down far enough for the oxygen side of the torch, and DH mentioned the possible issue of burning nitrogen because it's not straight oxygen - I didn't figure that would be any worse than working with a hothead.

So, has anyone tried this before or can they think of any real problems? If no one can think of anything by tomorrow afternoon, I'll try to steal a bit of studio time with some cheap glass & report back the results . . . . .

squid · #2 2011-02-02, 5:55pm

Sorry - won't work. It has to be at least about 90% oxy.

laserglass · #3 2011-02-03, 5:01am

if you buy a PA-1 adapter, and a N style tip, you can use your torch with an air compressor and it will not require any oxygen.

http://nationaltorch.com/tips.html

squid · #4 2011-02-03, 8:49am

But won't it have a very reducing flame?

ozarkcat · #5 2011-02-03, 9:16am

I can't imagine it'll be any worse that a Hothead would be, since it would be working the same way. Plus since the air would be under pressure instead of just being pulled from atmospheric, I would think it would burn a little hotter than that. My main concern was the safety end of things.

Dale M. · #6 2011-02-03, 9:54am

Your 8M with "compressed air" tip (N series) will burn at about 3800° f. about same temperature as Hothead, only real difference is going to be flame size/body.....

Propane with oxygen burns at about 5300°f., that is pretty big "give away"...

Its pretty much the physics/chemistry of combustion and not as much torch type...

Dale

ozarkcat · #7 2011-02-03, 10:01am

That's good to know. I'm mainly battling the "I haven't been able to play with the new torch yet and I'm going really nuts with cabin fever" bug at the moment

but wanted to make sure I wasn't fixing to do something really stupid since I hadn't worked with a fuel/O2 torch before. I really appreciate all the help on here!

Mark, thanks for the info on the air/fuel tips - I'll have to look at those as an option for down the road!

Dale M. · #8 2011-02-03, 11:53am

IF its driving you that crazy... Get a snow plow and make your way out to nearest welding/gas supplier and get regulator and oxy tank....

It would be money better spend than on fuel/air tips that once you burn oxygen you will probably never go back to....

Dale

laserglass · #9 2011-02-04, 5:40am

Quote:

Originally Posted by squid

But won't it have a very reducing flame?

a hothead torch is reducing because the venturi cannot suck enough air into the flame using the flow induced by the propane jet exiting the oriffice. when you have a compressor, you can adjust the flame chemistry to neutral. you won't be able to work boro on a fuel/air torch, but you can easily work any soft glass. most glassblowing furnaces use fuel/air torches. i am not aware of any that use pure oxygen. NONE.

squid · #10 2011-02-04, 1:17pm

Quote:

Originally Posted by laserglass

a hothead torch is reducing because the venturi cannot suck enough air into the flame using the flow induced by the propane jet exiting the oriffice. when you have a compressor, you can adjust the flame chemistry to neutral. you won't be able to work boro on a fuel/air torch, but you can easily work any soft glass. most glassblowing furnaces use fuel/air torches. i am not aware of any that use pure oxygen. NONE.

Great info - thanks!