[TheForge] Oxy/Propane reprise

[Ben Barrett]

Yeah, its been a long month+ without his bits and bytes flowing through here
:)

I recently learned that this type of torch, which uses lower-pressure feed
and a venturi-style burner with the oxy pulling in the fuel, is known as an
"injector" type torch, IIRC, and I was wondering if any metalworking folks
have used any torches from the glassworking world; bench-mounted oxy/propane
torches for "lampwork" are very popular here on the west coast, and can be
found used pretty easily.  Most of these I've seen are *not* injector style,
however most are built for continuous use and have cooling systems built
into the torch body, and some have two torches mounted on one unit (usually
like a big rosebud, 1"-2" wide, underneath a cutting-head-sized tip).  The
bigger units require manifolding multiple 281(?) oxy tanks, and many glass
shops now run with liquid oxygen.

I'm more interested in this injector type now, particularly whether a
venturi torch made for a different medium or purpose could be useful (I just
want heat, and often a very pointed spot-heat), but also have this notion
that a small-to-mid-ranged oxygen concentrator (often called oxygen
generators) which could provide 15 or 20psi of oxygen could be used with
both the low-pressure natural gas available municipally, and/or propane.  I
know the oxygen with the natural gas would just not get as hot, but heck it
seems like with any oxygen generator why not mix some extra oxy into what
were previously only fuel-air combo's, such as the forge (when one wants to
weld, heh)...?

This is not to knock Allstate's torch!  I want one, and am just wondering if
something I might find used locally might work for the heating-only part
(again, I am not concerned with cutting for this particular question).
Cutting seems to be a well-solved problem... only if it were, in practice.
:)

Thanks much,

Ben



On Sun, Nov 15, 2009 at 3:28 PM, <williamsiron at comcast.net> wrote:

>
>
> Since Frosty is back on-line, we could ask him about oxy/propane rigs. He
> has one sold out of Idaho, All State Distributers, I think.
>
>
>
> Mark Williams
>
> Snow Hill, Maryland
> ----- Original Message -----
> From: "Paul N" <crosspein at sbcglobal.net>
> To: "Blacksmithing List Sponsored by ABANA" <theforge at mailman.qth.net>
> Sent: Sunday, November 15, 2009 5:44:05 PM GMT -05:00 US/Canada Eastern
> Subject: Re: [TheForge] Oxy/Propane reprise
>
> I uploaded a few photos to www.photoaccess.com (see bottom of message
> for details).
>
> I believe I've labelled them accurately. The "oxidizing Flame" was
> getting noisy, so I'm pretty sure that ones right.
>
> The one labelled neutral, may have been a bit toward the reducing side,
> as the cones are a bit fuzzy. (No cutting jet yet)
>
> The last one was with the cutting jet blowing. I cut back the mixture
> until the preheat cones were less fuzzy. I noticed that the preheat was
> uneven, so my tip probably needs some cleaning.
>
> The torch cut nicely at this setting.
>
> Observations:
> While running just preheat gas, things were fine. But on some cycles
> (not always), if I preheat, then cut, then backed off the cutting jet,
> I'd get some popping in the tip, even with the tip well away from the
> work. Opening the fuel valve a little more always remedied it.
>
> All connections were tight. But if you notice, I'm left handed, and I
> still hit that gas valve with the heel of my hand on occasion. I need to
> turn that handle around to get the valves away from my hand.
>
> Again, thanks for help. Feel free to educate me further. Hopefully the
> photos will help someone else.
>
> **Paul
>
>
>
> Marc Godbout wrote:
> > Thanks, Paul. I look forward to seeing the very first photographs ever
> > taken of an oxy-propane flame. You'll be breaking new ground, never
> > before attempted.
> >
> > Seriously, though, also try taking pictures without the filter.
> > Cameras have a pretty good ability to filter by themselves. With a
> > dark background, it may adjust around just the flame. Auto-focus might
> > still be a problem, but maybe a metal background near the flame would
> > work.
> >
> > --Marc
>
>