Newsgroups: rec.pyrotechnics
From: John De Armond
Subject: Re: Thermite Lance
Date: Mon, 01 Nov 93 00:00:59 GMT

farb@ecr.mu.oz.au (William_Cuming FARROW) writes:

>I was wondering if anyone has heard of, or knows how to build, 
>a thermite lance. It is aparantly a tube with a hole at the bottom,
>and you pour or blow thermite through it, igniting it a the bottom.
>Forming a Lance, or jet that can cut steal, a bit like an oxy torch.

You're referring to something commonly called the thermic lance.
Nothing to do with thermite.  The one I used to sell in my welding
supply shop was a steel tube about an inch in diameter stuffed with
a sheet of rolled up steel so that air could flow around it.  In use,
it was connected to an oxygen manifold and ignited by shorting across
a car battery, touching with a welding electrode or something similar.
The extremely hot iron-oxygen reaction would gouge just about anything
including concrete.

These things are not subtle.  The operator normally wears a heat-proof
suit similar to what firemen use.  Special heat-resistant head and eye 
protection is necessary.  IT is really only suitable for demolition.

John

From: khays@sequent.com (Kirk Hays)
Newsgroups: rec.crafts.metalworking
Subject: Re: CUT ANY MATERIAL LIKE BUTTER
Date: 27 Feb 1997 15:43:24 GMT

In article <5f2753$l9i@bobcat.ent.ohiou.edu>,
Mark Kinsler <kinsler@bobcat.ent.ohiou.edu> wrote:

>That's what I was trying to think of.  What exactly is a thermic lance?  I
>visualize an iron pipe filled with thermite or something, fed with an
>oxygen hose from the cool end.  It sure isn't cold fusion (these guys have
>to be Russian) but from what I've read about the devices, the capabilities
>haven't been overly exaggerated.  Apparently they can cut just about
>anything, consuming themselves in the process. 

Correct.

When I was in Highschool, a bunch of us decided to build one of these.
We wound up doing it several times, due to the extreme Fun Factor.

Basicly, we got a 10 foot piece of black iron pipe (no galvanizing,
no zinc fumes, eh?), and plumbed it to a tank of oxygen from Dad's
welding rig.

Getting it lit is the trick - we used magnesium shavings packed around the
business end of the pipe (a sometimes thing), or thermite (the preferred
method).

Once it is lit, the iron pipe begins to burn in the pure oxygen 
coming from inside the pipe.  White hot flame, and lots of it, with
accompanying roar.

We used it to burn through:

	several automobile engine blocks (too easy)
	a three foot chunk of reinforced concrete (moderately difficult)
	a large granite boulder (hard, had problems with crud in the hole)

Wear insulating gloves to hold the pipe, and welders goggles are de
riguer.

Don't plan on using the last three feet of the pipe, as the action
gets pretty intense that close to the burn.

You can, of course, make the pipe longer before you start.

Keep someone ready to turn off the oxygen, as this is the only control
you have - you can't "snuff" the flame, and it will continue to burn
underwater.

The hole size you cut is very dependent on the material you are
cutting, and is very ragged.

Molten iron splatters will coat everything near the hole.  Small fires
will start if you're careless.

This technique has been used (and probably still is) to "crack" safes.
I've seen films of divers using this to cut up shipwrecks, too.

Kids, don't try this at home.  Do it out in a gravel pit, instead.

I'm betting the folks over in rec.pyrotechnics can give some insight,
too.

--
Kirk Hays
[I don't speak for Sequent.]