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nbk2000
December 13th, 2006, 03:44 AM
Spectre Enterprises, Inc. (Florida), seems to be the main manufacturer of these devices.

In their Contact Us (http://www.spectreenterprises.net/contactUs.asp), the names listed are Tim Mohler, Chuck Mohler, and Dr. Johnathan Mohler. Obviously this is a family owned business.

Jonathan Mohler previously worked for Monsanto as a defense contractor, and several of his patents are assigned to the US Government, having stemmed from DoD funded research.

US4963203 High- and low-temperature-stable thermite composition for producing high-pressure, high-velocity gases

US6183569 Cutting torch and associated methods

US6805832 Thermite torch cutting nozzle

http://www.spectreenterprises.net/images/largeScale.jpg

Battelle University (DoD research contractor) has a pending patent application, 20060266204, for Linear Thermite Charges.

Figure 1D in the application shows the effects of a multi-nozzle thermite torch on a steel target. This is exactly the same as that shown in the attached picture called 'Thermite-Cut.jpg', which I got from a 9/11 conspiracy article.

In the drawings, Page 10 of 13, is a design for a linear thermite cutter that looks very improvisable. :)

I'm envisioning an aluminum conduit or magnesium bike frame tube, that has a slit cut along the length of it, and packed with thermite while being clamped in a block form to keep it from spreading open under the pressure, and a small strip of removable material being used to maintain the gap during loading.

Once the thermite is loaded, the tube is removed from the form, a length of nichrome wrapped Thermalite (http://www.pyrotechniques.org/dwilliams/thermalite/thermalite.html) laid in the gap the whole length of the charge, and held in place with a strip of cellophane tape.

Once the charge is made, a wax wedge to form the jet nozzle is attached to it, in line with the gap, and the whole assembly placed in a section of steel box channel that has had one side removed, and bracing brackets already attached.

The charge and wax form are aligned in the channel, and either plaster or some other castable refractory material is poured into the channel, encasing the charge.

After letting it dry for a few days at room temperature, a slow heating in the oven overnight to remove the wax and completely dry the refractory is all that's needed to finalize the charge.

It's important that the thermite be lit along its entire length at the same time, so it develops maximum pressure. If it was to end-burn, it wouldn't develop the necessary pressure to develop the jet cutting action that makes it so efficient in this configuration.

Addition of oxygen generating materials in excess of that needed by the thermite reaction increases cutting efficiency, as the excess oxygen reacts with the superheated target material and generates additional heat, much like an exothermic torch does.

Bert
December 13th, 2006, 10:48 AM
Pyronol torch composition sounds like a candidate. Aluminum/Iron oxide thermite with the addition of Nickel and Teflon- The Teflon serves as both propellant gas generator and additional oxidizer while the Nickel alloys with the Iron in an exothermic process. US Patent 537069 http://tinyurl.com/y9orz9
(edit)
Upon reading the patents, the Teflon composition is mentioned.

sparkchaser
December 14th, 2006, 02:46 AM
Sounds like a bit of a redundancy when shaped cutting charges are already common. I suppose there could be a few special purposes that it might be more efficient at though. Sort of a niche demo item.

I can't access the patents where I'm at right now, was there mention of the burn rate or how fast it could cut through, say, 3 or 4 inch plate steel? I could see it being used against lightly armored APCs and the like or maybe infrastructure targets if the I-beams aren't too thick.

Bert
December 14th, 2006, 11:58 AM
It's a demolition tool, not a weapon. Advantages would primarily be the lack of flying debris and noise/vibration from HE. Disadvantages would include the virtual certainty of a fire if any flammable materials were near the cuts being made.

I see this as akin to the niche occupied by the NONEX system for rock blasting- A bit more work than the HE solution to a cut, but it could be used on a construction site with far less disruption to other operations than clearing the place out for a conventional blast. I'd wonder how the economics relate to using a heavy cutting torch or thermal lance, if one didn't own the equipment allready.

nbk2000
December 14th, 2006, 05:44 PM
According to the patents, and the video, the reaction (and cutting) is done in a fraction of a second.

You'll also notice the lack of noise in the video, http://www.spectreenterprises.net/Video/LargeTorch.swf, just a hiss and the clang of the falling rebar. :)

Between the quiet nature, and the lack of alarm-triggering vibrations, there's much potential there for 'after midnight' applications. ;)

Further thinking on it made me realize that production could be simplified by using lost-wax or lost-foam for making the ceramic shell. Rather than load the thermite in a metal tube, load it in the ceramic (plaster?) body after it's been fired, and use a removable piece to block the throat of the nozzle when pressing the thermite.

I don't see any reason why a fire inhibitor couldn't be incorporated into the material so that, at the end of the burn, capsules of fire-suppressor are ruptured by the last traces of heat from the thermite, spraying it into the target, extinguishing any flames before they can spread (we're talking less than a second here).