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Mr. Wizard
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My personal opinion is there was no 'demolition' at the WTC. The heat involved in the fires and the destruction of both the sprinkler system and the
heat protective coatings on the structural steel would be enough to ruin the strength of the building. Steel actually has a low specific heat and
heats up quite quickly, hence the need for the sprayed on coating. Once the temperature reaches 900F it's essentially as strong as wet cardboard. I
have seen building involved in normal everyday fires with twisted I beams that have sagged and failed. No exotic thermit, no shaped charges, nothing
but burning wood and building contents. There are enough questions about the terrorist attack that are unanswered without looking for more.
As to cutting steel, has anyone ever seen a portable plasma steel cutter? A cutter could be operated from power available in the building, as could a
portable compressor needed to operate the cutter. The cuts are very smooth, but are distinctive.
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Panache
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Mood: Instead of being my deliverance, she had a resemblance to a Kat named Frankenstein
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Quote: Originally posted by grndpndr  | Is it terribly far fetched the 'explosions', witnessed by a majority of civilians
who couldnt distinguish an explosion from high air pressure release As the WTCs 100s of acre sized stories pancaked causing explosive air
compression/tremendous noise as the millions of pounds of concrete and steel impacted the floor beneath it?Of course they thought the impacting floors
were exploding.Nothing mysterious or complex about that.Difficult to believe this is even being discussed seriously on this forum.
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i don't think it is being discussed seriously only that cut and paste comment by JohnW which i'm certain he doesn't agree with but it's been funny
listening to everyone one pound down on the conspiracy, i mean its so ludicrous it hilarious, however Princess Dianna was killed by mi6/5 and that
french mob upon orders of the queen and prime minister because she was carrying a islamic baby that had the potential to bring down the monarchy. I
mean its obvious, makes perfect sense, lucky too as i'd be lost without my lordship stipend and title.
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grndpndr
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I Misspoke, I dont think anyone seriousy buys into a conspiracy theory on this forum.It is refreshing to see the 'conspiracy' roundly criticized
for a change.Its distressing to see the poll #s of how many actually believe there was some sort of gov conspiracy.If they tuly believe that wouldnt
the be duty bound and morally obligated to respond vigorously?
Talk about anachronisms/ undeserved entitlements/welfare:
Anywhere top GB/'Royal'Family?
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quicksilver
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| Quote: Originally posted by Mr. Wizard |
As to cutting steel, has anyone ever seen a portable plasma steel cutter? A cutter could be operated from power available in the building, as could a
portable compressor needed to operate the cutter. The cuts are very smooth, but are distinctive. |
I'm glad you know that the "911 conspiracy" is BS. But as to plasma cutting - portables can't cut inches, they cut about 1/4 with SEVERAL PASSES. The
power utilized would spike the electrical system on a secure structure as well as emit so much hi-frequency that it could not be done in a clandestine
fashion. The duty cycle is only 20% for those if you're trying to really cut beams. The more professional cutters need a water spay.
The "911-Truthers" have been so roundly beaten in their fantasies that they have backed WAY off; except for the really stupid ones or the nut-jobs.
It just simply could not have happened. Such a "black-bag" job was just not the same as crawling around Vietnam's waters and saying the ship was
further away.
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JohnWW
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The thousands of professional engineers (mostly civil and mechanical) and architects who are members of Architects & Engineers For 9/11 Truth, and
who are better-qualified than you to judge, disagree with you, Quicksilver.See:
http://www.ae911truth.org/aboutus.php ; and also
http://www.911truth.org/ ,
http://www.911blogger.com/node/22725 ,
http://www.infowars.com/1000-architects-engineers-officially... ,
http://www.youtube.com/watch?v=ssuAMNas1us ,
and the video clips and full-length documentaries linked on
http://www.google.co.nz/search?q=%22architects+and+engineers...
[Edited on 13-4-10 by JohnWW]
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bquirky
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Off topic..
There is another possibly dangerous trend that seems to be emerging in society
that is the idea that conspiracy's are pure fiction.
and any interpretation of events or evidence that suggests something that could be construed as a 'conspiracy' is automatically an obsered fantasy.
The truth is that conspiracy's of all kinds are very real happen every day and result in real harm to people.
some examples are
the Archer Daniels Midland price fixing afaire
Amcor and Visy cardbord box price fixing convictions
the Watergate scandal
Evan the 911 plot was a true conspiracy
if someone had cottoned on to any of these things and started to talk they would have been laughed at as cranks.
groups of people sit around and plan nasty shit all the time and nasty shit can be well... nasty
lets bust out one right now..
Swine flue: real but massively exaggerated by vaccine manufactures,self justifying bureaucrats and politicians looking for a quick poll boost by
'swift action'.. now low and behold there are warehouses full of unused vaccines getting closer to expiring at public expense.. and whats worse.
there are people out there in poorer contreys that could really be helped by vaccines for actual serious diseases
so.. did a group of people sit around and plan this ???
I dont know.. but isn't it worth looking into ? wouldn't you want to know ?
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watson.fawkes
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Well, I went and looked at this site, and its first paper,
"Explosives Found in World Trade Center Dust". You can apply all the science and high-tech gear that you want, but if you're using it to justify a
pre-existing conclusion, you're not doing science and you're philosophically unqualified to judge anything. And that's the character of this paper.
There's not a single alternate hypothesis in the paper. It quotes uncritically that awful Jones paper I ridiculed above, the one that does reactivity
experiments with no regard to surface area, even as this paper uses it to justify conclusions about "nano-thermite". There's no discovery or inquiry
here; it's all of the form "this observation is consistent with our hypothesis". That's not science, but a form of religious practice called
"proof-texting".
@JohnWW, you're making an appeal to authority that's not warranted. These people are profoundly not more qualified than the regular participants on
this board.
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The_Davster
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It would be best for this thread to stay on the thermite topic and not on the WTC....
Nanothermite usually burns too fast for any significant heat transfer and would be useless for melting. It is being considered for primer
applications and microscale propulsion, not for any thermal work...
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gregxy
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I have used plasma cutters and oxyacetelene torches to cut
steel and other metals. It is not the kind of thing you can
hide in an office envoromnent, lots of smoke, sparks, hissing
noise etc.
And why use thermite at all? A much smaller weight/volume
of HE cutting charges would be needed. And why place
charges on every floor? Cutting the floor that the plane
hit and dropping the building sideways would have the
same effect.
The common explaination of what happend at WTC is
completely consistent with the physics.
Here is a believable conspiracy theory (if you need one):
The CIA found 20 nice guys from the middle east, gave them
LSD and brainwashed them into hating America. Then
they trained them in how to fly jets, bypass security,
showed them the "target points" in the WTC gave them
the reqd. money and let them have at it.
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grndpndr
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Some folks do have a psychological need for a govt etc conspiracy
thus giving the act deeper meaning.Its unacceptable to thier sense of the world that a bunch of mutts could cause such pain.Every disaster I can think
of manmade and natural has its conspiracy theory devotees.Not my conclusion look to the Pschiatric community.But it makes a lot more sense than
"truthers".Hindenburg,Pearl Harbor,Camelot,Now 9-11.
Shit happens folks and I rather doubt its gods will or satans minions of yesteryear or government conspiracy now.
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The WiZard is In
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| Quote: Originally posted by The_Davster | It would be best for this thread to stay on the thermite topic and not on the WTC....
Nanothermite usually burns too fast for any significant heat transfer and would be useless for melting. It is being considered for primer
applications and microscale propulsion, not for any thermal work... |
It would be best for this thread to stay on the thermite topic and not on the WTC....
Amen.
Now on to da topic.
It would be worth noting that aluminium iron oxide (all three work) is not the only thermite. Spitzer and Comet, Journal of Pyrotechnics 26 (2007)
60-64. Synthesis, structural and reactive characterization of miscellaneous nanothermites, for instance describes WO3 thermite.
The most common non-iron thermite is Cadweld® copper oxide/aluminium thermite used to weld copper, usually copper grounding wire.
Here do be a few others, from da Welding Handbook.
3FeAl + 8Al ----> 9Fe + 4Al203 (5590'F/3088-C) 719.3 Kcal
3FeO + 2Al 3Fe + AL203 (4532'F/2500-C) 187.1 Kcal
Fe203 + 2Al 2Fe + Al203 (5360'F/2960'C) 181.5 Kcal
3CuO + 2AI 3Cu + Al203 (8790'F/4865'C) 275.3 Kcal
3CU20 + 2AI 6Cu + Al203 (5680'F/3138'C) 260.3 Kcal
3NiO + 2AL 3Ni + Al203 (5740'F/3171'C) 206.6 Kcal
Cr203 + 2AI 2Cr + Al203 (5390'F/2977'C) 546.5 Kcal
3MnO + 2AI 3Mn + Al203 (4400'F/2427'C) 403 Kcal
3MnO2 + 4AI 3Mn + 2Al203 (9020'F/2771'C) 1041 Kcal
[One of these values is wrong! /djh/]
djh
-------
But science, spurred on by its energetic notions, approaches
irresistibly those outer limits where the optimism implicit in logic
must collapse. For the periphery of science has an infinite number of
points. Every noble and gifted man has, before reaching the mid-point
of his career, come up against some point of the periphery that defied
his understanding, quite apart from the fact that we have no way of
knowing how the area of the circle is ever to be fully charted. When
the inquirer, having pushed to the circumference, realizes how logic in
that place curls about itself and bites its own tail, he is struck with
a new kind of perception: a tragic perception, which requires, to make
it tolerable, the remedy of art."
Friedrich Nietzsche
The Birth of Tragedy 1872
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Ramiel
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Any more discussion of thermite in current affairs will be removed without comment.
Caveat Orator
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chief
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optimizing the heat-transfer into the material
The termal conductivity of the steel may play a role: To cut it faster than this conductivity permits
==> the surface, which faces the flame, must be blown off quickly enough, or reacted away ...
So maybe a non-equilibrium-process must be considered ...
==> A standard flame will transfer heat more slowly into the steel, heating it up halfway to the core ...
==> but a quick hot flame, with maybe reactive components, might eat the steel away more quickly than the heat can get diffused ...
Maybe that's why sulfur is said to be a component of some thermites ... : The sulfur-vapor or any oxide of it would at the temperatures maybe go sort
of "through" the metal ... ... ; part of the heat would be produced by the reaction of the sulfur with the steel ...
=================
If the reaction would go faster than the temperature could be diffused, then it might be called a "thermal shockwave" ...  
==> Ever anyone heared of such a thing ?
[Edited on 14-4-2010 by chief]
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The WiZard is In
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| Quote: Originally posted by chief | | Suppose I have a 15mm steel-rod and want to melt through it (just for sports, or because maybe it's too hard for any tool, and acid would take too
much time ...) [Edited on 5-4-2010 by chief] |
Back to the drawing board.
Band sawed an 4" length of 2" PVC in half, put on 2 band clamps,
mixed up 82 g aluminium (atomized was used for convince)
and 115g calcium sulphate (rounded values does not add to 200)
added water qs.
Poured in to the mold - inserted 1/2 bolt covered w/ tape,
when a bit hard removed bolt and enlarged hole w/ 1/2"
rebar.
Oven dried to constant weight. 170-180 gms. I forget.
Placed rebar on sawhorse with Ca sulphate thermite three
inches in. Warped Mg ribbon round... lite with torch ...
ribbon burns... nothing.
Time my trusty acetylene/air torch. Nice fire. Burns about
1/3 of its mass and falls off. Leaving rod hot enough to handle.
Next time ... find way to keep thermite in contact w/ rod
... use a LOT more. I am considering putting the thermite
in a flower pot so the aluminium oxide dross can run down -
flow over the rod, however. the aluminium oxide slag is not
very fluid, me thinks conventional thermite will be a better choice.
Will report back.
And a quick note for the pendantic-fussbudgets who do not
like my posts. Do you know how hard it is for me to
find material you don't find interesting - want to read?
Feel free to take your list of what you find acceptable
down the hall to the Chaplin's office and leave it there.
Free of charge the Chaplin will also punch your TS Card.
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The WiZard is In
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| Quote: Originally posted by The WiZard is In | | Quote: Originally posted by chief | | Suppose I have a 15mm steel-rod and want to melt through it (just for sports, or because maybe it's too hard for any tool, and acid would take too
much time ...) [Edited on 5-4-2010 by chief] |
Back to the drawing board.
Band sawed an 4" length of 2" PVC in half, put on 2 band clamps,
mixed up 82 g aluminium (atomized was used for convince)
and 115g calcium sulphate (rounded values does not add to 200)
added water qs.
|
If fist you don't succeed use a bigger hammer.
Knocked together a 5" square box using 5/4 common pine
and my 2" stapler. Drilled hole for rod. Inserted plastic bag
filled with 500gm of aluminium/sulphate slurry. Allowed to harden.
Discovered P of P swells when it hardens. Remove on side
of box. Dry in oven to constant weight. Place cast thermite
in box. Screw side back on. Inset rod and two thermite campfire
starters (say 450gms). Added standard starting mixture
and a length of fuse. (I was not prepared to light this w/
my air/acetylene torch — put's me tooooo close.)
Nice display flames 3 foot in the air with white fire and
sparks. After 5-10 seconds. Bottom of box looks a volcano.
Knock scoria off rod --- red hot --- not melted.
The next try will be using iron oxide thermite where I can
get the molten metal to flow over the rod. Will make
a papier- mâché container using a flower pot for a mold.
Byda in thermite welding the heat the weldment to red
heat before welding so it doesn't suck the heat out of
the themite produced molten meal.
Looking out window see box is still burning.
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The WiZard is In
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Ok. Actually it wasn’t ok it didn’t work.
| Quote: Originally posted by chief | Suppose I have a 15mm steel-rod and want to melt through it (just for sports, or because maybe it's too hard for any tool, and acid would take too
much time ...)
==> Probably the choice would be thermite ... |
Ok. Actually it wasn’t ok it didn’t work.
Stapled up a box from scarp plywood open at the top with a 5/16”
(arbitrary size) hole in the bottom. Made two side longer than the
over by ‘bout 3”. Dilled hole in longer of the two legs to hold a
length of ½” rebar under the hole in the boxes bottom. Appx. ¾”
below the hole.
After finding my eBay aluminium was aluminium paste (35%
mineral sprits) which if you do not remove it …. you convert your
Fe3O4 into nonmagnetic black mass.
After getting the mineral spirits out… mixed up 750 gms of 2.75/1
put it la box w/ the standard barium peroxide magnesium igniter,
because it was toooo windy too use magnesium ribbon, a first fire
composition and fuse was used.
Flame – smoke – sparks, pretty. Burns out… the molten metal
when it reached the bar cooled rapidly (which is why in thermite
welding the weldment is preheated to red heat) forming a blob,
which cooled the metal coming out of the box stopping the flow.
Result – a lot of iron in the now burning box.
If there were to be a next time – use a smaller hole in the bottom
of the box. Move the bar further away from the boxes bottom.
Use courser aluminium/black iron oxide. As you may have noticed
if you have watched La Myth Busters {who for whatever
reason used red iron oxide… then so did them on Save it keep it
(?)} fine reactants burn much too rapidly.
Engineering Design Handbook. Military Pyrotechnics Series : Part
One. Theory and Application (All 4 volumes are a fee DL)
sez. — … iron oxide scale [hammerschlag] and granular
aluminum. Large flake aluminium is no problem, “iron oxide
scale” is. Checking my ever useful copy of Graton and Sales,
Ore Deposits in the United States 1933/1967. AIME., to
refresh my memory. I believe the nearest magnetite mine to me
closed some years ago, alas.
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chief
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It didn't work for me either ...
==> all the heat goes anywhere, and maybe 5 % into the rod ... which doesn't even glow ...
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The WiZard is In
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| Quote: Originally posted by chief | It didn't work for me either ...
==> all the heat goes anywhere, and maybe 5 % into the rod ... which doesn't even glow ... |
Next up. Put lateral tension on the rod so it will pull apart if
melted — encase the rod in la box so it stays in close contact w/
the molten metal.
djh
----
In Italy for thirty years under the Borgias they had warfare,
terror, murder, bloodshed -- and they produced
Michelangelo, Leonardo da Vinci and the Resaissance. In
Switzerland they had brotherly love, five hundred yeas of
democracy and peace, and what did they produce?
The cuckoo clock!
(George) Orson Wells, 1915-1985
Speech added to Graham Greene's script for
The Third Man, 1949
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The WiZard is In
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Today's engineering failure
| Quote: Originally posted by chief | Suppose I have a 15mm steel-rod and want to melt through it (just for sports, or because maybe it's too hard for any tool, and acid would take too
much time ...)
==> Probably the choice would be thermite ... |
Today's engineering failure —
Stapled together a 2 1/2 x 3 1/2" id box from ratty 1/2 plywood.
Drilled hole through and inserted 1/2 threaded rod, washer/nut
on one end, two compression springs on the other to pull the
rod apart when it melted.
Same old 750 gms 2.75/1 magnetic iron oxide/aluminium with
the standard BaO2/Mg w/ a Mg ribbon fuse.
Stapled ratty 1/2" plywood box's do not hold molten iron
really well! Melted one end of the spring and removed its temper.
Screwed together a 3/4" common pine 2 1/2" sq (inside dia.) box.
Filled bottom w/ an inch or so of Durhams Rock Hard Water Putty.
Will order up a strong spring from McMaster Carr on the morrow.
Standby for follow up.
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Mr. Wizard
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I would be real careful about using anything that had a water component in it to contain a thermite reaction. The worst case scenario has the
reaction going to completion , with a big hot pool of molten iron, covered by white hot alumina, then the steam generated by the heat on the water
putty, plaster, or concrete blasting the whole mass skyward into the air.
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The WiZard is In
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| Quote: Originally posted by Mr. Wizard | I would be real careful about using anything that had a water component in it to contain a thermite reaction. The worst case scenario has the
reaction going to completion , with a big hot pool of molten iron, covered by white hot alumina, then the steam generated by the heat on the water
putty, plaster, or concrete blasting the whole mass skyward into the air.
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Granted one can never be — Too rich, good-looking or safe.
Durhams Rock Hard Water Putty dries ... well rock hard.
Me thinks like concrete the water is part of a reaction and is
not available after hardening.
---------
Chemical demo goes out of control
An explosion occurred during a chemical demonstration at the University of Illinois,
Urbana-Champaign, earlier this month. The widely used demonstration of the thermite
reaction-which involves the reaction of iron oxide and powdered aluminum to form iron
and aluminum oxide-was part of the university's annual Engineering Open House for
local high school and grade school students. There were 200 to 300 people in the
chemistry lecture hall at the time of the explosion. Four teachers and 23 students were
taken to the hospital, where they were treated and released. The injured suffered first-
and second-degree burns and minor cuts. Chemistry professor Steven S. Zumdahl,
who was conducting the demonstration, says it had just been run successfully using
sand as a receptacle for the molten iron. But when the sand was replaced with water,
something went wrong. Jiri Jonas, head of the department of chemical sciences, says a
committee, including university and local safety experts, has been appointed not only to
determine what went wrong with the thermite demonstration, but also to review all
safety issues surrounding the open house.
March 12, 1990 C&EN23
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The WiZard is In
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Success
| Quote: Originally posted by chief | Suppose I have a 15mm
steel-rod and want to melt through it (just for sports, or because
maybe it's too hard for any tool, and acid would take too much time
...)
==> Probably the choice would be thermite ... |
Screwed together (well screwed together) a 2 1/2" id box from
3/4" pine. Drilled 1/2 hole 'bout 3/4" OC from the bottom —
1/2" threaded rod through. Used a (as described in the
McMaster-Carr catalogue) 1", 1/2" hole size, heavy load (Rate
lbs/inch - 230.4) 6" long, Steel Die Spring for pull.
750 gms of Fe2O3/Al 2.75/1 thermite, BaO2/Mg ribbon igniter.
Burns like a volcano — and yes the rod pulled in half.
Dripping thermite on the rod to melt it requires a courser mesh
iron oxide/aluminium than I currently posses to slow its burning.
I will stay w/ my plasma or oxyacetylene torch, WiZzer (pneumatic
cutoff tool) or if I really want to have fun pull it apart w/ either my
60 or 100 ton hollow cylinder - hydraulic ram. 5/8" and lager bolts
make a soul satisfying sound when they go, and if were not for
having a 5-gallon pail over the setup the bolt would hit the ceiling.
This afternoons project a wasp light for the tent caterpillars.
I usually turn them into tent caterpillar pâté with my 12 Gauge,
however, these are located just off the road. So.........
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