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The Diagonal Column Cut . . .

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Apr 5, 2007
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We've all seen this picture countless times:

pic87970.jpg


Here is one truther site (among many) that insists this cut could not have been made by a blowtorch. The guy seems to know what he's talking about (but then don't they all :)). Some of the reasons he gives for his conclusion are:

1. No cut from a torch accumulates that much hanging slag. Most slag is blown away; this volume would indicate melting with abundant, directed heat but with little or no air pressure eliminating blow torch possibility.

2. Slag cools too quickly. To drip that long, with the beam itself vertical, that much slag would separate and fall to the ground, and would never drip that far even with that bad a cut. The suggested explanation of Thermate with no air pressure at a much higher temperature would account for this.

3. No experienced torch cutter would take a diagonal cut on 4” thick steel tube. And why would even an inexperienced one do so? There would be no possible reason to do it where a horizontal cut is possible, even if above the cut was bent in the direction towards the lower horizontal cut. And the upper horizontal cut can be seen to be cut also on a downward angle thru the steel. No one would angle from horizontal on 4” thick steel and increase the cut to 5 or 6” thick.

4. No one would cut on an angle thinking that it will cause a standing structure to fall a certain direction, just ask any lumberjack.
Any metal cutter would also question why the rear cut is not a straight line and it dips drastically in one spot, this indicates possibly the remains of a round cut which would allow inserting Thermate charges inside of the tube to conceal them (more on this regarding the second photo).



I am particularly interested in learning two things. First, does, in fact, the quantity of slag shown on the column argue against the use of a blowtorch? Is there a blowtorch expert or two amongst us who knows?

Second, is it even feasible that thermite can be used to make such a diagonal cut? I have a vague recollection of "possible" machines with patents pending that might do such a job but know of nothing commercially available today that might do so.

Anyway, I apologize in advance if this horse has already been beaten to death on this site and if it's only my stupidity :blush: that prevents my finding that dead horse. If that is the case, please point me in the direction of that particular thread (or even better, of that specific post) and I'll be on my way.

Thanks.
 
1. No cut from a torch accumulates that much hanging slag. Most slag is blown away; this volume would indicate melting with abundant, directed heat but with little or no air pressure eliminating blow torch possibility.
i cant besure of the validity of this statement, however other cutting devices such as thermal lances do not use much air pressure

2. Slag cools too quickly. To drip that long, with the beam itself vertical, that much slag would separate and fall to the ground, and would never drip that far even with that bad a cut. The suggested explanation of Thermate with no air pressure at a much higher temperature would account for this.
the statement about slag again may or may not be true, but thermite while reacting is a liquid, and theres no way to hold it in place, i would say its impossible to get thermite to cut at a 45 degree angle, let alone that cleanly

3. No experienced torch cutter would take a diagonal cut on 4” thick steel tube. And why would even an inexperienced one do so? There would be no possible reason to do it where a horizontal cut is possible, even if above the cut was bent in the direction towards the lower horizontal cut. And the upper horizontal cut can be seen to be cut also on a downward angle thru the steel. No one would angle from horizontal on 4” thick steel and increase the cut to 5 or 6” thick.
a poster here stated the exact opposite, that an experienced metal worker would cut on a downward angle so the slag would preheat the metal and make the cut go faster, makes sense to me
 
Look carefully at the photo. It appears that slag did fall on top of the debris that's leaning against the column.

I have posted many photos from the site that look much the same.

The comment that no experienced ironworker would make a diagonal cut like that is utter nonsense. Ground Zero photos show such cuts being made by ironworkers. The wide view of that scene shows the very steep and uneven terrain, with sharp dropoff in the foreground. Ironworkers had to makes cuts from myriad awkward positions, often reaching as far as they could to get the flame on the steel. That commenter seems to think that this was a normal jobsite with normal working conditions. It was anything but.

All they have to do is talk to ironworkers who were there, but they won't.

ETA:

8790462a9da8a992a.jpg
 
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Looks like this is the place to come to do one-stop shopping for all my debunking needs!

Thanks for the excellent replies. This is exactly what I'd hoped to get.

Gravy, know where I can go to view those photos?
 
We've all seen this picture countless times:


I am particularly interested in learning two things. First, does, in fact, the quantity of slag shown on the column argue against the use of a blowtorch? Is there a blowtorch expert or two amongst us who knows?

I am not an expert, but I have worked in manufacturing for over 10 years and have supervised large groups of millwrights and ironworkers. There is no reason at all that you can not have alot of slag hanging off of a beam that thick. Since you have no idea of what was overhanging the beam, you have no idea of how long the torch was applied and how hot the surrounding air was to afford cooling to the beam.

I have seen this brought up also about how no good millwright would cut such a large beam at 45 degrees. Once again, the amount of material on top probably necessitated ahving to cut at that angle.

Finally, it may not have been cut with a torch, but with a plasma cutter. While this is a slim possibility because they are much less efficient at cutting such heavy steel, it is a possibility.
 
Some CT Nut said:
3. No experienced torch cutter would take a diagonal cut on 4” thick steel tube. And why would even an inexperienced one do so? There would be no possible reason to do it where a horizontal cut is possible, even if above the cut was bent in the direction towards the lower horizontal cut. And the upper horizontal cut can be seen to be cut also on a downward angle thru the steel. No one would angle from horizontal on 4” thick steel and increase the cut to 5 or 6” thick.

I'm no expert in these things, but allow me to give my layman reasoning.

I would hypothesize the angled cut may have been made to ensure the beam fell in a particular direction - like chopping a tree down. If the cut was made horizontally, the beam would have been prone to falling in any direction at any moment.

My 2c.
 
i cant besure of the validity of this statement, however other cutting devices such as thermal lances do not use much air pressure
Thermal lances were in common use at GZ. They do use high pressure, some over 150 psi.
 
I'm no expert in these things, but allow me to give my layman reasoning.

I would hypothesize the angled cut may have been made to ensure the beam fell in a particular direction - like chopping a tree down. If the cut was made horizontally, the beam would have been prone to falling in any direction at any moment.

My 2c.
That's my thought too. First thing they had to do at GZ was make the area safe to work in, so they had to cut down the tall columns hanging precariously overhead.
 
I'm no expert in these things, but allow me to give my layman reasoning.

I would hypothesize the angled cut may have been made to ensure the beam fell in a particular direction - like chopping a tree down. If the cut was made horizontally, the beam would have been prone to falling in any direction at any moment.

My 2c.
It's likely that a column of that size was supported by a crane when it was cut (if a substantial portion was being removed). That was SOP, to prevent injuries and further damage to structures below. Tension from the crane cable made cutting and release easier.
 
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Looks like this is the place to come to do one-stop shopping for all my debunking needs!

Thanks for the excellent replies. This is exactly what I'd hoped to get.

Gravy, know where I can go to view those photos?
I've posted some here before, but they're no longer up. I'll post some when I get the chance.
 
It's likely that a column of that size was supported by a crane when it was cut. That was SOP, to prevent injuries and further damage to structures below. Tension from the crane cable made cutting and release easier.

Ah, yes - of course. Why didn't I think of that? :o

I guess there may still be a chance of injury if the thing swings the wrong way, though.

Has anybody here asked any of the contractors involved about the purpose of the diagonal cuts? I know no CTer would have.
 
Here's a photo of just such a diagonal cut, complete with the ironworker making it:

37845fb020241390.jpg


The same in a closer view, clearly showing the angle of the cut:

37845fb02025ffb9.jpg


Also, notice the striated appearance of the cut surfaces in the photo in the OP. Those are called "drag lines" and they're normally found on the edges of metal cut with an oxy-fuel torch. See here for some pictures of examples. You can use the arrow buttons below the picture to click through the explanatory text.

Finally, notice that on the two inside faces we can see, the slag is clinging to the inside surface of the column, and on the diagonally cut side we see from the outside, there's no visible slag. On the lower straight cut, the slag is clinging to the outer face of the column.

If these cuts were made by thermite devices attached to the column, the devices would have to have been attached to the accessible outer faces; they should all have caused slag to deposit on the same faces- inner or outer. Why would three behave in one way and the fourth behave oppositely?

What this observation suggests is that the upper straight cut and the two diagonal cuts were made first, from the outside of the column, and the column was then bent down, hinging on the uncut side, with the final cut being made from the now-exposed inner face.

That, in turn, suggests the use of a torch during the site cleanup, not thermite prior to the collapse of the building.
 
The patterns of the cuts is evident as is the uncut though hinge joint.

howtocutasteelbeam.jpg


I am particularly interested in learning two things. First, does, in fact, the quantity of slag shown on the column argue against the use of a blowtorch? Is there a blowtorch expert or two amongst us who knows?
Yes it was probably an oxygen lance it was definitely not thermite. Oxygen lances use a tube of burning steel to produce sustained temperatures of 3000c by combusting it with oxygen the result is actually burning not cutting thought a beam. The oxygen lance also leaves more black Iron oxide on the steel.

Second, is it even feasible that thermite can be used to make such a diagonal cut? I have a vague recollection of "possible" machines with patents pending that might do such a job but know of nothing
commercially available today that might do so.

NO thermite would not do that as thermite mostly produces melted iron and melts and does not com-bust the steel with oxygen as seen in the photos.
 

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