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Flash Safety - Bill Ofca on Flash


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Posted

Yup, you are an ass, done with you, go away.-dag

 

Propaganda working in his head.... drumroll........badum tsss.....

[ goes into a denial when faced with reality of things. ]

Mission accomplished.

Posted (edited)
Thanks Peret. Edited by dagabu
Posted

Gentlemen, gentlemen... Please keep it civil here. Save that shit for Passfire.

 

In that connection, MediumRare, your avatar is a political statement, and I for one would appreciate it if you change it. No other reason for asking except to keep the peace.

Posted (edited)

Dagabu is the only one who has brought it up- no one beforehand brought it up. He couldn't even make a connection from the picture to the proof of inside job. That's how ignorant he is- he thought I just had a pic of WTC burning as if I'm "parading" the event. What a fool in denial. No, I will not reward his ignorant demands. :angry:

 

If I change my avatar it will be this:

 

http://2.bp.blogspot.com/_pf4aSh9rw2o/TEsIRR_PiJI/AAAAAAAABBg/7OPk1uV55QI/s400/911-inside-job-ostrich-head-in-sand.jpg

 

 

 

APOLOGIES FOR OFF TOPIC POSTS. Moderators should remove them as they please.

Edited by MediumRare
Posted

Dagabu is the only one who has brought it up- no one beforehand brought it up. He couldn't even make a connection from the picture to the proof of inside job. That's how ignorant he is- he thought I just had a pic of WTC burning as if I'm "parading" the event. What a fool in denial. No, I will not reward his ignorant demands. :angry:

 

No need to attack people here, Like Peret said, save that for Passfire. I simply objected to the display of the picture, the insults handed back are not necessary nor warranted.

 

-dag

Posted (edited)
This is a place to gather information and to ask for peoples advice, experience and help. If you want to get into a fight and stir the pot then go to a bar and cause problems there. Why piss off a bunch of people who are all here to share information about a hobby? Edited by xtr55
Posted
The only one getting pissed is dagabu and he has no right to question my avatar and tell me to remove it. That picture is associated with 9/11 inside job documentary, so I like to have it.
Posted

Dagabu is the only one who has brought it up- no one beforehand brought it up. He couldn't even make a connection from the picture to the proof of inside job. That's how ignorant he is- he thought I just had a pic of WTC burning as if I'm "parading" the event. What a fool in denial. No, I will not reward his ignorant demands. :angry:

 

APOLOGIES FOR OFF TOPIC POSTS. Moderators should remove them as they please.

I don't think anyone could have missed the connection, Mediumrare. It may even be an opinion held by a majority of citizens. That's not the point. This is not an appropriate forum to bring the subject up, and at least one person has been offended, for reasons you know nothing about. Don't compound your folly by offending him even more. I'm not a moderator here but if I was, I would suspend your account until you apologize and put up an inoffensive avatar.

Posted
Fine. But now I get to have Dagabu in my avatar. :whistle:
Posted

Thanks MR, lest get back to the topic at hand please.

 

I'm not sure that the mixture of Fe2O3 with fine magnesium would actually as would a salute? Would it?

 

-dag

Posted

Well... We definitely know that CuO/Al makes for salutes. So why not Fe2O3/Fine Magnesium? It should be reactive enough. I don't happen to have any -325 mesh magnesium do do the test with though. :/

 

The issue with the composition is that it doesn't produce very much gas at all even if it burns fast.

Posted

Well... We definitely know that CuO/Al makes for salutes. So why not Fe2O3/Fine Magnesium? It should be reactive enough. I don't happen to have any -325 mesh magnesium do do the test with though. :/

 

The issue with the composition is that it doesn't produce very much gas at all even if it burns fast.

 

Little gas = Little boom?

 

-dag

Posted
well, solid products that arent "gas" are produced, but it should still boom because they take up more volume than original.
Posted

CuO thermite makes great noise, but has no moving power to it, like regular flash does. It would be good for salutes, though.

Fe2O3 even with the finest Mg isn't going to match CuO thermite in noise making. Poor salute substitute and more expensive.

Posted

Little gas = Little boom?

 

-dag

 

Hey dag, stopped by to see what you wrote. Flash makes little gas too (see Conklin's book) Its the speed of the burn that makes the boom, even if unconfined at about 2 ounces or more (critical mass).

 

The CuO2/magnesium mix as well as the FeO2/magnesium mix are basically therrmite mixes. I would think the problem is the high ignition temperature to get the mix going. A salute would be hard to get going, and the burn speed is not as high as flash. Might not work at all. I would be surprised and stand corrected if it did. With the price of magnesium, it would be an expensive salute. Just my two cents. - Bill

Posted
. I would think the problem is the high ignition temperature to get the mix going.

 

Fe2O3/Mg is pretty easy to light as most Mg thermites. Could literally be lit with a match. The finer Mg, the easier.

Problem then becomes the hazard of that extra fine Mg- autoignition problems and such.

Posted (edited)

Hey dag, stopped by to see what you wrote. Flash makes little gas too (see Conklin's book) Its the speed of the burn that makes the boom, even if unconfined at about 2 ounces or more (critical mass).

 

The CuO2/magnesium mix as well as the FeO2/magnesium mix are basically therrmite mixes. I would think the problem is the high ignition temperature to get the mix going. A salute would be hard to get going, and the burn speed is not as high as flash. Might not work at all. I would be surprised and stand corrected if it did. With the price of magnesium, it would be an expensive salute. Just my two cents. - Bill

 

Bill,

 

Flash of any kind is really not a strong suit for me in any way, I am asking because I really don't know if the bang! is due to rapid expansion only or if gas generation is part of the formula for a good report. Thanks for the explanation, old dogs can learn new tricks after all! ;)

 

-dag

Edited by dagabu
Posted

CuO thermite makes great noise, but has no moving power to it, like regular flash does. It would be good for salutes, though.

Fe2O3 even with the finest Mg isn't going to match CuO thermite in noise making. Poor salute substitute and more expensive.

 

i believe pains wessex in the uk, used to use a copper oxide mix in their signal maroons to

alert the local lifeboat crews, so it obviously works.

 

dont think they use that now though.

 

dave

Posted

could be the rapid heating and expansion of air in the casing,kind of like lightning does to produce thunder.

I read in some pyrotechnic literature that you should have an air gap in salutes

maybe thats got something to do with it.

Posted
.

I read in some pyrotechnic literature that you should have an air gap in salutes

maybe thats got something to do with it.

 

Well, that is interesting. Any explanation as to why that would be the case?

 

-dag

Posted

Well, that is interesting. Any explanation as to why that would be the case?

 

-dag

 

The air or space gap recommended inside of salutes is to keep the flash powder loose and free moving so it does not get compacted or compressed. When you fill a small tube with flash powder and compress the powder such as hand tamping it with a dowel, it will burn slow like a flare. Keeping the powder loose allows the flame to propagate rapidly through the mass increasing the likelihood that it will explode violently, as intended. Some of the old timer fireworks makers would sometimes add bran or coarse sawdust as a bulking agent to keep the powder loose and free flowing. That was in a time when chemical formulas for flash were not as fine tuned to the best decomposition reaction as today, or the mix relied on poor quality aluminum, or aluminum flake not as fine as what is available today.

 

More modern salute makers will use a bulking agent such as Cab-o-sil (fumed silica) to do the same, but is is probably not necessary. A bit of free space in the salute casing accomplishes the same purpose just as effectively. It is well known by professional manufacturers that salutes sitting in a magazine for long periods of time (more than a year or sometimes less) can settle from gravity and compact the flash powder into a solid mass. Moving the salutes around and handling them to get ready for packing out a show will loosen the powder again if there is an air gap allowing it to happen. My personal believe is that all this is moot when finely divided powdered chemicals are mixed to make flash in the standard ratio recognized today as 70:30, and using quality dark aluminums such as Indian black. or German Black. In the old literature, you can find lots of different formulas for flash powder that use different oxidizers than KCLO4. Many used KNO3 or BaNO3 or combinations with different ratios to aluminum, some with sulfur or antimony sufide that are not the standard today. In those days of old, compaction from gravity was a real issue to what was a poor excuse for good salute powder. Potassium Chlorate (KCLO3) was used dangerously with sulfur or antimony to improve flash that was made with very poor quality aluminum flake powder that was not as fine or clean as today, and the aluminum was loaded with animal fat coatings (steric acid or free fatty acid) used during the ball milling or hammer milling of the aluminum. Please note that Potassium Chlorate flash mixes are highly dangerous and it is not recommended for making flash. Please avoid it unless you have a death wish.

 

Bill

Posted

it appears that they recommend to leave an air gap so as to avoid tamping and so the end-plug of whatever description doesn't come into contact with the powder at any stage.

its an old australian pyrotechnic book published in 1989,some of the compositions contain paris green,red arsenic,calomel, even picric acid as a colour enhancer.

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