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Marsh
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[*] posted on 28-7-2006 at 19:57
Videos...


I know we all love video footage, so I'm posting two underwater ignitions from a couple of days ago. I figured I'd start this thread so I can add more videos as I film them. Any other member vids are welcomed.

This is nothing special, just 70/30 flash powder...(I'm not big on flash, but the camera died for the underground PETN. I will however film this again).

The first video is 25g's.

The second video is 75g's.

The water is low right now, and both were under approximately only 1ft of water.

What I found interesting, is that the 25g charge vibrates the camera slightly. The 75g charge however does not (probably due to more gas escaping the shallow water). Shows lower frequencies do travel!

(Sorry about the video host quality, double-click the video frame for fullscreen.)
25gm 1ft water.mpg

75gm 1ft water.mpg


[Edited on 29-7-2006 by Marsh]
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Deceitful_Frank
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[*] posted on 29-7-2006 at 09:42


An excellent idea to have a thread devoted to various members' videos!

This is one of my favourites from nearly a year ago. Rather kewl I must admit but the ANNMX composition that I devised with the help of a US patent was new to me.

Enjoy...


http://media.putfile.com/Kewl

[Edited on 29-7-2006 by Deceitful_Frank]
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Deceitful_Frank
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[*] posted on 28-8-2006 at 11:12
My first compound detonator


Well I've just today tested my first compound detonator.

It consisted of a 4cm long 5/16 OD brass tube epoxied closed at one end and then with 0.75 grams of recrystalised ETN and 0.2 grams of HMTD pressed inside at 3500 psi.

50mg of loose HMTD was sprinkled in on top giving a total of 1 gram fill, a blu-tak wrapped visco fuse inserted and poked down.

Finally the whole deal was sealed shut with epoxy.

The target was a 3mm thick aluminum sign that conveniently "fell off" its securing post.

http://media.putfile.com/ETN-cap
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Marsh
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[*] posted on 28-8-2006 at 14:54


Quote:
Originally posted by Deceitful_Frank
...recrystalised ETN and 0.2 grams of HMTD pressed inside at 3500 psi.


Wow, I never realized it was safe to put such pressures on these energetic materials. Does 3500psi worry you at all?

For PETN I usually hand press with light pressures and glue the ends like you.
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Deceitful_Frank
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[*] posted on 28-8-2006 at 22:56


3500 psi isnt THAT much pressure in comparison with those reached to press commercial caps. As you will see from the video I am of substantial build and I was pressing using my full bodyweight over a 1/4 inch dowel. If you read up on your physics you will see that 3500 psi isnt that difficult to accomplish.

I used a home-made cap press and stepped down off the gate that you see in the video onto it, 3 inches of plywood protecting my feet though I must admit my ears weren't, and should have been plugged!

EDIT:

ETN at 3500psi FAR outperforms hand pressed PETN.

...For maximum reliability and full initiation of pretty much any explosive I would seriously suggest that you invest some time into building a cheap improvised cap press :)

[Edited on 29-8-2006 by Deceitful_Frank]
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