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Author: Subject: A more durable improvised detonating cord?
Deceitful_Frank
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[*] posted on 24-7-2010 at 02:56
A more durable improvised detonating cord?


Hey guys it has been a while!

Just wondered if anyone can help with this one...

I have experimented at length with ETN and obtained great results. It will initiate another cord with a 3cm overlap, ANNM etc. you can have some SERIOUS fun with a few metres of well made 10g/m!

Making it isn't without difficulty though. Using a 1m long strip of Al foil 4cm wide with an "M" crosssection makes getting an even bead of powdered ETN fairly easy and once folded and rolled up in to a long cigerette a couple layers of PIB self amalgamating tape will give you a really well pressed core and a tidy result... untill you kink the cord and the foil inside snaps! then the PIB constricts the core and you end up with what looks like a string of sausages and reliability is pretty much gone.

What we need is a material to roll up the ETN bead inside that when wrapped in compressive tape and kinked, wont snap inside. Do you guys think that I could stick with the Al foil (but using a narrower strip) method and somehow add something flexable under the compressive rubber wrap that will resist the small radius (<3cm) kinking?

Perhaps the ratio of Al foil to rubber is too high and I would do better to use the minimum amount I could possibly get by with that will contain the delicate ETN bead and keep it in one place for long enough for me to get the first compresive wrap of PIB around it. I am thinking the thinner the foil the better and the more wraps of PIB I give the core the less vulnerable to kinking the final cord will be.

Thoughts, ideas?

Regards, Frank
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[*] posted on 24-7-2010 at 06:02


Hello Frank; it's been a few years since you've posted in various places.... welcome back.

I know you've seen a fuse machine where the weave is made below a hopper of BP and the result is a BP core inside a round braid; that's the professional method. Getting a fuse weaving machine is not cheap and setting the thing up is a serious nightmare, even for a factory with people who have worked with a weaving machine before.
Methods of making something simple generally hinge on keeping the length at a meter or two at total - max. The best I have heard of is the same technique for BP (naturally).
A woven tube "shell" is available at high-end electronics stores (this is important because it allows the thing to "breath" while holding the material) and a very sharp ended funnel needs to be found. As some material is placed within, it is compacted with compressed air from any compressor that has standard hose fittings - so again, a sharp ended little jet can fit inside and compact the powder with the compressed air. That's why you use a woven shell; to let the air release but retain the crystalline material effectively.
Air is a very effective way to compact various material & is safe. - Unless it's compacted to a great degree it will always kink too easily.

I imagine the science of this agenda would be in the construction of a real weaving machine or even understanding a method to do so. Many of the machines in use today were actually constructed well over 100 yrs ago. There is no real new technology that I'm aware of for fuse mfg. I would be very surprised if there was. The last time this subject had even arisen, someone found a fuse-weaving machine for bout $2000 but the complexity was really a turn-off as you don't know if you're getting all the correct parts (or if they function properly).

If you were really serious, the idea of understanding a round braid would be an important step in considering doing it on a high quality level.
But the manufactured hollow braid material I have seen in electronics stores would work very well for a short section and look quite professional; it would just need to be compacted with serious air (say about 150lb machine to get a good tamping).
Someone MAY post a link to a machine. They are NOT light-weight & they appear complex as all get-out.

[Edited on 24-7-2010 by quicksilver]




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[*] posted on 24-7-2010 at 06:07


Quote: Originally posted by Deceitful_Frank  
Hey guys it has been a while!

Just wondered if anyone can help with this one...

I have experimented at length with ETN and obtained great results. It will initiate another cord with a 3cm overlap, ANNM etc. you can have some SERIOUS fun with a few metres of well made 10g/m!

Thoughts, ideas?

Regards, Frank



----------
Heat shrink tubing
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gnitseretni
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[*] posted on 24-7-2010 at 07:02


I've tried loading PETN into heat shrink tubing once. I remember that it was a pain in the arse!!
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Jimbo Jones
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[*] posted on 24-7-2010 at 07:44


What about mixture based on ETN, NM and NC. Various NM % will make the consistence pliable enough to be extruded from 50 ml. syringe in the form of long, good shaped string. The NM will also ensure the high order detonation, because it’s very stable to LOD.

Instead of aluminum foil you may use a fat, long strip of paper tape (same as the duct tape, but with paper), which after the folding is covered with thin layer of rubber glue.
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franklyn
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[*] posted on 24-7-2010 at 08:03


Det Cord Post - Now locked
http://www.sciencemadness.org/talk/viewthread.php?tid=8827#p...

The Dupont TYVEK Tape links above are now extinct , use these instead

http://www2.dupont.com/Tyvek_Construction_Asia_Pacific/en_CN...
http://www2.dupont.com/Tyvek_Weatherization/en_US/products/c...
http://www2.dupont.com/Tyvek_Weatherization/en_US/products/r...
http://www2.dupont.com/Tyvek_Construction/en_IE/products/acc...

______________________________________________________________


The two methods suited to making sleeves are Maypole braiding and Knitted cord

Toy Knit cord machines are available that can produce modest lengths and one
can assess their worth in a particular application before committing to purchase
an industrial machine which can cost a few thousand dollars new. In operation
both types of machines extrude the cord down so that a nozzle very much like
a large eye dropper style turkey baster inserted in the open end of the warp
feeds the filler into it as it is being made.

Useful toys
Bond Magicord Machine ( knitting type )
http://www.bond-america.com/help/help_cc.html
http://www.allbrands.com/products/abp08057-0300.html
http://www.allbrands.com/products/abp04018-0300.html
http://www.allbrands.com/products/abp08059-0300.html
Real machines
http://www.lambkmc.com/product/15164/model-2nba-and-z-and-tb...
http://www.lambkmc.com/product/15165/model-cd-and-2-and-cd-a...


Maypole braiding machines
In the braiding process spindles of yarn (or monofilaments) are placed on
what's called a carrier. Braiding machines range in size from 8 to 144 carriers.
The carrier orbits along the circular deck of the braiding machine in a "zig-zag"
fashion on a sinusoidal track while the yarn is pulled off the spindle. Half the
carriers move in the clockwise direction, while the other half move in the
counter-clockwise direction. This, combined with the wavering motion of the
carriers weaves the warp of a braided sleeve.

Maypole Braider.gif - 100kB

Verticle deck , single head , maypole braiding machine with inverted takeup ( down )
having either 12 or 16 carriers , is what should be sought.

Both Maypole and Knit types compared
http://www.braiders.com/regknitbraiders.htm

This machine is set to feed the braided sleeve downward through the central opening.
The filler feed nozzle would be situated above it as the sleeve is formed over it and
is drawn tight like draw strings over it.

[url][/url]
[url][/url]


[Edited on 24-7-2010 by franklyn]
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quicksilver
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[*] posted on 24-7-2010 at 08:08


Wow! There you have it.
Notice that the actual mechanics (most likely) have not changed for a great length of time. The complexity is such that I deeply doubt that such a thing could be duplicated by even the most ardent home mechanic. One of the things illustrated is the customization of the gearing & the very slim likelihood of preexisting machinery to substitute for a machine built from the ground up. This is not a light-weight project....



EDIT:
One possible alternative is to learn a type of Japanese braiding called Maru-To-Kaku (sp?) which can use a wooden loom to produce to round hollow braid used in classical time-fuse. This is hand-made pyrotechnics of the "family tradition" type & also not too easy to learn but it's not impossible. The time-fuse braiding would wrap around almost any tubing of BP (or what have you) & keep it from kinking. It's not a"lost art" as it's practiced just like hand-rolled hex brick firecrackers & you have to get the hang of it.
It does use an "up-ward" direction to the hollow core braid as I think that just may be a practicality in making this stuff. It would certainly keep the tube from kinking as that's it's function.
I have the 1st part of the technique (the technique of the braid) as the 2nd part is too big to post and simply has the various tubing liners, some BP related material and modern methods.



Attachment: maru-to-kaku1.pdf (538kB)
This file has been downloaded 1029 times


I had a look at the real thing (commercial: Austin Powder Sales, orange in color) and it had a tube of what I would bet is Teflon/PTFE to bind the core. With some form of wrapping (previously discussed) on the surface, it's fairly tough to kink. It's "bend-ability" is about 1cm (where it will NOT kink) & a knot is possible provided you don't pull it taught; a knot with a double half-hitch, does not kink at all not matter how hard you tug. So I think the real issue is the core liner. I have NO idea where to get something like it. It comes in various widths (measured by weight in gr. per foot) but the walls are quite thin (0,25mm or finer) and it really does look & feel like Teflon. The reason I believe it's PTFE is that it has a slick feel that seems to "push" the core keeping it from kinking.

[Edited on 24-7-2010 by quicksilver]




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[*] posted on 24-7-2010 at 08:52
In the beginning....


BICKFORD'S SAFETY-FUSE
By SIR GEORGE J. SMITH
[GWS was a director of the Bickford,
Smith and Co., Limited. Tuckingmill,
Cornwall England. /djh/]

THE frequent accidents resulting from the use of explosives in tin and copper
mining, chiefly owing to the uncertain duration of the time between the lighting of
the rush or quill and the exploding of the charge, led Mr. William Bickford, of
Tuckingmill, in or about 1830, to turn his thoughts towards the invention of some
method whereby blasting operations could be conducted with the minimum of
risk to the miner. Mr. Bickford's motives were purely philanthropic; it remained for
his successors to turn his invention into an extensive and legitimate commercial
enterprise.

On the 6th September, 1831, Mr. Bickford took out his first Patent (No. 6159) for
the Miner's Safety-Fuse. His object was to provide a protected core of powder,
thin and continuous, along which the fire might travel slowly at a uniform and
determinate rate of speed. This result he obtained by causing a number of jute
threads, passed through an orifice and stretched by means of a weight attached
to their extremities, to rotate slowly while, at the same time, a small current of
fine powder fell into the tube thus formed, and was retained therein as a slender
core. To use his own words in the specification of his process:

" I embrace in the centre of my fuse, in a continuous line throughout its whole
length, a small portion, or compressed cylinder, or rod of gunpowder, or other
proper combustible matter, prepared, in the usual pyrotechnical manner of
fire-work for the discharging of ordnance; and which fuse, so prepared, I
afterwards more effectually secure and defend by a covering of strong twine
made of similar material, and wound [113] thereon, at nearly right angles to the
former twist, by the operation which I call 'countering,' hereinafter described: and
I then immerse them in a bath of heated varnish, and add to them afterwards a
coat of whiting, bran, or other suitable powdery substance, to prevent them from
sticking together or to the fingers of those who handle them; and I thereby also
defend them from wet or moisture or other deterioration, and I cut off the same
fuse in such lengths as occasion may require for use: each of these lengths
constituting, when so cut off, a fuse for blasting of rocks and mining, and I use
them either under water or on land, in quarries of stone and mines for detaching
portions of rocks, or stone, or mine, as occasion may require, in the manner long
practised by, and well known to, miners and blasters of rocks."

&c., &c.

The Rise and Progress of the British Explosives Industry
Published under the auspices of the:—
VIIth International Congress of Applied Chemistry
E A Brayley Hodgetts editor
Whittaker and Co. London 1909
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gnitseretni
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[*] posted on 24-7-2010 at 08:52


Here's a homemade machine for making fuse:

http://www.truetex.com/visco.htm

Maybe it could be used for making det cord?
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franklyn
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[*] posted on 24-7-2010 at 09:04


Quote: Originally posted by gnitseretni  
Here's a homemade machine for making fuse:

http://www.truetex.com/visco.htm

Maybe it could be used for making det cord?


Definitely ! that's really neat.

The cord shown is made with string or twine , not the best choice.

Lacing cord is flat and forms a tight warp.
http://www.google.com/search?hl=en&source=hp&q=Lacin...


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The hard way _

http://www.englisch.kumihimo.de/html/history.html

Maru_Dai_Diagram.gif - 6kB

[Edited on 24-7-2010 by franklyn]
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pjig
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[*] posted on 25-7-2010 at 10:03


What about using 3/16 poly tube, and packing it with a core of etn? Seal it with a vacuum, then wax or glue the end closed.

I have seen a great patent using NM and al or NM and micro-balloons to sensitize it. I believe that the were able to carry det with as small as a 1/8"id. over several hundred feet.
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[*] posted on 25-7-2010 at 20:08


I think the problem with shrink tubing and the like is getting the ETN uniformly
into the tubing.

How about absorbing molten ETN (or a saturated acetone ETN solution) into a
loosely woven cotton cord, letting it cool or dry and then placing that into
shrink tubing and shrinking it. (or you could wrap it with treads). The inner
cotton cord would also help stop gaps from forming when you bent it.

[Edited on 26-7-2010 by gregxy]
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Deceitful_Frank
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[*] posted on 26-7-2010 at 11:34


Quote: Originally posted by gregxy  
I think the problem with shrink tubing and the like is getting the ETN uniformly
into the tubing.

How about absorbing molten ETN (or a saturated acetone ETN solution) into a
loosely woven cotton cord, letting it cool or dry and then placing that into
shrink tubing and shrinking it. (or you could wrap it with treads). The inner
cotton cord would also help stop gaps from forming when you bent it.

[Edited on 26-7-2010 by gregxy]


I have tried a similar method before. loading a hot saturated solution of ETN in ethanol into a syringe and then evenly ditributing it throughout a 1m length of toilet tissue. Tissue absorbs the solution and as it cools, the ETN quickly precipitates and the crystals are trapped within the fibres. The ethanol will then evaporate within a few minutes and you have something very durable that you can wrap at will with your shrink tubing, thread or PIB tape.

There is one major snag though! In order to get all the Ethanol that would contain those 10 grams of ETN for the metre of cord absorbed you really do need 2-3 grams of tissue paper and this will bring the inert content of the central core of the det cord will up to the 20% mark. this degree of inerts may well shoot in a lump of plastique but in a length of detcord whose core is a mere 5mm across... not a chance!

Perhaps if we found a tissue that was absorbant enough that a gram of it could hold the 10ml or so of solution we might get a cap sensitve product but it seems to me unlikely.

How about if we nitrated the tissue as well?

Then even if it accounted for 20% of the mass of the core at least it wouldn't be totally inert. NC does tend to have a rougher feel than the un-nitrated cellulose. Would it be less absorbant? Plus we need to be sure that the NC would not be dissolved by the saturated solution of ETN in the hot ethanol.

[Edited on 26-7-2010 by Deceitful_Frank]

[Edited on 26-7-2010 by Deceitful_Frank]
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franklyn
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[*] posted on 26-7-2010 at 18:25


Quote = Deceitful_Frank
" How about if we nitrated the tissue as well ? "

My thought exactly , nitration of cellulose to produce " flash paper "
is as simple as it gets. A legacy of experience with this material exists
since it was among the very first commercial high explosives.
Gun cotton was discovered by Braconnot (France,1833) and patented
by Schonbein (1846) , the year Sobrero synthesized glyceryl trinitrate.
Many compositions are based on the two ingredients of nitrate ester
and nitrocellulose.
http://en.wikipedia.org/wiki/Gelignite
http://en.wikipedia.org/wiki/Ballistite
http://en.wikipedia.org/wiki/Cordite

The question at hand is the cord produced with long term storage in mind
or for immediate use. If the use is only to transmit a detonation wave to
several charges , it doesn't really need to be fast.
Gun cotton that has been washed , neutralized and spindled into twine
then soaked in a hot saturated solution of ammonium nitrate and vacuum
dried , finally covered by a cloth sleeve , can be sensitized in the field by
drenching with Nitromethane.
Sleeved cord.gif - 10kB
If you want pointers on how this is done make friends with someone
who is good with a sewing machine.

It bears emphasizing that producing cord from tape is the simplest means
available as well as cheapest and much stronger than other improvisations.
Because the tape is impermeable it cannot be soaked as described above.
http://www.sciencemadness.org/talk/viewthread.php?tid=8827#p...

.

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pjig
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[*] posted on 26-7-2010 at 18:38


Huh.. you just might be onto something here... I think guncotton its self could serve as a det cord inner material....
While on that thought, ETN or guncotton could be pressed into 3' sections of say 3'16 flexible pvc clear tube, to make det-cord.
One could use a 3/16 wood dowel and pack the explosive substance into the tube. To join the sections of tube to get one long strand, one could tape them together, or use a larger dia. tube as a sleeve to join the two.
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[*] posted on 27-7-2010 at 06:17


Quote: Originally posted by Deceitful_Frank  

How about if we nitrated the tissue as well?



I would be remiss if I failed to note that unless NC is
carefully neutralized there is ever the possibility of spontaneous
combustion. In the early days several battleships were destroyed
by fires/explosions caused by unstable NC. Remember the
Cleveland clinic X-ray film fire.
http://images.ulib.csuohio.edu/u?/general,280

Faversham explosion, &c.,&c.

Boiling for a week or so with periodic changes of water works
or you could try urea. (See attached)




Attachment: NC Stability.txt (6kB)
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Attachment: NC Hall-Schonbein.txt (6kB)
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[*] posted on 27-7-2010 at 06:27


ErTeN would definately work in a plastic tube, I am not sure about the Guncotton though. It could be just my perception but Guncotton would be very difficult to work with this way. Guncotton is also expensive and difficult to manufacture in large quantities, relatively(I think). Guncotton can also not go, or go low order if conditions aren't right either I think(correct me if I am wrong).

Your idea of the flexible plastic tube is a good one I think. The first time I saw this was in a post on Rogue Sci, I think it was Boomer maybe, discussing loading ETN(I think), into plastic(polyethylene?) aquarium tubing. He was using a long, flexible, good quality wooden dowl(of appropriate diameter) to pack it in, in increments. I am not sure how he was feeding the explosive in(or I can't remember), but it seemed workable for sure. This would work for short lengths anyway, long lengths is another story. I am going to have to try this, I have been meaning to for awhile.

edit: The Wizard got one in ahead of me. I have used urea in the final wash water with Guncotton because it is what I have and it seems to do the trick. I just read recently that they don't use urea with smokeless powder because as it does its thing it gives off small gas bubbles, and these small gas bubbles are a big problem in the smokeless power(irregular burn rates, etc). Alittle off topic. On topic, the Guncotton neutralization would also add to the difficulties for the amatuer in dealing with this material in that capacity, I agree.


[Edited on 27-7-2010 by Hennig Brand]
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[*] posted on 27-7-2010 at 09:37


One big advantage of ETN is that it can be melted.

How about :

1. Fill a syringe with ETN.
2. Firmly attach the syringe to a length of plastic tubing,
The following site has every possible type
http://www.mcmaster.com/#tubing/=8589xu
a tube with 1/8" id should give 10g/M ETN.
3. Immerse the whole in water hot enough to melt the ETN
but leave the open end of the tube above the water
4. Inject the ETN into the tube, with care it should be
possible to displace all of the air.
5. Remove from the hot water and let it cool

If possible it would be best pressurize the liquid ETN enough
to stretch the tubing during step 4. This would compensate
for shrinkage upon cooling.

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[*] posted on 27-7-2010 at 09:40


This is a good topic :D

On the small dia fish tank tubing idea, here is a thought for charging your det cord.

What about using a dbsp and charging the tube via a hopper. Then on site pumping enough nitromethane into the filled tube to saturate the dbsp. Upon swelling of the dbsp, the desity would rise and your cord should have a fairly high VOD that would sustain det through even a smaller dia tube than most explosives.
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[*] posted on 27-7-2010 at 09:52


Filling tubes is only practical for short lengths if the explosive is solid.
Joining short lengths together requires that continuity of the explosive
be maintained or else the detonation wave will stop where it is joined.
This is why det cord is extended by overlapping the ends to assure
continuity of explosion. At 75 cents per foot , shrink tubing is quite
expensive and practically without any tensile strength.
Tubing containing a liquid explosive may work , providing there are no
kinks or large voids. Small bubbles have the detraction that it serves
to sensitize the explosive making it susceptible to initiation from impact


Guncotton alone cannot serve the purpose but it can serve as the base ingredient
of the explosive. To produce something approximate to gelatin dynamite as a cord ,
a nitrate ester will need to be soaked up in the cord to process into the desired
product. This can be unnerving to do and is not without some risk. Whether the
resulting colloid can be sufficiently insensitive for safe application is unknown by me ,
this is undocumented proprietary know how of the original manufuacturers.
Winding cotton cordage for composition with another explosive is worth examining.
It's a simple matter to nitrate cotton thread or yarn and then use that to produce
cord. http://en.wikipedia.org/wiki/Nitrocellulose - It is necessary to do this before
it is wound into cord so that remnant acidity can be neutralized.
Lline can be secured at one end and twisted from the other end by using an attached
electric drill or screwdriver. Placing in parallel , three lines twisted the same way ,
say counterclockwise , they twist together naturally into a cord clockwise.
Full instruction in the Boy Scout manual. Attachment: BoyScoutRopemaking.pdf (450kB)
This file has been downloaded 715 times
Video how to => http://www.youtube.com/watch?v=RMy7JJdS9DY
http://www.youtube.com/watch?v=eIh3013NT0g
A usful site on cordage and ropes
http://groups.yahoo.com/group/ropemaking
Rope making videos - see the other links
http://www.youtube.com/watch?v=1VKHNSdpLyg
Braiding Machines - see the other links
http://www.youtube.com/watch?v=Iy9Q8Yuu6OQ
http://www.youtube.com/watch?v=dER8DM3aYqk
The real stuff
http://www.dynonobel.com/NR/rdonlyres/209B7E9F-6C15-40EF-B67...

Light speed detonation velocity
Optic Fiber Laser Detonator
http://www.osti.gov/bridge/servlets/purl/219536-Awf457/webvi...

.

[Edited on 27-7-2010 by franklyn]
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[*] posted on 28-7-2010 at 06:12


I have access to some equipment and just for experiment's sake I was fooling around and looked at what it would take to fill a tube of moderate length (9ft) with an inert material. Using an "aquarium bubblier" attached to an end of some vinyl tubing I rigged a thin ended funnel and used a air compressor. The "bubblier" allowed the compression to take place with a element of compression bleed-off and the inert I used with diatomasius earth. Several yards of compressed powder presented no problem. As the length got longer, the bleed off of compressed air presented no difficulty IF the bleed-off existed. There IS a bit of "technique" to filling the tube. One needs to start off gently so as to get several inches filled before a full level of compression is used.

What challenges did exist were the powder consistency itself. Even filter diatoms were still too rough. PETN are typically needles, ETN would be platelets; these shapes don't lend themselves to packing! A great deal of shaving was in order OR a method of maintaining low crystal size / density.
The interior of the tube presents another agenda. If Nonel tubing is examined, there is a smattering of powder through out it's length - some of that material is aluminum! This could be ideal material to dry lubricate the walls of the tube and fine enough to adhere to the walls forming a drag-free surface.
Where this needs further examination is [that by making] the filler material becomes finer, the compacting element shuts down the flow of air and the result is that a few yards may be packed quite tightly until the compact mass allows little to no flow of air. Thee are various physical techniques to deal with such as holding the ends while compacting the powder as the force is enough to shoot off the ends, the funnel, etc unless care is taken. To really get this to be a tightly packed item, it needs some serious pressure.

The kinking problem could be dealt with by picking a tubing that gives some resistance to kinking and sheathing that with some supporting tube like a tight round braid. The kinking issue is the less problematic one. It's important to remember that even relatively small tubing can hold as much as 4+ grams per foot. - From a commercial perspective, that's quite large! For effective use the tubing core could certainly be quite thin. This is a very workable exercise. The various stumbling blocks COULD be over come with careful experimentation.




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[*] posted on 28-7-2010 at 08:50
Shock tube


Just another thought on transferring of detonation waves... using the same idea with the small dia tube( like the clear stuff they use for swamp coolers"evaporative coolers") it is around 3/16 " and fairly sturdy.

Could one take a thin liquid glue and pour it through the tube, drain it completely, then let it tack up. Next using a compressor they could blow a fine dusting of high grade explosive like pent+Aluminium, through the tube. And there you have it "shock tube".. This could be used to transfer Det over a long distance, and being easy to make long pieces at a time.
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[*] posted on 28-7-2010 at 10:57


Shock tube needs an initiator that has to fit the end of the tube. Some of them look like bridge-wire set-ups without the energetic material. They are then zapped with a CD device. What's used in Nonel is HMX and Al in a SUPER fine coating and it's really thin: just coats the inside. You can barely see it. You see, if you use more than a super small amount it won't travel: it will pop right there.
Imagine getting about a grain of 2 micron (or finer) explosive w/ Al and blowing it through the tube. What would stick to the inside would be what's appropriate.....it's really a tiny amount. I've seen it work and it's pretty clever. It's possible that less than a grain is utilized for a meter or more: it's that fine. The initiation needs to be fairly potent to start the travel of the shock tube. As it moves, it builds: just sightly until at the termination point it's fairly potent. But it can't start off that way. The physics of the thing is pretty impressive.



edit:


It's SO fine that if you saw a picture or held a piece up to the light you would have a hard time seeing the actual explosive: it's that minute.

Some time back there was a LONG thread about altering the composition of various explosive's crystal formats. Basically, to reduce them to a finer grain or particulate. There ARE ways it can be done via the re-crystallization or initial synthesis. But it becomes more important as the applications widen in scope.

[Edited on 28-7-2010 by quicksilver]




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[*] posted on 28-7-2010 at 23:39


Quote: Originally posted by quicksilver  

ETN would be platelets; these shapes don't lend themselves to packing! A great deal of shaving was in order OR a method of maintaining low crystal size / density.


Just shooting off at a brief tangent, on the subject of crystal shaving, I would just like to pick your brain a little.

I know you also favour ETN. Do you have much experience in shaving or manipulating crystal shapes to give a higher bulk density and less need for inerts to fill the voids? I would love to one day be able to produce a lump of workable, usable, handlable plastique with no volatiles and one active ingredient... ETN makng up 85%. >=92% is possible with PETN so surely this isn't beyond the realms or possibilty?

Using unaltered recrystalized ETN you really need minimum 25-30% inerts to fill those voids and hold it all together. Then you need a big ass cap, strong confinement and you can forget small critical diameters!

Sure I can add 15g of NM to 85g or ETN and deliver some serious hurt. A suspension of ETN in a NM/ETN syrup! but this is messy and unless sealed airtight remains usable for just minutes.

I know nitro-genes has had much success manipulatiung far from helpful PETN needles. Making plastique that is short of platisizer to give a firm feel and rolling it on a hard surface to round off the crystal edges and provide the extra ultra fine fraction of PETN within the mix. I guess this fraction fills in the gaps between the larger crystals to give what would have been a higher bulk density of the active ingredient.

Also IIRC he was had success grinding wet PETN with a pestle and mortar. breaking up the needles just to the point where they are approximately cubic and then adding a small fraction of VERY finely ground PETN. I think he managed to produce a quantity of workable plastique in the region of 1.6g/cc. To be able to deliver such energy into a small space with a material that is safe to handle with bare hands, no volatiles or mess is most impressive.

I believe that ETN is so powerful and easy to make that the extra effort for PETN albeit with 6-7%? extra density, a little more safety and less headaches from skin contact is hardly worth the ENORMOUS increase in effert and expense.

I obtained a substantial quantity of PE at GREAT difficulty, nitrated a small amount using mixed acids (I've neither time nor motive to seriously consider distillation of HONO2)... Terrible yeild. Of course I was impressed with its power but to be fair I would sooner expend half the effort and get twice the amount of ETN for my trouble!

I would like to try some crystal shaving with ETN. I am aware that it is some 30% more sensitive to initiation... and friction? When I recrystalize from MeOH I get short needles. When I use EtOH I get platelets (well 90% EtOH with approx 5% MeOH and 5% gasoline! we call this methylated spirit in the UK and it is used for cleaning tools and as a burner fuel. Pure 95.5% EtOH is EXTREMELY expensive and difficult to abtain due to taxes and safetly law)

If I was to put 1 gram of ETN in to a mortar with say 3 grams of water and grind with a pestle, which crystal shape do you think would give a better bulk density after grinding plus more likely leave my sight, hearing and fingertips intact?

Everything that I have learned about ETN tells me that even a 1:2 ratio with water is TOTALLY safe to grind and near IMPOSSIBLE to detonate but I guess I just need reassurance!

What do you think?

[Edited on 29-7-2010 by Deceitful_Frank]
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[*] posted on 29-7-2010 at 05:12


Well, shaving crystals of ETN wouldn't be accomplished by direct grinding; remember they are flat. And, yes, I think it's too dangerous also. Even if you put an amount in a plastic bag and gently manipulated them for quite awhile, they wouldn't shave to the degree you'd want. They are flat platelets & as such they stack like cards; too difficult to have their edge's contact.

You would need to accomplish this in restructuring the crystal. Using near to anhydrous ethanol or methanol, you would dissolve the ETN in warn (50-60C) alcohol and crash that out into near to frozen water. The crystal shape would not form with any rigidity and you would have very irregular grains that would be quite ridged (similar to table salt but non-cubical). Then - those granular particles would shave fairly fast.

Yea; you wouldn't want to grind them...even in water. It's possible to get hurt. Plus it wouldn't work. - PETN shaves because the needles are thin, small, & very brittle. Nitroguanadine also have needles but they are long, fixable, & thick and buddy; there is no easy way to shave that crap down at all. I actually don't know what they do to put that in triple based powder....it's very difficult to work with. Where as I have seen PETN that was near to powder as one could want.

Many people get poor yields with PETN and wonder what they did wrong but they didn't know that in industry, companies do NOT use simple PE: they use very high-end reagent grade material. If a person attempt to nitrate the PE that's used for the paint and vinyl industry, they will end up with a looser yield if they are lucky or virtually nothing if they do not work the synthesis correctly. It's possible you got some tech-grade, commercial PE. The fact that you got a yield show that you did the necessary work, but th likelihood was that someone had tech-grade material. It really DOES have to be high quality for PETN to yield high. That's one of the major reasons why PETN costs more than RDX.



[Edited on 29-7-2010 by quicksilver]




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