EatsKewls
holmes1880 (banned)
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SDT/DDT conceptual research and patents.
I would like to bring to primary-complacent readers a very good paper that finally surfaced on the net. First part of this research project used CP
(aka 2-~5-
cyanotetrazolato pentammine cobalt ~III perchlorate) to study DDT and SDT in granular secondary columns. Google around and you might find it. CP is
actually quite similar to ETN and MHN in its sensitivity and DDT behavior.
http://www.smf.phy.cam.ac.uk/fsp/Publications/Energetics%20p...
This part of the research paper addresses PETN. As interesting of a research as this was it was primarily aimed at study of how DDT occurs in these
columnar secondary grains. The process is quite odd, in simple terms there is an initial slow ignition, which then travels down the column creating
convective hot spots head of it. Simultaneously, the pressure builds up which leads to a compaction wave that is traveling ahead of the the convective
burning. Finally, at some stage a shockwave compacts the material ahead to 100% TMD at which point the detonation occurs. Very confusing, yes. I
believe the idea is that the plug is moving so fast and getting compacted more and more, that is also accompanied by increase in temperature, which
eventually leads to detonation.
Regardless, from there alone it is easy to understand why both lateral and vertical confinements are essential in such systems. The paper notes the
significance of that, without mentioning any specific figures. But they have used good deal of confinement since they were using steel container and
had metal and copper plugs where the reaction zone started and then a little steel piston that eventually rammed itself into the witness plate (I
assume they measured detonation by the dent the piston made on the brass plate).
As a side note, most non primary designs used in the industry work on a somewhat different principle. The first of Nonel non primary patents US Patent
4727808 work on a small little pipe bomb with small apertures in top and bottom that is sitting on the base charge. The "initiator pipe bomb" is
usually built of steel, while the rest of the detonator body is aluminum, typically. To manufacture such little units you'd need one again that bullet
swaging tool or might need to get a drill station, so you can drill out cores in two rods of complementing diameters which then fit inside of one
another very snugly. Some easier means could be improvised depending on your imagination. They even got this method to work quite well with RDX, which
is pretty ridiculous. I've slept on this patent, but maybe will get inspired to build something like this just for amusement's sake.
What that or other patents won't admit, though, is how damn hard it is to light that PETN using fuse ignition( I don't consider shock tube a "fuse").
[Edited on 7-3-2012 by EatsKewls]
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EatsKewls
holmes1880 (banned)
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Sounds like the Chinese knew what they were doing, I got the 200mg aluminum embodied initiator unit to detonate the intermediary base of 200mg
1.0g/cc. I had to opt out for aluminum initiator unit and steel outside capsule, as it was quicker to shape the aluminum tubing, than it would have
been with steel.
I am surprised that it worked so well, because this initiator unit is nothing more than an oversized bullet primer. I am almost certain the 220mg
charge at 25mm length could not detonate on its own, so it was only a violent deflagration. Nonetheless, it was sufficient to initiate a medium
density output charge. After multiple tests, it is easy to distinguish a detonation by the metal fragmentation, blackened surfaces, and obviously the
damage to the witness brass casing.
Another patent to examine would be Patent 6736068, but it will be more challenging and time consuming to construct. Obviously, there are several more
NPED patents that can be worked with in amateur conditions, so there is no need for noobish experiments with copper themite and aluminum foils.
I am using different devices that do not utilize steel and are easier and less time consuming to build. With that said, if you aren't capable of
coming up with your own designs, make do with what is already out there. Just make sure to standardize the process to produce consistent parts in your
production process, so there is no significant variability in the performance of those caps.
[Edited on 7-3-2012 by EatsKewls]
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EatsKewls
holmes1880 (banned)
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The God-syndromed EatsKewls has yet another design. This one I've based on various works, some from my research, other elements were incorporated from
Los Alamos research on PETN. A very unique design, utilizing no steel, which is very rare in DDT initiators. Moreover, the base charge encapsulation
is a mere 0.35mm 6061 aluminum (maybe 6061-T6, but no big difference). I've tested 6 or 7 of this type of design with very excellent results and
initiation of 6g stinger charges.
Now, this is a 3rd design of DDT initiators that are professionally adaptable, albeit, I need to invest some time in a more standard ignition of the
secondary. So, Rosco's propaganda on primaries being a good, reliable initiation is once again busted. 
I've tried to look up the data on what percentage non primary initiators take up in the industry, but Nonel isn't posting those figures and I'm not
sure what would be a reliable source. Nonetheless, I think non-primary initiators are eliminating the more toxic and static-unfriendly initiators used
in the past (aka azides).
Point being, non primary initiators can be made very reliable even in amateur conditions and will eventually become an absolute industry standard.
Amen!
---------------------------------------------------------------------------
P.S. Rosco, I too have been victimized as SB15 made a hate blog against me too! LOL The hyena collected my quotes as far as 2 years ago. Talk about losers these days....
http://explosives.freewebspace.com/
And another look at the design:
http://oi39.tinypic.com/ifo0tw.jpg
[Edited on 21-3-2012 by EatsKewls]
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Rosco Bodine
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You are reinventing the wheel, outstanding, another round one. And look it's not just round, but positively cylindrical. Like I have said before and
also posted a few patents concerning such devices, NPED's are the same or closely the same thing as "safety detonators" (which is a dubious highly
qualified name) and have been around for a very very long time. It is not really anything new. What experiments I have done has not been intended to
remake a commercially available safety detonator of whatever variety, but I have a loading press and dies and could do that if I wanted. Generally if
I need to test something, it is a materials test or a process test. For a materials test, the test is usually done in a poly test tube (believe it or
not, testing using a what? a test tube) ....so the way it goes is usually as simple as... place weighed increments of base charge in test tube and
firmly press, add weighed increments of initiator and lightly press, add weighed increment of flash igniter and leave loose, insert firing squib or
fuse coupling sleeve ...that's it. And what I would do there is not anything new in the art either, which is honestly more in the way of materials
testing than configuration or device testing. It is the energetic materials which are my interest more than the devices which can be made from them.
And no it is not propaganda that primaries provide good safe reliable initiation, as billions of units have established is a fact. A goat constitutes
a self-powered lawn mower and has been around longer than the gasoline operated type, and may in some situations be safer. Does that mean a goat is
"better" or that the mower that runs on gas is invalidated?
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SB15
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For the record, while I'd love to take credit for this brilliant work, I had nothing to do with its creation. You'll have to ask around to find out
which one of the dozens of enemies you've made over the last 2 years is responsible for posting it. I'm sure you'll figure it out eventually, holmes.
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EatsKewls
holmes1880 (banned)
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Rosco, can you trace back to those 'safety detonators', I would like to read more on them. It isn't those HEP(high energy pyrotechnics...aka flash
powders) detonators? Those are terrible.
| Quote: | | . For a materials test, the test is usually done in a poly test tube (believe it or not, testing using a what? a test tube) ....so the way it goes is
usually as simple as... place weighed increments of base charge in test tube and firmly press, add weighed increments of initiator and lightly press,
add weighed increment of flash igniter and leave loose, insert firing squib or fuse coupling sleeve ...that's it. |
Ok, so you just make the most primitive cap 5 minutes can buy. An IED cap, of sorts. It isn't something you want to carry on you while going to the
test your material of interest. I wouldn't dare to store them either, if you ask me.
If you do frequent energetics testing or even out of recreational interest, it is worthwhile to have a very safe initiation system. This is why
universities mostly use EBW systems for their tests. EBW, however, is impractical and inconvenient for both industry and amateur use. I guess for me
it is the device vs. the material. Materials are already there, but not the devices.
[Edited on 21-3-2012 by EatsKewls]
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Rosco Bodine
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The references would be posted years ago and the patent references have no order or keyword that I can recall, but several have been posted. It was
never really intriguing for me because the devices required precison manufacture techniques, progressive density loadings, or blends of materials
cocrystallized, special igniter methods ....very finicky troublesome kind of effort to make a reasonably reliable device ...and then what was the
result was still not as reliable as a discrete dedicated increment conventional firing train. When dozens or more were tested....there wasn't the same
absolute reliability, but an unacceptable misfire rate, not meaning the devices didn't light off, but they only low ordered or gave a defective output
and produced inferior unacceptable plates in those cases. I do recall they had reliability issues.
What I rarely do but have done is science experiments, not manufacture IED's, but what you are doing is something else evidently, more like a
"commercial product development" or prototyping. And that sort of thing is not really the focus of discussion here, although we do share ideas on
such things, there is kind of a line we don't cross, because from what I understand would be the illegality of "engaging in the business of
manufacture" aspect which seems to be your interest. So what is "primitive" or not depends entirely on what you are doing and what is your purpose.
Did it go right past you when I said I have a loading press and dies and can load metallics if I want. I have no reason but if I ever needed to go
that route I could, but have no legitimate need for doing so. If that is primitive ..okay yeah.. I'm a primitive having peace of mind for limiting
myself to science experiments involving materials testing in test tubes. They get the job done for my purposes for whatever may be the science
experiment I may want to do.
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EatsKewls
holmes1880 (banned)
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| Quote: | | [qoute]required precison manufacture techniques, progressive density loadings, or blends of materials cocrystallized, special igniter methods ....very
finicky troublesome kind of effort to make a reasonably reliable device |
That's some terrible patent that I've not seen. I do still have a hurdle in reliable ignition of secondaries. I do not know the exact difference in
ignition behavior of ETN vs. PETN, but ETN is very troublesome to ignite from the top-only ignition source, as the usual configuration of train
ignition utilizes. ETN behaves quite sporadically, igniting in short spurts, but if not sufficient quantity has been ignited at once, it will go out.
Porosity plays a big role as well, which obviously allows for a better ignition and flame front being able to penetrate the column better. Confinement
may be critical too, if employing fuse ignition.
The way that has been dealt with in some patents was with lead oxide/silicon mixtures, red lead (lead tetraoxide) again with silicon, then some other
had 70:30 PETN/lead picrate/potassium perchlorate (I was under impression lead picrate was a primary, though).
As for me that's the most troublesome part of these designs. Even dextrinated lead azide will give you fits igniting reliably and requires a more
sensitive compound on top.
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woelen
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Thread Split
22-3-2012 at 23:18 |
woelen
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I split the thread and everything after the split is moved to detritus. Please stop flaming and keep further posts to the subject of this thread.
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EatsKewls
holmes1880 (banned)
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I have had a good deal of success with thermite ignition, using a less stoichiometric, heavier fuel mixes of MnO2 thermite. Fuel heavy mixes of CuO
thermite could also work nicely, and they actually do not bomb unlike the oxidizer rich traditional mix.
Thermite is extremely effective at igniting high density secondary columns from top-only contact. The incredible thermal shock, as I have believed in
the past and most research suggests, shortens the detonation column to a very convenient lengths, given that one is to use appropriate confinement
means.
There is an issue with thermite ignition means, as I am getting about 3-3.5 second delay from my 4 step ignition train. The entire ignition train is
only 10mm long, but it is very densely pressed, which slows the burn rate. Electric ignition would yield probably 1-1.5 second delay, but that's still
substantial. Perhaps using a more violent bismuth oxide/read lead with silicon would be preferable, but I'm too unmotivated to invest into that as of
now. In the future.
Here is a video of the ignition unit that is housed in 20mm aluminum tubing. Once thermite ignited the aluminum tubing sets on fire and crumbles. I've
tested about a dozen of those little units with very positive results.
http://www.youtube.com/watch?v=6awFDVhy5Fk
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