Making your own detcord

[steve smith]

Anyone made a good quality length of this stuff? I am talking about a length that has the consistency, and the quality of Commercial grade. I don't plan on making flame balls, i plan on using the cord for measurement purposes. More specifically, for the Dautriche method IIRC.


Thank you for ALL, and ANY ideas out there.


Steve

[vulture]

Being the one to blame for the creation of this thread, I might aswell help out. ;)

The main problem would be to get a consistent density over the whole length of the cord. Pressing is going to be tricky and not very effective, possibly dangerous too.

I would try filling the tube with a supersaturated slurry of your explosive and allowing the solvent to evaporate. The principle behind this would be that crystallization from a solvent should produce crystals of uniform density.

[EP]

One idea I've heard (but not tried personally) is to use MEKP. Because it is a liquid, you will have a consistent density throughout the tubing as long as it's filled all the way so the MEKP doesn't just pour around and drain out of the high points when it's set up.

[steve smith]

Commericailly made detcord is wrapped with a fiberous material. I have thought about using some sort of plastic for the casign, but the cord would not dry out, nor could you get the proper lengths.

Anyone ever made blackmatch before? How abotu making a blackmatch like machine, which feeds cotton through a slurry mix. The amount of mix can be regulated by pulling the sting through a small pipe, takign off excess, fillign in holes. Before this cotton dries out, maybe pull the string through some sort fiberous (either man made or natural) slieve. Let dry, then pull the whole shebange through a plastic, HDPE like pipe. All of which are eaasily found. Cheap and easy.

Military Det cord is made like this:
Polyethylene Coating
Rayon layer
Asphalt Layer
Seamless Cotton Tube
Explosive (PETN)

I would like to try and HMTD mix, one could alyways leae the cord inthe freezer/fridge for storage. I would be worried about cracking/rubbing/initiatio, in that order

Steve

[s25]

I have heard of putting a explosive such as AP into shoe lacer and that was supposed to be okay but i cannot say i have tryed it myself.And if you made the AP moist with acetone and or another fast evaporating solvent you could pack it in a little but i believe this would cause the detcord to expolode rather violently i would though

[Jetex Kid]

The Dautriche method requires that the detonation velocity of one explosive be known, and this depends on diameter, temperature, density and particle size.

(Though this is technically true, it’s largely irrelevant here because fluffy PETN will propagate at 0.4 mm (.016 inch) diameter, and even in diameters as small as det cord, PETN detonation will approach its maximum possible rate.)

Still, there exist distinct detonation regimes, and in the case of nitroglycerin there are at least three distinct, stable, Vd’s, depending on initiation conditions. The fact that PETN detonates does not necessarily imply a particular velocity, as far as I know.

Actually Steve, since you like computers, I’m trying to sell you a data acquisition card. For about $100 you can measure independently of diameter, temperature, density and particle size, to determine the true Dv of the explosive in question. (Which of course depends on diameter, temperature, density and particle size).

Actually, if you understand computers a lot better than I, you could probably write a program for any megahertz-frequency i/o card.

[Microtek]

I have considered several principles for making a detonating fuse, some of which were unpractical, but most of which were workable:

1)
-Purchase some cotton yarn ( sometimes used for sowing up stuffed food ). It should be fairly light and not too tightly spun.
-Nitrate it as you would cotton wool and wash thoroughly.
-Use it to suck up NG or EGDN, optionally with dissolved MHN, and warm it up to make it gelatinize.
-It can now be wrapped in tape or other protective coating such as liquid latex if desired.

2)
Liquid explosive in a hose.
There is a patent about using sensitized NM in 3 mm diameter hoses. The NM can be gelled to prevent spills when cutting the cord. The NM can be sensitized with powdered balsa wood.
NG could obviously also be used, but in thin hoses there would be the risk of low order detonations. NM does not exhibit this behaviour. I was thinking that a mix of NM and NG might be a good compromise between sensitivity, safety and performance.

3)
Extruded PBX.
-An ordinary plastique based on PETN or RDX with PIB(self-amalgamating tape ) or blue-tack binder is made by dissolving PIB/blue-tack binder and oil in gasoline and mixing in the PETN.
- Before the plastique is completely dry, it is packed into a syringe, the piston is rammed in, and the plastique is extruded in a long thin cord.
- It will be very fragile until the solvent has completely evaporated so it should be left alone.
- Once dry it should be wrapped in tape or coated with liquid latex for strength. ( I'v tested this and it works beautifully, though it requires quite a powerful detonator )

This can also be done with other types of binder, such as silicone diluted with ethyl acetate, or liquid latex can be used directly. If latex is used as a binder, a little lubricant such as oil or maybe glycerine ( or soap ) should be added or the PBX will stick to the syringe.

4)
Solvent free slurry.
- The oven is set at 50 C and a syringe and a length of thin hose is placed inside.
- MHN is extremely soluble in warm NG, EGDN or NM ( especially NM, but the nitric esters may be better for this purpose ), so one of them, lets say NG, is warmed to ca 50 C, and as much MHN as will dissolve is added. It may be better to add even more, so that an actual slurry is made.
- The slurry or solution is sucked up into the warm syringe and extruded into the warm hose. Then, the hose is removed from the oven and cooled.
This makes much of the MHN precipitate from the solution, forming a plastic mass along with the rest of the solution.

The problem with these is that they are so very loud. I have considered using the extruded PBX method with lesser explosives but haven't really had any successes yet.

There is one more that I have considered ( from a patent ):
Explosive gas mixtures.
- Two syringes ( or other containers ) are filled with gas; one with oxygen ( from H2O2 decomposition ) and one with a reducing gas such as C2H2, H2, propane, butane, etc.
- The syringes contain stochiometric amounts of oxygen and reducer, and are connected to a mixing chamber which is in turn connected to a thin hose.
- This hose is connected to ignition elements of one or more detonators, and of course, there must be a nozzle for venting the air which occupied the hose before the gas mixture.

This is a low energy binary system, but does have some complications such as special detonators.

[freaky_frank]

Why not just use a tube like they use in aquariums(sp?), (you know the things where fishes swim in) normally air goes threw them, from a air pump...those tubes are not too thick, and still have a quite big ID, so it isn't to dificult to pour in your explosive...
and if you just pour it in there, with a funnel out of paper or so, you don't pack it.
And it will have a uniform denisty.

[SantasL.Helper]

Those are silicone tubing right? Bit expensive, i've only used hollow shoelaises for the use of a very amaturistic though funny detcord. Just slid a funnel in the cut open lais and loaded it up with X (anything crystalline and not very sensitive). Dunno if that works with HE's though but with primary's it does (dangerous though, to kned a highly sensitive X down a lais)... Anyone knows if filling up a shoelais with HE works for a detcord, as in, being able to detonate it?

[freaky_frank]

Where would you find hollow shoelaises...
You beginner....?

[MightyQuinn®]

I can imagine making detcord with a less viscous HE mixture and filling a tube like my Wagner Power Painter does with paint. It uses a simple diaphragm pump to push paint down a tube.

[andyboy]

Well, this is not recommended but it's how I did it:

http://andyboys.web.surftown.se/detcord.html

I used catheter-tubing which might be hard to find for anyone not working in a hospital, but it ought to be possible to find it in most hardware-stores. The AP was not packed, it was just filled into the tubing using a funnel.

[steve smith]

Can a few people please go over the The Dautriche method again... I am drawing a blank as to some of the details.

I am worried about the filler used. It seems to me that the only way of making improvised det cord would be in set lengths. Otherwise, trying to cut the cord, so to speak, could become quite hazardous.


So far, i like my idea the best. (not because it is my idea) Dropping cotton string into an HE bath, then taking the string and pulling it through a long length of tubing. I *really* like the catherter idea. Small, flexible. Maybe even cheap..?? or even that aquarium tubing.

What would be the best comp for such a device. Best, i would like to be able to cut it, but i dunno if i trust that idea. Unless it is actual PETN.

I do like the idea of maybe taking that catherter tubing and filling it with a syring.


Steve

+++++++++++++

See the above highlighted name? Do this again and you'll be banned. "Signing" a post with your username is redundant stupidity. :rolleyes:

NBK

[A-BOMB]

I personly make a puddy about the consisenty of modeling clay and I roll it out with a rolling pin into about a .5" thick layer by however big. I then use a piano wire frame to cut it into a bunch of .5"x.5" square lengths of explosive, I then take them and lay them end to end and I kneed the ends together to make longer lengths, and I coat it with a mix of plastics and resins. While the mix is still wet I take a roll of cotton gause and I lay it over it and roll it into the mix and then another layer of cotton. Then some paint, I like it in the end because the end produce is somewhat square.

[grendel23]

The whole idea behind the Dautriche method is to compare the VOD of an unknown substance with the known VOD of det cord.
If you make your own det cord, how will you know what it's VOD is?
Making good improvised det cord is an admirable goal, but if you can measure the VOD of the cord, you can measure the VOD of your material directly.
There is a thread on this topic, http://www.roguesci.org/theforum/showthread.php?t=3522. Electronic timing is definitely the way to go.
There is discussion in that thread as to whether a wire embedded in the charge would be a suitable trigger for a timer, but as it shows on page 312 of the 3rd volume of Fedoroff, the Mettegang chronograph uses this method of triggering and therefore it should be useable.
High school level electronics skill is all that would be needed to implement a simple timer that would be capable of accurate VOD measurements.
If you want to know more about the Dautriche method, download "The Chemistry of Powder and Explosives", or Fedoroff vol 3 (harder to find).

[vulture]

Dropping cotton string into an HE bath, then taking the string and pulling it through a long length of tubing.

This is going to seriously affect VoD because of the change in OB and the rather shitty contact between explosive grains.

[Jetex Kid]

Steve, like most salesmen, I’m a little weak on the technical details. But I’ll say this: if you Google on “data acquisition,” you’ll get about 2.1 million hits. :) Add the term “i/o” and the hits go down to 100,000. :rolleyes:

I’m sure that any old oscilloscope could be an accurate timer, too.

Unless you are using ebw detonators, do not initiate using a machine. Initiate independently and then time the interval between broken wires.

[Boomer]

I built a timer to measure VoD, with two thin wires going through the charge at a known distance. The charge is supposed to break the wires, and the processor counts the time between the breaks and displays it on an LCD. I tested the device with a much slower frequency, cutting both wires manually, and it worked.

I got a nasty surprise: With a column of less than 3” length, you always get a counter reading of 1, meaning 20000+ m/s, for all explosives including BP! The reason probably is that the hot gasses stay behind the detonation wave, as they move much slower. They are conductive, thus shorting wire No1 until wire No2 is reached by the shock wave too.

I re-programmed the chip to make it count how long after the first wire the second is shorted (not cut), using two insulated (coil) wires in each probe that are shorted by the hot gases. This new method will be tested soon, I’ll keep you informed.

[SantasL.Helper]

You can find hollow shoe laises at a shoe repair shop. Get those big flat skate shoe laises, if you press the sides you will notice they're hollow.

Filling em up with secundairy X is not a problem, you'd better wrap it up with tape to be sure it doesn't leak...

[vurr]

maybe it is possible to use wave propagation in water(known speed):shock absorbing wall with two holes,explosive stuff (in tube ?) at one side,plenty of free water at other side.
after explosion shockwaves goes also through holes in wall and should give interference picture on other side which can be captured by camera...
then comes hard part:math

[andyboy]

I think you might find this usefull. Dan Williams has excellent plans on a burnrate-tester that is cheap and easy to build. You would just have to modify it for your needs.

http://www.wecreate4u.net/dwilliams/bptester/bptester.html

[Ropik]

I think that relatively good quality detonation cord can be made using (m)ethyl nitrate plasticized with nitrostarch. Very powerful, pliable, can be poured in tubing before thickening and let to reach the putty-like consistency. You must use some type of tubing that does not interfere with methylnitrate filler. I have some, but I don't know for what it is used. It is clear plastic, a bit soft and rubbery, but not so much as rubber :). It is clarified as solvent-resistant tubing.
This is only idea, though. I do NOT know if it works.

[matjaz]

vurr,
a non-explosive reference material such as water will not have a constant shockwave speed. It will depend on the degreee of wavefront compression due to specimen detonation and slowly decrease with distance until leveling off to normal-pressure speed.
Although I don't really understand what geometry you have in mind (explain?).

[Boomer]

The results (see 6 posts up) got lost thanks to who-know-who, se once again:

For the first test I used a 25cm column of ammonia dynamite (40% NG, 50% AN, 10% wheat flour) in a metal pipe of 8mm inner diameter (1mm walls). The probe wires were placed 20cm apart, with 5 cm more main charge plus a small MHN booster on top, to reach maximum VoD ASAP.

After detonation the display read "45" , at 20MHz and 4 cycles per count this equals 36 microseconds for a PIC micro controller. This is 0.2m/0.000036s or 5550 m/s! I had expected approx. 4800 m/s for the small diameter, but the good confinement (metal pipe) may have increased it slightly.

Mechanical accuracy (wire placement) was within +/- 1mm = 0.5%, while counter error was +/- 1 step = 2%. This means the VoD is correct within +/- 140 m/s! That is already in the range of the dautriche error using commercial detcord. :)

This could be improved linearly with charge length, 1% accuracy would require approx. a 55cm column, or using a PIC with hardware interrupt. Much better results can be had by simply using either a faster processor, or a hardware counter (74HCT...) at 100MHz. This will enable me to ACTUALLY MEASURE VoD to within <1% using only a 20cm cartridge! :)

Without commercial detcord, any improvised PETN-in-drinkingstraw/shrinksleeve/waterhose/whatever dautriche test will be twenty times less accurate - meaning you are ACTUALLY GUESSING VoD!

If anybody wants schematics, processor code etc. just tell me. Or wait for the faster version for 1% accuracy. But please refrain from sending me "product samples" for testing ... :D


So far the old post. I recently prepared 2 more pipes (10mm ID this time), with HDN and HDN/AN. Only have to find the timer in my chaos lab ... :p

[freaky_frank]

Why not just let a tube fill with PLX or so....
That's cheap and easy to make, and easy to fill.

[Cordtex]

boomer:
Few years ago, I've scetched out an schematic using 4013 IC's as flip-flops integrated with a digital chronometer and hardware iterrupts. But, never tried to build it(Don't know why).
P.S. I'm not a pro in electronics, just a hobbiest. And your system sounds far pretty pro. How can I get your schematic? :)

[Pietruszkin]

Own detcord?

what da problem? petn is very good, tetryl also (5 km/s in 3 mm pipe)

Greetz

[Joeychemist]

Own detcord?

what da problem? petn is very good, tetryl also (5 km/s in 3 mm pipe)

Greetz

Pietruszkin did you even bother to read the whole post before posting? If you would have bothered you would know that we all already know PETN and Tetryl are prime candidates for det cord. That's what most det cord is, PETN. (That’s what the U.S. army use’s in they’re det cord, same with most comercial det cord). But the problem is making det cord at home, without the fancy machines to feed the explosives into the cord.

One of many problems is achieving a consistent density over the whole length of the cord. For it to work properly you need a consistent density which is very had to achieve at home by ones-self with no machine.

Another problem is getting the PETN or Tetryl safely into the cord, rope, shoelace, ext.You could pack it in with a piece of dowel or something but it’s not too safe and it takes quite awhile to get a even density that will perform the way its supposed to perform.

This may be too dangerous as well but what if you could rig up a sausage making machine to feed the explosives into several feet of cord? Not the ones that grind the the meat used to make the sausage but the ones that feed the ground meat into the skin. It could be done but… I know I won't be the first one to try it. :D

[cyclonite4]

Anyone ever made blackmatch before? How abotu making a blackmatch like machine, which feeds cotton through a slurry mix. The amount of mix can be regulated by pulling the sting through a small pipe, takign off excess, fillign in holes. Before this cotton dries out, maybe pull the string through some sort fiberous (either man made or natural) slieve. Let dry, then pull the whole shebange through a plastic, HDPE like pipe. All of which are eaasily found. Cheap and easy.

When I make fuses I like to use heatshrink tubing as a covering, I simply choose a size about 1-2mm wider than my fuse (unshrinked), and gently (well duh) heat it just to shrink it over the fuse.

Maybe this could be applied as a detcord coating (its very flexible and waterproof) except it could be quite dangerous because the heat involved.

[freaky_frank]

That's why I sayd use a liquid explosive.
Consistent density, and easy to fill.

[Pietruszkin]

hmm

in shop in my city its very simple to obtain a thin, hose-pipe
why you dont buy this, and plainly get some HE to this pipe?
its so difficult?

...
greetings and sorry for my veery poor tongue :P :P :P (english) :D

[freaky_frank]

Damn this whole topic and the 3rd post up is about what we are discussing here.
IT IS difficult to get HE in a tube.....damn can't you read the topic.
There is already sayd that you need to read the topic.
And then you say it again!!!
Pietruszkin did you even bother to read the whole post before posting? If you would have bothered you would know that we all already know PETN and Tetryl are prime candidates for det cord. That's what most det cord is, PETN. (That’s what the U.S. army use’s in they’re det cord, same with most comercial det cord). But the problem is making det cord at home, without the fancy machines to feed the explosives into the cord.

One of many problems is achieving a consistent density over the whole length of the cord. For it to work properly you need a consistent density which is very had to achieve at home by ones-self with no machine.

[pyroluc]

Hello all, recently I've home-made detcord.
with:
-PETN
-aquarium tubing 3 x 5 in diameter
- An air compressor

Here some pics of my detcord, I have a movie from "detcord2.jpg" but I haven't yet acces to the rogue FTP ...

Please excuse my bad english ... :o

[Mr.ANFO]

Hello all, recently I've home-made detcord.
with:
-PETN
-aquarium tubing 3 x 5 in diameter
- An air compressor

Here some pics of my detcord, I have a movie from "detcord2.jpg" but I haven't yet acces to the rogue FTP ...

Please excuse my bad english ... :o



I have just been thinking about using DPPP (Diphorone Pentaperoxide) dvol 9km/sec since the crystals easily pack together to make a piece of detcord. Please someone here give info on commerical detcord size vs application. Thanx

[Guerilla]

pyroluc, that method looks very promising, at least considering the effortlessness. Have you measured the density of the PETN and if its uniform throughout the cord? Also, did you block the other end of the tube with a fine screen of some sort, or what?

[pyroluc]

I had make a calcul about the density that I got , and it was betwen 1.3 and 1.6 :) It's not very accurate since diameter of tube increase a bit...

I don't think that use a primary for detcord is good , anyway , I'll never do it .

I put a piece of paper towel at an end and grip it. :o

[enhzflep]

I realize that this thread has been dead for a while now, however thought i might share something i've just learned. Although not very long, a friend has been making detcord the same way he makes his rocket/safety fuse. Simply by pouring HMTD onto a piece of creased tissue, before rolling up and dipping in NC laquer.:eek: These 'fuses' are then rolled tightly before completely dry, before being allowed to harden.

I metioned to him the vast number of accidents involving hmtd and nitroaromatics, but he tells me he's made hundreds of these things and that his belief is that due to only being about a 10% solution in acetone, it evaporates very quickly (5mins), preventing time for and adverse reaction.

I asked him what sort of loading he was achieving and he tells me its about
1-2gm/meter (great precision:rolleyes:). Anyway, this finished product is about 2mm thick * 70-80mm long. I have seen pictures of an unopened RedBull can cut in half using just 2 of these said cords. The thing that surprised me most was the noise. Really quite soft. Suitable for back-yard experimentation. Obviously a low core-load, but it _does_ do the job he designed it for.

Now the thing that interest me most about this cord is that with a simple modification, one can make a fuse/detonator in 1!:cool:
By making a fuse as normal and then filling the last 1cm with silver acetylide, he has found these to be perfectly capable of detonating the above cord or more interestingly a 90:10 mix of hmtd and vaseline.

Obviously, one could make an entire fuse from acetylide and then cut into 5-10mm pieces to be taped to the end of the normal safety-fuse. However, don't think i'll be the poor bastard that tries cutting 8cm of acetylide fuse into 8 or 16 smaller pieces.:D

It then occured to me that if one were to make fuse as normal, dip 5-10mm in NC laquer and then roll in acetylide powder, before being allowed to dry and be re-coated to exclude moisture. Well, it seems to me that this might achieve the same purpose with less time and danger.

Any thoughts guys?

[quicksilver]

Even using a fuse-making machine the concept is a frought with idiocycracies and that cord is also air compressed during it's construction but since that machine is tough to come by alternatives are needed....Air compression works. Fill a flexable tube with explosive material such as PETN and apply and air compressor via a funnel apparatus that seals the end to the degree that supports the compression pressure. One could alternate between a funnel to fill and a airblower-plug to compress. That would mean that initially the end is sealed by a knot , etc. The above pic by pyroluc are adaquate to illustrate the basic concept. The pressure should be pretty damn strong to compress the material however the trick is to do so every 4-6 inches or so and fill again, re-compress, fill again, etc.
The other important element is to use some butyl rubber in the PETN so as to make the material cut-able and sealable. Ratio should be UBW 1:20 mixed very well. That way the material will not dribble out the end. The material to find is available as roof-coating (it's white) and IS the real Solution Styrene Butadiene Rubber (S-SBR). It's thin stuff & mixes well. Used in a ratio of 1:10 you have a plastic mass that will form in the heat of one's hand. 1:20 will allow the filling of a tube. Since to publish the name of one exact product here would possibly put the company out of business, below is a list of companies that have that same product in both the US and EU. What you are looking for is called: Styrene Butadiene Rubber and is the key to all sorts of products including Deta-Sheet, mil-spec plastic and Du-Pont's det cord. Seek and yee shall find.

Innovative Polymers, Inc. (Manufacturer) St. Johns, MI (product deleted)
Key Polymer Corporation (Manuf. & Service) Lawrence, MA (product deleted)
Normac Adhesive Products, Inc. (Manufacturer) Canada
Noveon, Inc. (Manuf. & Service) Cleveland, OH
NuSil Technology (Manufacturer) Carpinteria, CA
OCM, Inc. (Manufacturer) Vernon Hills, IL
On-Hand Adhesives, Inc. (Distrib. & Service) Mount Prospect, IL (product deleted)
PAK-LITE INC. (Manuf. & Service) Suwanee, GA
Patch Rubber Company (Manuf. & Service) Roanoke Rapids, NC (product deleted)
Permatex Inc. (Manufacturer) Hartford, CT
PHC Industries, Inc. (Distributor) Fort Wayne, IN
RELTEK, LLC (Manufacturer) Santa Rosa, CA
Rubber Mold Compounds & Plastics (Distributor) Clifton Park, NY (product deleted)
Rubber-Seal Products (Manufacturer) Dayton, OH
Scapa Tapes North America (Manufacturer) Windsor, CT
Silpak, Inc. (Manuf. & Service) Pomona, CA
Slocum Adhesives Corporation (Manufacturer) Lynchburg, VA (product deleted)
Specialty Adhesives, Inc. (Distrib. & Service) Pelham, AL (product deleted)
Specialty Products of Michigan, Inc. (Distributor) Novi, MI

[webuyhouses]

I know this thread has been dead for a year, and I apologize if I am out of line by posting on it.

I have successfully dreamed of making something that looks and acts like det-cord, but when I tested it with a concrete block and a bag of water it didn't even crack the block! here are the details:

My chinese pocket scale quit working, so I don't exactly know the proportions. It was a great deal though:rolleyes: .

I dissolved some AP in MEKP, I thought it was about 1:1 (in my dream)
The mixture was still liquid.

The liquid was absorbed into 3 12-inch long pieces of 4mm cotton rope.

2 of the pieces were coated in 2 coats of ping-pong ball NC lacquer.

One more dry piece of rope was soaked in plain MEKP.

1 inch long pieces of the 3 kinds of finished cord were tested for sensitivity to impact by a hammer on steel, flame from a propane torch, and 93% sulphuric acid.


coated mixture:
hammer:detonation, leaving a small amount of the lacquer on the hammer face.
flame: burned down to black plastic goo.
acid: sizzled for 2 seconds (on the exposed end only), then detonated.


uncoated mixture:
hammer: detonated cleanly.
flame: burned down to ash.
acid: sizzled briefly, then detonated.


uncoated MEKP:
hammer: softer detonation.
flame: burned for 1 second then detonated.
acid: sizzled away to ash.

The plain MEKP rope in all tests left string bits laying around.

Okay, so now I have an idea of what this stuff does. The coated cord needs a shock to detonate. I didnt have anything else prepared for this test in my dream, so I initiated the cord with the rest of the plain MEKP cord, with visco fuse, clothes pinned to the coated cord.

I laid the coated cord across a concrete block with a bag of water on top of that. It all went off fine, but the block didn't break!

I have pictures of the setup, and a video of the test. (from my dream)
http://i184.photobucket.com/albums/x163/webuyhouses/S3010018.jpg
http://i184.photobucket.com/albums/x163/webuyhouses/S3010017.jpg
http://i184.photobucket.com/albums/x163/webuyhouses/S3010016.jpg
http://www.youtube.com/watch?v=NHy-vNYXrs4

So now I have questions:
Did the block survive because the VOD is too low? or would a thicker cord make a difference?

Can anyone suggest a use for this stuff?

I had to try making detcord this way because I can literally buy all the materials at the drug store. It seems like it would make a fairly poor detonator for other things.

[nbk2000]

Trying filling a baggie with gasoline and fire it off. Spectacular explosion, or dud?

There's always uses for things like MDC (Mild Detonating Cord) in construction of weapons, for things like ejecting warhead shrouds, splitting casings, ejecting submunitions, etc.

Also, you could use it as shocktube (http://www.roguesci.org/theforum/showthread.php?p=67983), which is very useful too, as you can set up branch lines, loops, and other type of firing systems that you can't do with electrical systems.

If you had P/ETN, you could add that in and see what that does.

Using a larger rope would give you more boom.

Use 3/4" plywood for a target and see if it breaks.

Also, see this thread:
http://www.roguesci.org/theforum/showthread.php?t=6273

It'd help to know not only the ratios of MEKP and AP, but also how much of the mix is absorbed per inch of rope.

[webuyhouses]

I managed to get a crappy scale to cooperate long enough to measure the charge density of my cord.
6.5 grams per meter, without the lacquer coating of course.

commercial garden variety detcord is 5.3-10.6 g/m of PETN.

I haven't been able to make an educated guess of the VOD of the peroxide mixture. Both peroxides seem to be around 5km/s, versus 7-8km/s for detcord.

I considered AP shock tube, but for the risk of re-crystalized AP setting it off while trying to rig a charge, I would rather spend the extra nickel to use a bunch of this cord.

I would like to make PETN, but I wouldn't know where to get pentaerythritol besides starting with methanol and ethanol and trying to oxidize them and go from there.

[nbk2000]

Is the 6.5 gram weight with, or without, MEKP/AP?

You can use erythritol instead of pentaerythritol. This makes ETN instead of PETN, and erythritol is available OTC as a diabetic sugar for about $8/pound.

[webuyhouses]

Is the 6.5 gram weight with, or without, MEKP/AP?

A 7.25 inch long piece of uncoated, peroxide soaked cord weighed 1.9grams

A 7.25" piece of dry unmolested rope weighed .7grams

Equals 1.2 grams per 7.25 inches /7.25 /2.54(cm per in.) *100cm = 6.51 g/m of net explosive.

Thanks for the info, I'll read up on ETN

[nbk2000]

Here's (http://store.honeyvillegrain.com/browseproducts/Granular-Erythritol-4-LB.html) a source for erythritol that's only $5.50/lb.

I don't see any danger in AP recrystallizing in a shock tube as long as it's hermetically sealed against MEKP leakage. Unless you were referring to using dry AP in a plastic tube.

MEKP itself is a primary explosive and would have to be handled with care, but I think that it could be admixed with an inert solvent, like acetone or methanol, to desensitize it, as well as save on MEKP, yet still be shockable by a 209 primer.

[webuyhouses]

For shock tube, I was imagining a hollow tube with AP, or some other primary deposited on the inside by solvent evaporation. Commercial shock tube uses HMX and aluminum powder adhered to the tube electrostaticly, which is deposited as the tube is extruded.

there is a great article about it here: http://www.shocktubesystems.com/drontey.htm

Back to the erythritol, ETN is solid, which means I would have to find a way to load it into a long tube (same as the problem with PETN), unless there is a non-volatile solvent for it which would allow it to soak into a rope.

I say non-volatile because the liquid nature of the explosive charge seems to me that it would prevent sensitivity to friction. If there are solid crystals formed in the rope, or on the wall of the tube, would there be a danger of bending, coiling, pulling, knot-tying, etc. setting off the charge?

My attraction to the explosive soaked rope is also the simplicity of making it. pour explosive whatever over the rope, coat in some non toxic rubber-y stuff.

I haven't given up using the f'n search engine yet, but What I want is a primary with a high VOD, and a solvent for it that wont evaporate and leave sensitive crystals. I could make picric acid, or ETN, and I have an idea for PETN, but I'm not yet aware of what solvent will do the job.

One last thought about MEKP/ AP mixtures, I had better figure the ratio at a cold temperature, because the AP could form crystals in the mix if you try to use the stuff in winter. honestly I don't know if they would be anymore sensitive since there is still liquid cushioning them. The MEKP freezes at "approximately -5 to -10 degrees Celcius". How does it behave when frozen?

[markgollum]

Well, pure ETN melts at 60-61deg C so it could be poured into a coil of transparent tubing as long as you want, then run through a series of pulleys to mill it down to a very uniform, high VOD, and low critical diameter powder in the tubing(remotely of course!).
I am thinking having a 20ft coil in a large pot with 65-70degC water in it, one end of the tubing connected to a controllable suction source ( like a large syringe) and the other attached to the bottom of a container holding a constant level of molten ETN (to exclude air bubbles).
I would dissolve some diphenylamine in the molten ETN to increase its stability and increase its heat of explosion (.5-1% by weight).
At one time TNT based “detonating fuse” was made in a similar way.

[Charles Owlen Picket]

Standard re-crystallization solvent for ETN is ethanol, however acetone is a very powerful solvent for ETN even at room temp. The use of solvents may be a safer way to go.

Studies (Du Pont: 1930's) reveled that ETN is substantially more sensitive to friction, impact, heat, & exterior initiation than PETN. So much so that (in addition to cost factors at the time) it was viewed in the same context as MHN.

Therefore it may not be the best choice for a det cord that might be handled roughly. It's empirical impact sensitivity appears to be on par with NG. Use caution.

[Microtek]

If you want to use a liquid explosive to soak into the string, why not go with EGDN? It is less volatile than MEKP, has a higher VOD, is less sensitive and freezes at quite low temps. In addition, you could use a nitrated cotton string to absorb the EGDN, which would give you an even less sensitive configuration that was less prone to exhudation.
I experimented with something along these lines, but due to noise considerations I never performed any tests.

[markgollum]

Sure, ETN sensitivity is a bit high, but I thought it worth mentioning especially since things based on the peroxides were proposed (totally nuts in my estimation, I will never make a peroxide for anything other than “parlor tricks” again, and no I have never had an accident with the stuff).
If you want det cord you can handle roughly and not worry about much, then I suggest you substitute NENO (N,N’-Dinitro-N,N’-bis(2-hydroxyethyl)oxamide dinitrate) for the ETN in the procedure from my previous post.
NENO is great stuff Mp 88deg C, only slightly less stable then tetryl, about the same impact sensitivity to impact as tetryl, trauzl test 450cc, not sure of VOD at max density, but it will do 5.2Km/s in a 10mm diameter paper tube at the low density of 0.93g/cc.

Off topic :

All you need is an oxalate ester, ethanolamine and regular mixed acid to make it.

This is what I am working on right now, I have already made the dimethyloxalate and tried to obtain the ethanolamine by distillation of an oven cleaner but didn’t get any.
So I am likely just going through ethylene chlorohydrin from ethylene glycol + HCl(g) at reflux then reacting that with excess alcoholic ammonia to get ethanolamine(s),--> distill.

For those replying to my post, please don’t clutter up this thread talking about the synthesis of NENO.
(I hope I am allowed to ask this)

[webuyhouses]

Studies (Du Pont: 1930's) reveled that ETN is substantially more sensitive to friction, impact, heat, & exterior initiation than PETN. So much so that (in addition to cost factors at the time) it was viewed in the same context as MHN.

Considering that, perhaps ETN would be a good choice for dusting the interior of a hollow tube to make shock tube?

If you want to use a liquid explosive to soak into the string, why not go with EGDN? It is less volatile than MEKP, has a higher VOD, is less sensitive and freezes at quite low temps.

I was under the impression the MEKP is quite stable in storage, or do you mean volatile as in sensitive? Even so, I found it takes a fairly hard mechanical shock to set it off. EGDN requires nitric acid, which is tough to get in my area, plus MEKP never gave me a headache.

(totally nuts in my estimation, I will never make a peroxide for anything other than “parlor tricks” again, and no I have never had an accident with the stuff)

maybe I'm just reckless, but the MEKP/AP mixture was not overly sensitive for my taste. I have one more piece of the finished cord from my test sitting in a dixie cup, and I'll retest it in maybe a few weeks to see if there has been any degradation.

[nbk2000]

Stick with what you know.

As long as the cord stays wet with MEKP, there should be no AP crystallization, thus no major risk in handling.

EGDN, while it may work, would be more complicated to make, plus may not propagate since it's not as shock sensitive as peroxides.

I had the idea that a thicker rope could be used as a flexible hostage bomb collar.

Kevlar or steel-braid jacketed (anti-cut) and wire cored (for continuity-checking), a long length of it could be used as both restraint and escape deterrent for multiple hostages. Much lighter and easier to use (and make) than having to set up a multiple remote-firing system for standard bomb collars. :)

Try making a thicker rope, like 1/2", and wrapping it around a melon...and set it off. That'd make for an interesting video. :D

How did you put the NC coating on? Why didn't the MEKP dissolve it?

[webuyhouses]

How did you put the NC coating on? Why didn't the MEKP dissolve it?

I had a jelly jar full of mucus-consistency dissolved pingpong balls, and simply submerged the wet string, hung it to dry, and repeated. The explosive had no effect on the drying of the lacquer coating. The cord has a pleasant plastic feel to it, and is still about as flexible as a piece of stranded copper wire. It smells weakly like MEKP.

My dream tonight involves a gallon jug of mek and peroxide in the fridge, so there should be some more videos coming soon. I might even pick up a dead raccoon or two on my way to my folk's house and see if their mellons like this stuff:D . I really can't do any testing bigger than the first one at my house, because about 14 different neighbors start looking for the damn kids setting off fireworks! pain in the butt living in town.:mad:

[nbk2000]

I noticed all the neighbors in the video. Not a good idea to set off explosives in your backyard when you don't have a backyard.

[Mauser7]

remote-firing system for standard bomb collars

For bomb collars I would think having them hardwired would be the best way to go, as opposed to using a remote-firing system.

For some time the military has been using jammers to keep IEDs from going off in Iraq while in killing range. I don't think it would be too much of a stretch to think that the piggies could have this technology.

A remote-firing system would work fine if you were not in a stand-off with the pigs. However, if you were in a stand-off, and they knew about the collars you had on the hostage's neck, I could see them jamming the signal and then going in to eliminate you. This would be a good situation to wire the collars to operate on the glass break sensors nbk was talking about before. They couldn't shoot you through the window if it would set off all of the bomb collars now could they.:cool:

A plus side to them using a frequency jammer, is that it also disables all of their radios when they use it.

[KrIsPy]

Just a question, but would MEKP/AN make a decent slurry that could be packed into tubing using on of the mentioned methods?

It would be less sensitive than MEKP/AP but slightly less powerful too. This could be a good alternative to more difficult to make or more sensitive fillers for detcord.

[nbk2000]

MEKP is used as a sensitizer for AN, but in a small ID tube, it wouldn't likely be able to propagate the shock much past the detonator because it's critical diameter is larger than a few millimeters.

[rangegal]

Will ETN/DBSP/acetone work? Or will it be too hard to bend when it drys?

[Charles Owlen Picket]

Depending on the grade of det cord (the weight of PETN in a given measurement), REAL det cord feels like what was called blasting fuse. In some instances it feels unique (light weight cord for explosive transfer only). It is ridged to a great degree and when you tie a knot it stays put as the core bends hard but stays bent. What you want is that the core does not get broken when bent! You don't want it to "crimp up".

[rangegal]

But do you think it will break? And would that make it a little risky to handle?

[Charles Owlen Picket]

There are various factors to consider.What pressure is the core itself compacted with? What surrounds the core of PETN (a core within a tube, etc)? Is the material (PETN) subject to the needed stimulus which would create a "hot spot", friction, impact, what have you?

There are criteria available which modern det cord has to meet in order for it to be sold. Research into both the DOT and original mfg criteria will answer these questions in depth. Search various patents & the manufacturer's web sites for hints and determine what would be needed to meet those criteria. PETN is NOT a primary. PETN is sensitive to impact but less so to friction. PETN is generally mfg to be consistent & uniform in it's crystalline form when used for such a thing.

I believe that modern det cord has a polyethylene inner tubing in which the energetic material is packed. This in turn makes it more resistant to impact ignition. It may also have one of a number of buffers or anti-caking materials which make the bending and knotting of same quite safe. Note that often the illustrated knots are not what you end up with when done for real. The knots are never that tight. That alone indicates that the cord has "layers" within it.

[Rbick]

I was back in the shop today at work when I stumbled on something potentially useful. We work a lot with electronics and often strip wires, since some of the work is rewiring. Often, if a wire breaks or you need to cover up excess metal, you apply what is called "shrink tube". It comes in various diameters in large spools, usually black or clear in color. It is placed over the exposed wire and a heat gun is used, causing it to shrink and grab on to the wire, sealing it off.

Point being, I may try and pack some of this with ETN. There would be no need to apply heat and shrink it, but I think the material could be used as a improvised det cord. Here is the web site of a manufacturer (http://www.wesbellwireandcable.com/TubingWB301.html), although I'm am sure you could buy something similar to it at the hardware store. Trick is finding a method of packing it in the tubing. I'll keep reading...

EDIT: I just realized someone already mentioned using shrink tube. Sorry about that. It wasn't very in depth, and I don't think anyone actually tried it. Hope the link gives people a better idea what I'm talking about.

[Charles Owlen Picket]

Hair dryer + shrink tubing = workable.

The mp of ETN and that which would shrink a shrink tube MAY be close however I'd bet that there are some brands of tubing that shrink a lower temps than others.

The challenge is not making a few feet or so.....that's real do-able. The challenge is to make several meters! This is where the air compressors and the techniques in past discussions have issues.

[Hinckleyforpresident]

How about just casting ETN into lengths of plastic tubing? Has anybody tried that?

The only problem that I can foresee would be sensitivity of the ETN.

[Rbick]

Just read through the pages of this thread, they talk about this, as well as in the ETN thread. I'm not sure how one would go about getting the ETN into the tube, there are several ways (such as casting, which you mentioned), all of which are discussed here as well. The only problem with casting I can think of is having to maintain the heat necessary to keep it in a liquid state for the entire length of the tube to make sure it is evenly dispersed. This would be especially difficult if you're making long lengths.

As far as sensitivity, despite it being 1/3 more sensitive than PETN, I don't think it would be too much of an issue. Just be careful :)

[Bert]

Dealing with air bubbles in narrow tubing while filling it could be a problem. Handling large quantities of molten ETN strikes me as... Undesirable. The behavior of the cooled filled tubing when flexed it is also something to think about, some have mentioned an apparent increase in sensitivity of cast ETN compared to the powder. Repeatedly breaking the solidified column while handling the tubing should let you find out just HOW much more sensitive.

[Hinckleyforpresident]

Handling large quantities of molten ETN strikes me as... Undesirable. The behavior of the cooled filled tubing when flexed it is also something to think about, some have mentioned an apparent increase in sensitivity of cast ETN compared to the powder. Repeatedly breaking the solidified column while handling the tubing should let you find out just HOW much more sensitive.

Sorry, I didn't mean that as a method for long lengths. Perhaps you could bend the hose as it was crystallizing breaking up any biguns before they are a problem. I've hammer tested liquid ETN and it wasn't as sensitive as solid uncast crystals, so perhaps that way you could avoid the "Time to wrap it around the tree! SNAP! Whats that? Oh..... Oh god. BANG!" moment.

[Deceitful_Frank]

http://www.youtube.com/watch?v=fqXWTZdj8xU

Thats how you do it!

It was actually two lengths joined together with a 30mm overlap and the slightly longer side cut and rejoined with the same overlap to see if the cord could initiate itself under these conditions. Hence the need for the baked bean witnesses to prove or otherwise.

The left hand section is slightly thicker and more durable as it contains 10% inerts in the form or tissue paper. Hot ETN saturated ethanol was absorbed into this tissue and allowed to recrystalize and dry before the wrapping in Al foil and the compressing layer of PIB.

The right hand section contained just a straight bead of ETN with no tissue.

both cords have the same charge per metre of ETN but you can easily tell which side was the most brisant.

I reckon I got 7-8 metres from this before detonation and was duly knocked senceless and deafened for several seconds... Need to ditch that home-made fuse and get some visco! :D

[Nighthawkinlight]

Nice cord, but holy jebus man! Get some hearing protection and fuse!
Hopefully in the next several days I'll have made some det cord with a multi strand blackmatch style. I plan on APNC or 'AP putty' as others call it. I've found in a 1/5 ratio of NC/AP it will commonly det due to flame in .05g amounts. Certainly more powerful and flame sensitive than AP alone. Of course it is significantly more sensitive than ETN and the like so I may end up setting it in place to det while it drys to avoid accidents in transport.

[Hinckleyforpresident]

Here is a homemade visco machine: http://youtube.com/watch?v=ZHPT5roWrKc

Perhaps the blackpowder could be replaced with PETN or ETN?

Here is a link to photos and an explanation of how homemade fuse machines work:
http://www.truetex.com/visco.htm

[High Density]

I think that it will be a good cord, Someone got a viscomachine??

The question is: What density can you reach with it?
A low density explosive becomes more sensitive, MHN for sure, you can suffer the VOD for reliability then.
If your visco-cord is made for shock transmission only, Density is not a big issue, I think.

I don’t have experience with visco machines, So I know nothing about densities generated from them.
Maybe you can vary it by more tension or less on the spools.

Maybe you can extrude a highly plastic explosive via a syringe or something directly into the windings.
But: how to build that.

The whole visco idea sounds very interesting, And doable.

[black mamba]

I have little experience with visco fuse. Does the thread serve any purpose besides acting as a container for the powder?

Could one use shoe string or draw string as the container? Many shoe laces are hollow tubes of fabric crimped at both ends. Could you cut the crimped ends off and fill the fabric tube with powder? After this you would re-crimp or tie off the ends. Would you be able to coat the fabric to make it water resistant? Sorry if this is completely wrong. My knowledge of fuse is limited.

[Hinckleyforpresident]

It's not all that difficult to make a few feet of det cord (like using shoe lace or tube). The goal is to make tens of meters, to restate a previous post.

Visco fuse is usually coated in a nitrocellulose lacquer coating with makes it waterproof. A similar coating could be applied to a visco det cord. The thread only serves as a container.

The challenge I can foresee with a visco det cord is getting a uniform high density. Perhaps it could be made while the filler explosive is wet with a volatile solvent. The slush would be pretty dense, and the recrystallization would make it denser. Maybe it could then be coated in a second layer of thread and then waterproofed with shrink tube.

[nbk2000]

If you Google for images of 550 paracord, you see that it's a tube of nylon woven around 7 nylon lines.

If you remove the braided line, you are left with a durable tube of woven nylon, which could be coated with a waterproofer after being filled.

How to fill it though...

[Hinckleyforpresident]

If the filler was slushy or at least free flowing perhaps you could pump it in with a little compressor. The pump would have to be durable and powerful though, otherwise it would just clog up.

[Charles Owlen Picket]

It's not all that difficult to make a few feet of det cord (like using shoe lace or tube). The goal is to make tens of meters, to restate a previous post.

Yes; this has consistently been the holy grail. If we look at 550 para cord (which could be fine starting point) then I would suggest a device I once saw in a cooking school used to apply decorative frosting. The device was aluminum and steel and used a CO2 canister to propel frosting in measured levels of intensity. This device would fill the cord with no problem what-so-ever if one were to work a meter or so at a time, continually with no let-up.

I will find a sample of this on the web and post same for I believe it would propel the ETN/PETN with no friction, etc. In fact if I were to further this idea, think of the energetic AS SUGAR & imagine same injected in a manner similar to decorating a cake. If the device for doing so is professionally designed to pump the "frosting" out powerfully & continually enough, the answer may lie there. The device I saw was adjustable for diameter and speed/strength. It was not cheap however.

[Alexires]

Perhaps another way to go about it would be to cut the nylon length wise.

You remove the inner nylon tube, then rig up some way of cutting down the length of the tube, insetting your energetic mixture of choice, then sealing it shut again by either melting it *wince* or using some kind of epoxy perhaps? From memory, nylon is a thermoform plastic.

Imagine two zips, one to open the tube, there is a small gap, then one that closes the tube. If you used something not particularly flame sensitive (PETN perhaps), then you could seal it like that.

Otherwise, what about some heat shrink tubing? Granulated ETN could be put into that heat shrink tubing, then when it is heated at the end of the making process, it shrinks to a tight fit. Waterproof as you see fit (the tubing might not like solvents like acetone for applying NC)

[Hinckleyforpresident]

Perhaps another way to go about it would be to cut the nylon length wise.

I believe this would work fine, but no better then say using epoxied plastic tubing, sealed fabric, sealed leather, really anything sealed. One could probably get a short length of high quality cord, but making all that much would be difficult.

From what I have seen, folding in the explosive would be difficult to do in practice while keeping density and not spilling. I have tried something similar to this with black powder, and it just makes a mess.

Did I understand the idea correctly?

[Alexires]

I'm not sure if you did Hinckley. It wouldn't be easy, but then again, that visco machine doesn't look that easy either.

I have tried pumping BP much into tubes before and it was damn hard. Forget consistency.

Another idea may be to use cotton as a medium to absorb some kind of liquid explosive. Thread the cotton through the tubing, then drip it in.

Otherwise, perhaps we are going about this the wrong way. Instead of pumping it through, why not suck it in? Sucking is much easier than pumping, and as long as it was the consistency of a smoothie, you shouldn't have much trouble getting it into the tube.

Your vacuum pump (or fridge compressor) is attached to a suitable trap, and the nylon cord is attached to the trap. Your melted explosive is sitting there, and you put the tube into the fairly thin melt. Turn on the pump, and start sucking. If your tube squishes shut under the suction, turn down the vacuum or put a valve in somewhere.

At the moment, I'm thinking of using sprinkler hose. While it isn't very flexible, it think it would do a good job and is about the right thickness. You can always buy the more flexible kind, I suppose.

[Hinckleyforpresident]

Perhaps a nitroglycerin/nitrocellulose slush explosive could be used in the suction.

I'll attempt it with some ETN/NG/NM slush.

[Bert]

Perhaps a nitroglycerin/nitrocellulose slush explosive could be used in the suction.
That mixture produces a "gel" not a "slush". The gel would become too thick for your proposed suction method at around 3% NC in my opinion- On the other hand, up around 8% or more, it could be extruded, perhaps with a bit of solvent added as was cordite. Whether the critical Dia. is low enough for this use is another question.

[nbk2000]

If the NG/NC mix is kept very cold, it won't start to 'set' for quite some time, so it'd be possible to pump a (cold) thin gel into the tube (if it's not too small), and let it warm up to set into a rubbery gel.

[totenkov]

That sounds like a good idea NBK, however I would assume this mix to be quite sensative. In my experience NC doesn't do much to lower NG's sensitivity. I have done an MEKP/super fine AN and that worked pretty well, however I think I only got a partial detonation, maybe an ETN/MEKP mix?

[totenkov]

I just got in after trying to set off some ETN that was pressed into a piece of clear vinyl tubing. It was about 9 grams and the 1.5 gram AP cap didn't set it off!

The cap was taped to the side of the tubing and was detonated electronically. When I hit the button, only the sharp crack of the cap going off was heard. After I went to take a look the tubing containing the ETN, there was hardly any damage made to the tubing. How should I apply the cap to detonate the det-cord so it will actually detonate? Maybe put inside the tubing with a piece of paper wadded up and pressed in between the ETN and the cap?

[nbk2000]

Cap in direct contact with the ETN filling, no paper or vinyl tubing in the way.

[totenkov]

I also forgot to mention another charge I made that failed. 10 grams of ETN in an old pill container with a piece of card board tube down the center were the cap would fit in.

I put in the cap and ran out my wire. All that came was a small pop of the cap going off. All the ETN was scattered everywhere. the cap was 2 GRAMS! Maybe the cap needs to be in direct contact with this explosive to set it off.

Has anyone had similar problems?

[Hinckleyforpresident]

totenkov:
I've had similar problems with ETN. I believe that it comes from the ETN not being totally dry or having a lot of impurities. Recrystallize it and give it a day or two to dry, then retry it.

[Charles Owlen Picket]

I think the suggestion of re-crystallization and drying the ETN is very good however I frankly question the initiation properties of AP..... If it's got to be some energetic peroxide then I believe that HMTD will give the best initiation-performance.

If the "primary" is not a real commercial primary, a whole world of things can enter into the picture. To the best of my knowledge ETN should awaken with little effort from a commercial primary. I believe it's a bit more than that of PETN* - but that's still less than a tenth of a gram (for lead azide)! I have heard of ETN that wants to shoot bad enough that most any primary would do. I have read of .25 gram of Hg fulminate in copper foil twisted about the end of a fuse, shot ETN in tests. 1.

* USBoM tests for sensitivity & initiation of secondaries in 1912 included an enormous number of materials, even the nitrated polyols. 1. See E. Weaver

[Hinckleyforpresident]

ETN is pretty sensitive, I've gotten it to go off with .2 grams of acetone peroxide wrapped in tin foil with a fuse. Proximity to the charge also makes an substantial impact, a distance of a few inches can mean no det.

Good advice Charles, unfortunately I don't believe most of us have access to azides or commercial primaries, alas.

[Charles Owlen Picket]

I know that I am out of touch with the common "scene" of purchase for home labs. When I really want to do something of an in-depth experiment, I contact someone who is either going to the University or can get in. I know that is a privilege and not everyone has that opportunity.
But I do know that if you have access to a "Pick-a_Part" type junk your you can get a fast half pound of Na azide.; just get a 1995-7 Dodge Ram airbag thrust system.

Then you're off to the races with a clathrate of a simple azide that would last a life-time of experimenting. On a more mundane level I suppose that Hexamine is still available via the yellow blister packs of "military heat tabs" sold via the internet and some surplus stores for $3. There are ways for anyone to get what they need.

[totenkov]

I just finished dead pressing super dry ETN (I left it in CaCl2 for 5 days) into a piece of vynl tubing which I am going to detonate with my Dad tomorrow (he was so impressed with the video I took of the 300 grams of ETN at Halloween that he wants to see it for himself, though I am only going to do about nine grams :)). One end is plugged with an inch of hot glue and the other only with paper.

[Charles Owlen Picket]

What did you mean by the use of the term "dead pressing"? TTBoMK ETN does not have published dead press figures. It may not dead press until 30k (or not at all). Why would you do so to make a test of initiation sensitivity without comparison pressure data?

[totenkov]

When I mean dead pressing I mean pressing it into the tubing very hard with a piece of dowel wood. I wanted to be as even as possible so the way I did it was slowly adding ETN, pressing it down, adding and then pressing again.

By doing this I got a good uniform piece of det cord that responded very well to the .5 gram of AP :). I taped the 8 inch piece of det cord to a tree and detonated it by electricity 80 feet away. The explosion was very loud, obviously a complete det. It was about 9 grams of ETN.

Next I will try a nitro-ETN mix and see how it performs, and post the results.

[The_Duke]

Totenkov, "dead pressing" in the simplest terms refers to the act of compressing and explosive to such a high density that detonation will not occur or cannot be sustained.

[Charles Owlen Picket]

When I mean dead pressing I mean pressing it into the tubing very hard with a piece of dowel wood....... Next I will try a nitro-ETN mix and see how it performs, and post the results.

I would make a suggestion that (if you have not done so) you keep written records. They actually turn out to be more important than you may think right now.

Often, crystalline structure alters the sensitivity and initiation level of energetic materials. ETN forms differing crystals depending upon the solvent of the re-crystallization solution. They differ in size, shape, & density.

Initiation/detonation is fascinating! There are studies that describe TATP as not being a primary and in fact, not having the properties of a true detonation at all! The study of energetics is tremendously in depth. One does not need to have a grad-level chemistry background (but in helps, I'm sure). But the more one professionalizes oneself the more the field opens up. In addition professionalism helps maintain safety standards.

I strongly suggest you invest in a book that I think you may not only come to love but memorize: Rock Blasting & Explosive Engineering by Perrson (MAY be available via a scan). This was a book that some have come to memorize like Davis. The reason I offer this is that when I would have done some homework I used to have a record such as : "16 grams ETN, density level 1.43; ethanol single re-crystallization; compression + or - 250lbs via manual means; initiation: fuse cap: HMTD 1.25 grams via plastic cap@1.75 density. Placed in contact to .25" hot rolled steel witness plate. Result in .GIF format attached" Or something quite a bit more detailed and from that I have a shitload of info for later. That way I conserve work and get the most out of the experiments.