underground
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Critical diameter
Can somebody tell me what exactly is the critical diameter and what we can achieve from that ?
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VladimirLem
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google? 
well...explosives tend to not goint to detonate with full speed, when they are blown up in pipes (or other containers) with a small diameter....if the
diameter is too short, some doesnt detonate/stop detonating
but there are hugh differences...PETN can -detonate- without any problems in 5mm pipes/tube but i think the detonation velocity will suffer a bit...
at the same diameter - ANFO wouldn't detonate...at 2-3cm maybe yes but with really low velocity...
you can say, the more sensitive an explosive is, the smaller the diameter can be to get the full potential of it*
at normal charges to blow up a tree its most times not nessesare, but at shaped charges for example, it is/can be...
*the are lists on the internet with the exact CD of different explosives...
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underground
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I was trying to find some informations about that but i couldn't, so that is why i open that topic, Have you got any pdf, or something like that (any
link) so i am going to read ?
I have made some HMTD straw detonators with a diameter of 4.8mm Is that ok or i must made them bigger ?
What do you mean by that ?
[Edited on 24-10-2013 by underground]
[Edited on 24-10-2013 by underground]
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VladimirLem
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Quote: Originally posted by underground  |
I was trying to find some informations about that but i couldn't, so that is why i open that topic, Have you got any pdf, or something like that (any
link) so i am going to read ?
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no....just search at google....
if you read my fist post, you souldt know/guess if this will work 
when you put 200g ANNM (or other easy-to-ignite-stuff) into a plastic bag and then put the detonator cap in it, the critical diameter doesnt really
matter...thats all you have to know...my english skills are too limited/bad for such complex stuff ( )...
...and you dont have to worry about the damn critical diameter at a PEROXIDE-explosive...
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underground
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Alright man 
Thanks a lot
<!-- bfesser_edit_tag -->[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: removed
unnecessary quote(s)]
[Edited on 24.10.13 by bfesser]
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Ral123
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Critical diameter is what will make many charges fail. Contrary to popular believe, it's mostly dependent on the physical form of the material. Hand
pressed crystaline material tends to have smallest diameter. Cast/liquids have many times bigger. Basically, you may want your initiator to have much
higher diameter the the CD of the main material/at reasonable energy density.
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golfpro
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You can watch Ral's video on youtube, cast bit of ETN doesn't detonate in a straw even when subject to 1g of pressed ETN directly above it, only
because the critical diameter is not met. If a standard cap were stuck in the middle of a 20g cast ETN charge with snug fit, the ETN would fully
detonate.
Cast ETN is cap sensitive.
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