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Author: Subject: Basting cap manufacture
mabuse_
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[*] posted on 1-10-2010 at 14:16
Basting cap manufacture


Hi,

maybe you can share some of your ideas af homemade blasting caps.

The way I allways done it was a 10mm ID 8mm OD plastic pipe filled with 0,8 to 1,5g HMTD, slightly pressed with a long wooden stick, closed with a wooden endcaps.
The plastic pipe is pretty strong and the cap is mechanically sound.

What worries me is:

-Filling the cap. You can fix it in a vice or something, wear goggles (don't have a motorbike helmet or something like it) but somehow you allways got your fingers involved.
For putting the end cap with the fuse into the pipe i need my hand.

-ESD.
HMTD and metal is risky. On the other hand, the plastic pipe, or straws like many people seem to use are risky too. Especially on dry winter days. A cap has to be conductive.
Maybe some discharge happens just when i put the cap into 400g of ANNM :o
I dont know if aluminium foil wrapped around will do the job properly...


Now I got sodium azide -> lead azide working fine :)
And my PETN from 65% HNO3 is also ready and sensitive enough for <200mg lead azide.


Filling the caps with PETN doesn't speed up my heartbeat. But adding the lead azide does.
I only need a tiny amount, with can hurt me, but propably wont tear my fingers away - but when it's ontop of 1,5g PETN it will be nasty.



What do you think:

1.)
I've got some nice aluminium pipe, unfortunately pretty thick walled (1mm).
No incompatibillities with the explosives, but if something goes wrong it gives larger and sharper fragments with much more range & impact power than the plastic pipe does.
You won't stand beside it anyway when the big main charge goes of, so normally thats not a problem.

But you have to fill the caps first!

Is the very good esd and mechanical protection worth the risk of fragmentation in case of an accident?

2.)
Does any of you have developed some technique of SEPERATING PRIMARY AND BOOSTER?
Something like this:
Another smaller pipe that fits into the pipe, that does not produce fragments, maybe a straw.
Filling the lead azide into the straw and press it. If it goes wrong there are maybe 150mg involved. Straw fragments won't penetrate my goggles. If I don't hold it in my hands it's not too bad.

Then carefully pushing the straw in the main pipe until it touches the PETN. Filling the rest of the pipe with KClO4 Flash and insert end plug / fuse.

->It wont touch the PETN as good as if it was pressed against it. Big decrease in performance?

Pushing the straw down the pipe is still dangerous but I can place it onto of the pipe with a pair of tweezers and push it down with a piece of wood - and keep my fingers at save distance, vision is no longer requiered so I can take cover behind some piece of MDF or something...



How Do you guys handle this?

[Edited on 1-10-2010 by mabuse_]

[Edited on 1-10-2010 by mabuse_]
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pjig
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[*] posted on 1-10-2010 at 15:03


I dont know If I really want to respond to this, but..... DID YOU READ THE PRIOR POSTS WITH HMTD ? !
Think like STATIC!
Im surprised you havent been jumped all over for posting this! Pvc and hmtd are a static accident waiting to happen.., it's not a matter of if , but when..

You have a lot of reading and research left to do.

I cringe at the thought of what you described, It makes me worry that you dont have grasp of the materials you are working with.
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Polverone
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Thread Moved
1-10-2010 at 15:07

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