Sciencemadness Discussion Board

How do you ignite your BOOM materials?

Zinc - 13-3-2008 at 11:48

So what type of ignition do you use?

I use sparklers mostly for liquid materials and a not common one for solid materials. I make the charge, go to the blasting site, pour some potassium permanganate on the AP in the detonator, insert the detonator in the charge and drop a few drops of antifreeze that contains EG on the permanganate. After around 45 s to one minute the explosive goes BOOM:):) You have to be careful not to add to much or to little of antifreeze to the permanganate because then it could fail to ignite. This method works fine in the cold time of the year. In the warm time it could be dangerous as I have noticed that EG/permanganate ignites much faster. I do not remember how much faster (I tried it last summer). This is a unconventional method but it has never failed me (except one time when I was doing it at night and didn't saw how much antifreeze I added. I added too much and it didn't ignite:().

-jeffB - 13-3-2008 at 12:41

Oh, cool. So you drip on the EG or glycerol or whatever, wait a bit, and nothing happens. How long do you wait before you approach the charge? Are you sure the reaction isn't going to start after a three-minute latency? Sure enough to risk your hand, or your hearing?

I've used KMnO4/glycerol to ignite fires, but I'd never depend on it for a particular minimum or maximum delay.

Zinc - 13-3-2008 at 12:51

I always use antifreeze that contains EG. Glycerin is too unreliable. I waited 20 minutes before I approached the charge the time I added too much (a lot too much) EG. And that is the only time it failed.

Intergalactic_Captain - 13-3-2008 at 13:21

Cannon fuse is cheap - Buy it. Last order I placed at cannonfuse dot com was for 100 feet, he sent me 150 instead. $15 worth, and it'll last me for years.... No CPSC bullshit to deal with either, it's not even considered a "class c" or "1.4g" device by the feds.

Polyol time delays are pointless and expensive...How much do you pay for KMnO4? How many times have you sat there scratching your head wondering why it didn't go off on time? 3 seconds per inch is easy to remember and a hell of a lot more reliable.

Oh...And this really belongs in Energetic Materials, though they'd probably lock the thread or at least change the title to something less kewlish.

Zinc - 13-3-2008 at 13:37

Quote:
Originally posted by Intergalactic_Captain
Polyol time delays are pointless and expensive...How much do you pay for KMnO4?


Around 1.50 dollars for 10g. That lasts for around 12 detonations.
Quote:
Originally posted by Intergalactic_Captain
How many times have you sat there scratching your head wondering why it didn't go off on time?


Never.

vulture - 13-3-2008 at 13:53

Practical discussion of energetic materials on this forum is not allowed.