6 replies to this topic

[megabusa]

This is to all those who have experience at making their own ignitors.

I make mine with 42 swg nichrome wire using the same method as Cooperman - see his web demo.

Now, I coat mine with BP slurry as it works + they are pretty safe. Maybe the drawback with this is that they need quite a high firing current to be instant, about 3 or 4 amps.

What do others use ? If I use a more sensitive coating, will they fire instantly on a lower current ?

What's your experiences ?


Cheers,

Phil.

[whoof]

I did some experiments some time ago.

Prime was too sensitive for my liking.

i wanted something that would ignite APCP reliably.

Eventualy used match composition quite succesfully.

Time- they will go quite quickly with decent current, lead acid or lipo batteries will give ample.

CD can be used for instantaneous ignition but was undesirable for my use, it can go with a loud pop.

  

[phildunford]

I have used the prepared match'chips' which I think I got from the USA. These use a tiny wire and fire on very little current < half an amp.

 

However, they need a very sensitive mix (like coopermans) as the energy from the wire is so small.

[megabusa]

Thanks for replies chaps.

 

I am trying to avoid anything too sensitive for safety.

 

The BP coated ones work, I was just thinking it would be nice to fire instantly instead of up to 1 second.

 

I'm building a firing system & have had to use some quite beefy power transistors so I can use all types of ignitors, including home-made. Problem is, if I use home made (with BP coating) I have to keep the output turned on for at least 1 second, which could be a limitation in speed of sequences.

 

 

Whoof - when you say 'match composition' do you mean as in 'black match' ?

[whoof]

As in swan vestas.

I was using it as prime on coopermans chip ignitors, only thing is i used a small amount of wetting agent to keep it in place until dried.

Delays are common with rocket ignitors but can be solved with current, my little  box will happily poke out 30 amps which if you have a short will happily melt bellwire

[pyrotrev]

I tried a KClO3 or KClO4 & copper (I)thiocyanate mix last year, seems to light readily off standard nichrome wire heads and passed the iron hammer on anvil test :-)

[cooperman435]

A double dipping with NC laquer does make huge changes to safety, Ive made iggs with the tineyest dot of sensative pyrogen, then dipped in NC, then in BP bound with NC to add a flame provider ignited by the senstaive prime.

 

This way the chances of friction ignition are almost gone completely as the sensative is so well protected.