11 replies to this topic

[booom1]

Hi all,

I was wondering what the consensus is on connecting electrical ignitors to pyro prior to transporting to site?

Is it generally considered to be a big no-no? Or, okay for some things like candles and cakes but not shells?

We buy 1kg and 3kg gerbs which come pre-wired, and I have read elsewhere on the forum about a manufacturer in China shipping shells pre-e-matched. So I'm slightly confused!

We've experimented in the past with rubbing an e-match-head vigourously inside a length of quickmatch and we couldn't set it off - suggesting a reasonable level of stability.

Any thoughts much appreciated.

Keith
Booom!

[Arthur Brown]

OK not a consensus but my opinion, ....

Igniters are supposed to be friction sensitive (though I've never had one fail on me) so an igniter pushed into QM needs to be secured against movement and rubbing. But securing using cable ties is frowned on because the igniter may be pressure sensitive too!

Being wary of MSER Fusing fireworks is unlimited at the site of use, limited to the factory limits at a licensed factory, or limited to 10kg not at a factory or place of use (including at the store)

So some pre rigging is essential but prefusing is not lawful. in quantity.

Added:

MSER reg 9 -2 d & e

d - allows unlimited fusing on the firing site
e - allows 10Kg to be fused at the store.

Edited by Arthur Brown, 07 October 2007 - 11:56 AM.

[pyrotrev]

Obviously it can and is done a lot: for instance there's a lot of single shot candles, mines etc. that can be bought with igniters pre-fitted, and if you go into SFX, there's even 250g ground maroons (and that's 250g flash lads - ouch ). The thing to bear in mind is that igniters GREATLY increase friction/shock sensitivity above normal compositions, I may be paranoid about this but would recommend the following:
1) The plastic protective caps over the fuseheads NEVER be removed or slipped back on anything that is to be transported: preferably never removed AT ALL.
2) Always add additional protection - e.g. on a cake or candle fold the match c/w igniter back inside the tube, we add additional paper/plastic outer tubes on devices with free match e.g. shells/mines

Edited by pyrotrev, 09 October 2007 - 12:58 PM.

[booom1]

Cheers for the replies, particularly the nod to MSER. Tis always a mission keeping up with the legals, bound by them as we all are!

I'm coming round to the notion of not pre-fusing with ignitors at all - just get everything ready to do on site. We always ask event organisers for overnight safe storage prior to an event - which is when most of our final rigging is done.

Safe.

[Arthur Brown]

http://www.pyrounive...ead.php?t=10695

Is an example of how fusing can go wrong! Yes it's in the States! he was fusing in the garage when his fuse lit and he fired all his show and stock and house!

Made devices with igniters should have minimised the risk of friction ignition during the design and manufacture process.

Lots of devices can go up categories if they don't have a slow fuse I think cat3 can have round 7 seconds (could be 6 - 10 can't remember) If it's only instant then the same device becomes cat4 pro use only. However you can have a visco and an ematch and still be cat3

[paul]

Erm, sounds like he secured BLACKMATCH-leaders to a rack or something with a stapler and accidentally hit a nail or something with the stapler...

I don´t see your point here, correct me if I´m wrong!

Edited by paul, 09 October 2007 - 04:06 PM.

[BrightStar]

Re the e-matches, the usual construction involves a blob of very sensitive primer composition (it has to to fire from a tiny spark) covered with a thin layer of laquer. If this outer layer becomes worn away or abraded by repeated movement, for example if you have a fused leader sliding around in the back of a van, the e-match becomes exceptionally sensitive to friction. Given the next corner in the road, or the moment you pick it up, it may ignite.

Of course, the plastic cover supplied should reduce this problem to some extent. In modern pre-matched stage pyro, the igniter is often covered with a short length of silicone tubing before being placed in the composition. This should be fairly shock proof and there is minimal chance of friction.

Re the example of fusing in the garage, we can be thankful that nobody was hurt. There have been several well reported accidents with staple guns and fuse over the years, some of them fatal. There are specific tools (end cutters, anvil cutters etc.) that are relatively safe to use with fuse, the staple gun is certainly not. A lesson sadly learnt the hard way...

Edited by BrightStar, 09 October 2007 - 09:17 PM.

[MFX]

http://www.pyrounive...ead.php?t=10695

Is an example of how fusing can go wrong! Yes it's in the States! he was fusing in the garage when his fuse lit and he fired all his show and stock and house!

Made devices with igniters should have minimised the risk of friction ignition during the design and manufacture process.

Lots of devices can go up categories if they don't have a slow fuse I think cat3 can have round 7 seconds (could be 6 - 10 can't remember) If it's only instant then the same device becomes cat4 pro use only. However you can have a visco and an ematch and still be cat3

Jeez, he actually says he is covered by insurance!!! He must have a very relaxed insurance company, particularly for the states!

[Arthur Brown]

It was more posted as If you fuse in small quantities or dispersed on firing site then a single accident is likely to be just that, if you fuse in bulk then a single incident is likely to be TOTAL.

Reading that forum we are lucky, They can have state and federal laws to cope with, and some states just ban fireworks completely while some allow you to make your own at home!

[pyrotrev]

The simple safety rule for fusing is to have the minimum possible amount in the work area at any one time. When you've finished fusing an item, return it to your store and get another one out: it may mean a bit of walking , but hey, it's exercise and more fun than going to the gym . Metal dustbins make handy local repositories for match, fuse etc. to further reduce the risk of mass ignition.

Edited by pyrotrev, 10 October 2007 - 12:31 PM.

[booom1]

Had a look at MSER, reg 9-2 e, as pointed out by Arthur, which allows for:

"the preparation, assembly and fusing of fireworks, in quantities of no more than 10 kilograms at a time, at a site in relation to which a person holds a licence or registration for the storage of explosives, for the purposes of a firework display to be put on by that person;"

So I guess it's saying that you can move up to 10kg (net) of pyro from store to workshop and fuse it. Then take it back to store. Then continue with another batch.

In other words, pre-fusing in quantity is lawful (within the quantity limits of the store itself), and obviously provided it's done away from the store.

I think I'm still gonna be more cautious about prefusing with ignitors though!

[Techohead]

hello all,
i make my own electric igniters, and use them for everything i do. when i make rockets i cast my detonator/igniter into the bottom of the rocket, and on ignition it blows itself out. when i make 1/2pound black powder bungers i make them with the igniter in. i've never had problems with the igniters, work 100% of the time and the black powder i use in them is very insensitive to sparking or friction, yet still goes off instantly with power to it.

i've got a video illustrating how to make these easily using houshold stuff: