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Different fusing tecniques for small display items


Pretty green flame

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Evening!

 

Well my precious supply of visco is more or less exhausted and i'm not really into spollette fusing, at least small items.

 

So basicly i was looking through some sites and came across something called "beraq", something maltese IIRC.

 

What they do is that they punch a hole in the insert and prime it with a delay mix. My question is would this work for small items, and how to get accurate timing from this kind of delay. What about moisture problems. Will the slurry not get in the insert and possibly ruin it.

 

Thanks

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Those are made by punching a hole in the beraq, a live salute filled with KClO3 flash normally in Malta.

And then forcing the slurry into the little hole and about 2mm into the salute, that's what give the dalay, the length of pressed comp in the cardboard walls.

There are soms good discussions about beraq'd on rec.pyro.

They use BP binded with arabic gum for the dalay IIRC.

 

Personally I think it would be easier to start with spoilettes, but I don't have experience with both of them.

Good for experimentation tough:)

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I have made them many times, and studied the techniques of making these IN MALTA. If you get into the info pool you will see a lot of them in action and in the making.

 

The way they make it is they fill a tube with chlorate flash(or perchlorate nowadays), and spike it with some kind of thin, strong twine, like linen. Even the ones that are 1/2" OD!!!

 

Then they use a leather hole puncher, like the one they use to punch holes in belts with, and they punch a small hole in the side of the cardboard tube. Small enough to not break through the BP layer that covers the hole when the shell bursts, but big enough to to get the fire inside while flying through the air.

 

I have never heard of inserting anything through the holes, and I doubt anyone do this. Remember the maltese make thousands of these, so the production techniques have to be very efficient.

 

The guys I was with(Lija Fireworks Factory), brushed a slurry of BP with barium carbonate(burnrate modifier) on the side. The % of barium carb varies on the delay they want. However this timing technique isn't perfect, but I like that better. With many of these in a shell, you will hear BRRRRRRRRRRRRAM, instead of one big BAM(all going off at once).

 

Good Luck!

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You could use the sattetini(sp?) delay method where you put flash in and a layer of sawdust, insert a stick of black match and seal. They have a great tutorial on passfire.com
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  • 2 weeks later...
Don't post if you have nothing to add to the conversation. Believe it or not, there are other ways to delay things instead of using fuse. This is a thread devoted to said things. Also, fuse is not as easily available in all parts of the world as it is in the US. Pretty Green Flame happens to be from Slovenia.
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Just go buy fuse, other alternatives are usually real dangerous and should be avoided.

There are a number of ways to fuse things depending on the device. Spollete, the beraq's mentioned earlier.. PGF was asking specifically about inserts. I believe since the original post PGF has rammed some 2 - 3 second spolletes for his shells, I think they'll work out fine.

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Then go ahead and do that, but I was just saying.. If I'm going to make 100g of RDX and use a nice fat HMTD/AP cap, I don't think I'll want to use anything other than fuse, or an e-det system.. Sorry I don't like LE's and stuff like that so I guess alternatives can be used.
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I'dont think you fully understand the nature of this topic. This is not ment to be alternative fuse for HE's this is for divices to be used in small "pure pyro" displays. Such as cake inserts and small aerial salutes or shells. This is by no means for use with HE's.
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I'm usin spolettes sometimes, but The problem is to get the right length when switching comp. for a different tail. You dont want it to burn to fast or too slow, so you'll have to try a few times to get it right.
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I usually make my own fuse. I do have plenty of 1/8th visco but as its about £1 per meter I prefer to make fuse by using Rizla cig papers. Its a little unreliable to use this sort of fuse in an insert but to fuse my rockets I only use this method. I would say I only get about 2 failures per 100 by making my own fuse this way. Even when I do get failures I can always stick another cig paper fuse in the hole and make the item work.

A pack of 50 rizla papers is about 25p ($0.55) from that I can make around 1 meter of fuse. Thats 1/4 the cost of commercial visco. Making it is a little messy and you have to twist them quite tightly to make sure they work. The results are great - if a little short. You can get around that by using king size papers I guess but by using this method I usually have about 10 - 15 seconds to get a safe distance from any display item.

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Have you guys even read this thread? It has nothing to do with random alternative fusings. It is specfically about beraq and if it would work for small items.

 

+++++++++++++++++++++++++++

 

And feel free to start a new thread about fuses, but now get this back on topic, it is interesting.

 

-Rooster

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