Chinese connection fuse composition

[chrisman]

spitfire Have you tried the modified whistle composition without the sulfur and just increase the charcoal to 4 parts

 

Also can you tell us how do you prepare the composition since in my experience the powder has to be very finely granulated in order to flow easy

 

Can you safely granulate the modified whistle composition ? Have you tried potassium perchlorate and charcoal only composition? and if yes how did it burn

 

Right now I have ammonium perchlorate (I can make some P. perchlorate) but I am using it for rocket propellant and the processing is entirely different

 

Thanks

[spitfire]

crisman,

 

I didn't granulate the modified whistle mix, there was no need to do so. I used straight sieved powder. When the machine is running, it might be necessary to stir the powder a bit to prevent ''funneling'' of the powder. That happens most of the times when you use straight powder. The Chinese used a simple stick or spoon like device that hangs on an arm above the funnel, which is attached to the first powder die and also turns around. Simple and effective! I have tried perc and charcoal, it gave good fuse, but too slow for what i was looking for. For a safety fuse it works. Remember i was looking for aggressive connection fuse for cake items, not safety fuse.

[bob]

what about using a small auger in the funnel?

just a thought

bob

[chrisman]

I did try (something between auger and a drill bit) but the tracer lines were getting tangled with it . Put it a bit higher out of the way and unless you tap the funnel it just makes a hole in the powder

but then again if you tab it you dont need an auger. The best bet is to use finelly granulated powder(finest kitchen sieve and finer) . With finelly granulated powder my machine can work without any help

from my part until all powder is sucked down (my funnel can hold approximatelly 200 gr and that is about 100 meters of fuse).

[bob]

what if you skipped the tracer lines altogether? Edited September 6, 2012 by bob

[spitfire]

bob, your idea might be worth some experimenting. My goal was the Chinese method of making excellent fuse, with nothing fancy, basically anyone can built one at home. We are dealing with just powder that needs to drop down. I always try to avoid more complicated machines when it's about pyro. Of course it is fancy and will absolutely give good fuse, but i like the simple low tech method of the Chinese. They have done it for centuries and have paved the path for us. No need to get too technical. Nonetheless, your input is highly appreciated! It might get more and more people to think of ways of making fuse for themselves.

[chrisman]

It will still work without the tracer lines but as the funnel gets wider with hight you will need to tap on the funnel. The way I have install the t lines on my machine they move from the center of the funnel

towards the funnel wall as they unraver from there spools and they are very effective in delivering the composition. Of course it needed a lot of fine tuning but now the fuse looks better tha the chinese

Whats left to do now is find a composition that burns like the chinese fuse

[spitfire]

crisman, nice job. To get the tracer lines in the right place, you'll just need a metal wire and bend it to ''steer'' the line in the right spot. This is used in sewing machines all over the world. Just by bending it you can tweak it to what you want. I have no doubt you already know this, but i just write it here for other people to make this thread useful.

[bob]

bob, your idea might be worth some experimenting. My goal was the Chinese method of making excellent fuse, with nothing fancy, basically anyone can built one at home. We are dealing with just powder that needs to drop down. I always try to avoid more complicated machines when it's about pyro. Of course it is fancy and will absolutely give good fuse, but i like the simple low tech method of the Chinese. They have done it for centuries and have paved the path for us. No need to get too technical. Nonetheless, your input is highly appreciated! It might get more and more people to think of ways of making fuse for themselves.

yeah that's a good point

would using black match have to much air pockets and turn into qm?

Thanks

[spitfire]

I have been thinking of using black match as a core too, i know some Chinese factories use this method for timefuse. But for my own purposes there is no need to go through all the trouble now. Maybe a year or two later i might experiment with it. Right now i am happy with the fuse i have, and don't have to worry about buying fuse anywhere, anytime. I have never seen any amateur pyro working with this method so it is definitely worth trying! Who knows what the result will be.

[chrisman]

Hi spitfire I already done it. It burns just like a black match but 4 times slower with fewer sparks

I tryed with single, double, and double twisted black match

One thing I noticed with fuse with any composition is that when I coat it with nc through the normal process with a slow motor and a 60 meter travel

for drying (note that the fuse is under tension and it gets 2 coats of nc lacquer ) the fuse when fished is thinner and burns a lot slower

If I just take one meter of fuse and dip it by hand in lacquer and let it sit there the same time as the normal process (with motor under tension)

then the fuse is thicker and burns A LOT FASTER . For example the same fuse with a given composition burns 38 sec /30cm and is 2.2 mm ED

when hand dipped in the lacquer it burns 5 sec/30 cm, 2.7mm ED and thats the same bach of fuse

The burning rate is not always that dramatic between hand and motorised nc coat depending on the composition but is always faster with the hand method

[bob]

Hi spitfire I already done it. It burns just like a black match but 4 times slower with fewer sparks

I tryed with single, double, and double twisted black match

One thing I noticed with fuse with any composition is that when I coat it with nc through the normal process with a slow motor and a 60 meter travel

for drying (note that the fuse is under tension and it gets 2 coats of nc lacquer ) the fuse when fished is thinner and burns a lot slower

If I just take one meter of fuse and dip it by hand in lacquer and let it sit there the same time as the normal process (with motor under tension)

then the fuse is thicker and burns A LOT FASTER . For example the same fuse with a given composition burns 38 sec /30cm and is 2.2 mm ED

when hand dipped in the lacquer it burns 5 sec/30 cm, 2.7mm ED and thats the same bach of fuse

The burning rate is not always that dramatic between hand and motorised nc coat depending on the composition but is always faster with the hand method

so what are your thoughts about it as in is it worth the extra time that it takes to make the black match?

so just keep it under tension when putting on NC and drying it and it will burn slower?

will pingpon ball NC work just as good as normal NC?

sorry about the silly questions

bob

[chrisman]

Bob

IMHO

No its not worth the exrta time

 

Fuse with black match as a core has showed to have the smallest difference in burn rate between the 2 methods of coating

but still slower with the motorised method (under tension) than the hand method

 

The main difference between pp and nc lacquer is the looks and feel of the fuse and it tends to burn a little more aggressively with proper nc

With pp lacquer the fuse feels more rough to the touch and is matt missing that shiny looks like a clear gloss varnish that proper nc lacquer provides

It also doesn't burn as aggressively(the difference is small) but that can be easily adjusted by the composition.

Other than that pp lacquer works just fine and will stiffen and waterproof the fuse

 

You can ask me anything on the subject and if i know the answer I will be happy to reply

 

Thanks

[spitfire]

crisman, this might be a very stupid question.. what is pp...? I have to try camphor too, never used in my NC lacquer.

[chrisman]

PP is ping pong ....lacquer

 

If your NC lacquer is made from ping pong balls or smokeless flakes then you dont need camphor

If you are using nitrated gun cotton and aceton then is a good practice to include camphor(among other additives) as it acts as a stabilizer and also

will make the lacquer more stiff giving more bone to your fuse

I use camphor at 25-50% For example lets say I have 40 grams of gun cotton and I want to aid 40 % camphor that works out 16grams of camphor

I will then dissolved the 40 gr of gun cotton and 16 gr of camphor in a MINIMUM amount of aceton and when fully dissolved I pour it on a glass

table until all aceton evaporates . Then I redissolved the dry nc-camphor in aceton until i have the right viscocity

[bob]

Ok so I have another question

how fast does the powder come out of your funnel

I did a test with a funnel that has a 3/16 inch hole and finely granulated bp, it let out 1 gram in just under .75 of a second, I think this is to fast? I under stand that the faster the machine is running the more it will need but I just want to know how fast it comes out yours just so I have a idea

Thanks so much

[spitfire]

Most times my machine will form a pile of powder under the funnel. (meaning it feeds more than can be pulled through the first hole) The threads going in the first winding take what can be pulled through the first hole, it doesn't clog. It can't jam. It somehow goes by itself. It completely depends on the powder used. It takes a lot of tweaking, some powders need a lot of manual help, some go by themselves the whole process. Especially the fine powders (not granulated) tend to just stop'' flowing'' while the threads move on. I just fix this by manually stir and poke with a stick... low tech but it still gives me all the fuses i want. Color, spark, BP, perc, or whatever.

[bob]

ok thanks spitfire

I"m going to start working on my visco fuse machine soon

so lets see if I got this strait

the bottem wheel (the out side threads) should turn twice as fast as the uper wheel?

what would be a good rpm for the bottem wheel?

12 threads on the top wheel and 8 threads on the bottem wheel should work good?

the bottem wheel is going the opposite way the top one is going?

if I use granulated bp is 24 mesh small anuff? or would it burn to fast for normal use? I would be fine with any thing from 1.5 to 3.5 seconds a inch

what size of thread should I get? (if I do the 12 threads on the top wheel and 8 threads on the bottem wheel)

for ever rotation the bottem wheel makes could the collecting spool take 1.25cm of fuse, or is that way off?

Thanks so much!

Edited October 1, 2012 by bob

[bob]

ok so I think I got a few of the answers I need I just want to double check with you guys

 

is 60 rpm a good speed for the top wheel (I think it will be a had crank so I will be able to chang the speed with great ease)

the collecting spool should take 1.125cm for every rotation the top wheel makes right?

the bottom wheel should turn about 15% faster then the top wheel?

50 to 100 mesh bp is best, so I think I'll try it with what I have and if it works then great if it does not then I"ll just get a finer screen

I think I'll make 2.5mm fuse so the last die has to be 2.5mm right? I'm guessing that the top die would be the bottom die - the thickness of the thread x2 right?

Thanks

Edited October 3, 2012 by bob

[athlon]

Any close-up shots of the nozzles where the powder comes out and the underside of the spool-spinners...?

 

EDIT: nevermind, found a nice pdf where I can see the concept!

Edited October 4, 2012 by athlon

[bob]

ok so I think about 50 rpm is what I'll go for the top wheel

bob

Edited October 6, 2012 by bob

[bob]

I got the dies and the platters made

here are some pictures, as you can see I have a longer piece of dowoling going throught the platters and then the dies attached with a hose clamp to the longer dowols I think they should hold and if they do I should be able to change the dies out really fast

bob

Edited October 11, 2012 by bob

[bob]

I got the threads and bearings yesterday

might make the pullys today

bob

Edited October 12, 2012 by bob

[bob]

I would like to ask any own that has made a visco fuse machine what size there collecting spool is? I'm have trouble thinking of a way to get my collecting drum turning that slow

bob

[spitfire]

bob, mine is 110mm OD.