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Paper fuse


THEONE

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I have made paper fuse many times and the best so far is a mixture of kno3/sugar dissolved in water. The problem is that sugar is hygroscopic and if i store it unsealed, it become really wet. I was thinking if there is any fuel that can be burned quite fast, be soluble in water and non hygroscopic in order to replace the sugar.
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BP in a selection of grades is exceptionally useful! Lift, break, fast and slow fuse etc.

Edited by Arthur
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BP in several grades will make fast fuse, slow fuse and delay fuse as well as lift, break and propellant. It also works in normal humidity.

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  • 3 weeks later...

BP in several grades will make fast fuse, slow fuse and delay fuse as well as lift, break and propellant. It also works in normal humidity.

What’s the best method to make a reliable, waterproof, thin and very fast burning fuse?

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What’s the best method to make a reliable, waterproof, thin and very fast burning fuse?

you can make normal black powder black match but using waterproof pipe putting plastic tape on the paper pipe

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What’s the best method to make a reliable, waterproof, thin and very fast burning fuse?

Blackmatch type of practices are probably the closest approach to getting a type of fuse without more technical means. One can use dipping technique to apply a rather even layer of fuse composition on a thread. This can further be coated by a waterproof layer using the same technique. For waterproofing one can use diluted glues, varnishes, clearcoats....even diluted silicone adhesive is an option, but it tends to cure for days under such conditions. Does yield a superbly waterproof and flexible fuse though.

If doing it "manually" the cons are limited lengths and varied repeatability......the latter can cause unreliable ignitions and variance in fuse properties. Both are highly detrimental effects.

A step further would be the construction of a visco machine. It can be a rather involved project, but renders one capable of producing a reliable and high quality product with chosen parameters.

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  • 3 months later...

I'm replying because I can't start a new topic. And because this thread, though a little old, is relevant to my comment I think. Or my comment is relevant to it. Whatever.

 

So, I make a few pyro devices from time time. Saxons, gerbs, glitters, rockets etc. Nothing Earth-shattering, but they amuse me. Anyway, I've been trying to get a decent quickmatch for a while now, and I just haven't been able to. I think it's my fuse mix, maybe it's not soaking in correctly or I'm using too much binder. Not sure, but the resulting QM is just not great. I mean it's OK...if I use 3 or 4 strands per tube it works fine...but that seems wasteful. It's also not very fast, and the blackmatch itself is just not reliable enough when unconfined. So I was trying to come up with alternatives to QM...and I think I have.

 

I present: FIRE TUBES!!!

(they're actually just paper straws coated on the inside with BP, but FIRE TUBES!!! sounds better imho).

 

As hinted at above, what I did was to take some paper straws, I think about 4 or 5mm diameter (slightly wider than one of those bamboo BBQ skewers that you can get) and about 10" long. I don't have one with me as I type this otherwise I would give accurate measurements. I cut these straws up into halves and quarters, but also used some full length.

I took some BP + a few % dextrin, mixed it up with a little water until I had a fairly thin mixture...the consistency of single cream at most. I had an old CPU thermal paste syringe and I used it to squirt (inject?) some BP mix down a tube a few times (you have to do it a few times as the straws are, rather unsurprisingly, a little water-resistant), then turned it 180 degrees and squirted a few times at the other end. I rotated the straw as I squirted. You don't need to coat the entirety of the inside, just a few solid 'streaks' all the way along is good enough. Once that's done, take the bamboo skewer (as mentioned earlier) and dip one end about half an inch into your BP slurry. Make sure it's well coated. Then take it and rub it around the inside of each end, the first half inch or so, to make sure that part is fully coated with your BP slurry. Then take each end and dip it into a little dry meal powder so as to coat the inside of the freshly-painted tube with a half inch of meal on top of the half inch of slurry that was just applied. This is an important step as it makes certain there is a good amount of BP at each end to ensure ignition of whatever is next in the train. Tap through to get some meal to stick to the 'streaks' inside. Now leave to dry. I found 24 hours in a drying box with a little calcium chloride was more than enough.

 

Once dry, the application of flame to one end will resutt in the instant, and I mean instant, passing of fire to the other end. It's seriously quick, as good as any QM I have seen professional or otherwise.

 

But wait, it gets better.

 

I was struggling for a while trying to figure out how to attach the tubes together quickly, easily, securely and crucially around corners and bends. Turns out can just put two together with a bit of masking tape, that will even work to a 90 degree angle or so, but I found a better way.

Take a fire tube and make a little hole in the side with an appropriate sharp and pointed implement, make it a clean hole about 2 mm diameter, then place the end of another tube against it and fasten with a bit of masking tape. Now apply flame to the end of the first tube flame will instantly shoot out the end of that tube and the one that was just attached. And this works for multiple tubes. You can take a full length tube, make a dozen little holes, and attach a dozen tubes to each of those holes. And a dozen more of each of those first dozen. And so on. I've tried it, it works.

 

The flame, though quick, has been enough to light every compound I have tried it with. Which isn't that many to be fair, but it ignites granulated BP reliably and also Barium and Strontium nitrate based mixes. I would imagine the addition of 10% Al to the BP slurry would not affect burn time that much but would greatly increase ignition capability. I haven't tried that yet though.

 

These fire tubes have many advantages - they are very efficient with your powder, quick as a flash, very reliable, easy to make, simple to join together, fairly sturdy and completely spark resistant.

The disadvantages are you can't just make a metre or so in one go like you could with QM, and I haven't yet figured out how to add a delay. Instant ignition is all well and good in certain circumstances, but sometimes you want a little pause...and I'm not come up with a way to build that into a fire tube. I'm open to suggestions though.

 

So that's it. I've not heard of this type of fusing device before, but maybe someone has come up with the idea before me and dismissed it because it's crap in some way I haven't found yet. If not, well then you heard it here first.

 

Cheers

 

 

BrettR.

Edited by BrettR
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Hi Mark,

 

I have a video now (apologies for the quality). And some pics, though annoyingly I wasn't quick enough on the button and missed the larger of the two tests I ran.

 

First pic is of the kit I used:

post-22566-0-44220500-1575325698_thumb.jpg

 

You can see paper straws (ID 5mm, length 20cm) left as whole and also cut into halves and quarters.

There's also a small glass bowl with my watery BP slurry in it, the syringe used to squirt the slurry down the tube, a bamboo skewer for working it into the ends and a small tub of meal powder for dipping the ends in after.

 

Here is the first set of tubes I was going to film:

post-22566-0-45380000-1575325701_thumb.jpg

You can see the myriad connections - corners, right angles, many tubes attached to the length of one etc. I finished assembling it after I took the photo, lit it but then f*cked up the filming. Sorry.

 

Here is the second set:

post-22566-0-01610800-1575325826_thumb.jpg

I took the pic after I had lit it, but you can see clearly the structure. Each tube ignited perfectly. A little visco was inserted in the bottom and lit, the flame shot up the 'trunk' and out through the 'branches', as you can see in a pic a little further down.

 

This is a vid of a single, full length tube. I *think* it's slo-mo, but tbh my S4 is quite old now and I can't say for certain. It should be 100fps, though it doesn't look it.

Whoosh, eh?

 

Now the second test:

Again, doesn't look like slo-mo...though my camera settings insist it is.

 

It's very quick so I was able to pause the salient moment for all to see:

post-22566-0-52842400-1575325704_thumb.jpg

Each tube lit beautifully. And even though I messed up the vid, I can assure you that each tube on the first 'assembly' also lit beautifully.

 

So there you go. It works. It will not replace QM as it's simply not as good for certain situations, but it's a very handy alternative should you need to fuse something up quickly, or need to ensure instant ignition over multiple devices but (for whatever reason) are unable to use QM.

 

I'd be interested in comments, criticisms, advice etc.

 

Cheers

 

 

BrettR.

Edited by BrettR
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  • 3 weeks later...

Ok i actually found a simple way to make a non-hygroscopic, good quality paper fuse super easy. I got inspired by "erythritol better than sorbitol" thread. I simply add some erythritol into the paper fuse mixture. My final composition is 76-80% kno3, 24-20% erythritol, +1% red iron oxide and +100% water. Heat it up and dissolve everything. Soak pieces of paper tower and let them dry. Done

Edited by THEONE
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