64 replies to this topic

[Pretty green flames]

Just had an idea flash through my mind. What would happen if i used Fire gel(the stuff to keep the foundue pot hot ) to coat Blackmatch and to make a slurry out of it and BP. This would help to prevent the KNO3 from dissolving and recrystalyzing. So i did it.

Coated some cotton string with the Fire gel/BP mix and waited for it to dry. Then put a layer of fire gel over the Blackmatch and spread it evenly around using my fingers.

The result is a quite flexible, steady burn, burn through a small hole blackmatch

What do you guys think

[BigG]

Just had an idea flash through my mind. What would happen if i used Fire gel(the stuff to keep the foundue pot hot ) to coat Blackmatch and to make a slurry out of it and BP. This would help to prevent the KNO3 from dissolving and recrystalyzing. So i did it.

Coated some cotton string with the Fire gel/BP mix and waited for it to dry. Then put a layer of fire gel over the Blackmatch and spread it evenly around using my fingers.

The result is a quite flexible, steady burn, burn through a small hole blackmatch

What do you guys think

I think it?s a very bad idea. Firegel should catch fire very quickly in the open ? so I?m not quite sure how you manage to get a steady burn on your string. When you say ?steady? ? what speed are we talking about here?

Also, what is a small hole black match?

[Pretty green flames]

It somehow slows it down to a burn rate of 1.5 cm's per second, my not fire gel coated blackmatch is much more fast than the coated one.

The fire gel film itself is not very flamable when dry. It burns rather slowly.

I can get it on film if anybody is interested.

EDIT: I measured the hole that the blackmatch can burn through and it is 3mm. That's about the same Dia as the blackmatch

Edited by Pretty green flames, 24 January 2005 - 06:04 AM.

[Pretty green flames]

Just a quick question

Is blackmatch good enough to use for cake fusing cuz this is the only thing that can be made in large quantities cheaply.

Edited by Pretty green flames, 24 January 2005 - 04:14 PM.

[adamw]

Not really. It will possibly 'skip' in the cake or could act like quickmatch.

[Matt]

Unless you use your noodle and some hot melt glue.

[kickflip_333]

i didnt use dextrin when i made my blackmatch. just mixed water/alcohol in a 75/25 mix,wetted the bp and made a good slurry. then i just took the cotton string and worked the black powder into the fibers. worked good for me.

[Andrew]

Once when I made black match, I didn't use any dextrin, and Now I hardly every use it. Sometimes I use rich starch. When I made it with just bp with a little extra oxidizer, it was amasing. I made it not by coating one length, but by seperating out the five strands, coating all of them seperately and them twisting them back. A bit of a long winded way I know, but I soon made a few tools to aid production. Anyway, when it burned it had five flames protruding that rotated with the twist of the fuse, the flames were about 10mm long. The thinest stuff I made like this burned through a 1mm hole with ease. When we made a small length of quickmatch it actually blew up and made a pretty big bang, we aptly named it 'bloody quickmatch'

[Mumbles]

The firegel slowed down because the flammable portion is what keeps it gelled, and it is evaporating. The firegel you speak of, commonly distrobuted by Sterno, is a gelled version of denatured alcohol. There are two forms that I know of.

Calcium Chloride is dissolved into denatured alcohol, and it forms a complex with the alcohol. This is the reason you can't dehydrate alcohol with CaCl2. The addition of NaOH or KOH results in the Calcium chloride complex being converted to calcium hydroxide which is insoluble. The alcohol remains attached, and the mixture is gelled from a mixture of the calcium hydroxide complex and excess alcohol. Dyes are often added.

The other, and more used method is mixing solutions of Calcium acetate and denatured alcohol resulting in an imediate gel. I don't know the chemistry behind this one. Another insoluble complex I would imagine. Perhaps something like Calcium Ethylacetate.

[kickflip_333]

i dont like using dextrin kind of unnecessary in my opinion. just one more thing you have to perfect.

[adamw]

Blackmatch without dextrin? Thats like trying to succesfully put up wallpaper without any paste! On a safety note - not using a binder will make the blackmatch very crumbly, giving it potential to 'skip' and also degrade the reliability (if a section of the match were to crumble off). OK if you are using it in pipematch (quickmatch) but not good if it is your main fuse!

Also this is a bit worrying:

just one more thing you have to perfect.

Is this to say that one should not be interested in perfecting things? Is it OK to be half-assed all the time?!

[miniskinny]

Is this to say that one should not be interested in perfecting things? Is it OK to be half-assed all the time?!

Seems like the admins (or at least adamw) should take some sessions on how to teach with patience and understanding, realizing that some people honestly do not want perfection, rather something that works quite well instead of perfectly. There is simply no need to become so extreme in this instance. If it were one of the common misguided chlorate/sulfer posts, i'd understand. People are more apt to take advice when it is given to them in a kinder atmostphere.

[adamw]

Excuse me!?

This is a very valid safety point and it looks like you missed the meaning of it alltogether. I consider the comment made to give the impression of "ah, so what... It'll be OK' - this simply cannot be done in this hobby. You should always try to do things as competently and safely as possible. Especially with fuses - this is of paramount importance!

Its like a skydiver saying "kind of unnecessary - just one more thing you have to perfect" about the most important thing - the parachute.

I said it was worrying, no 'flaming' occured. Also, didn't you see the calm, informative but to-the-point explaination of why this can be a danger?

[LadyKate]

Also, didn't you see the calm, informative but to-the-point explaination of why this can be a danger?

I saw it but only after you pointed it out. I actually locked in on your last line: "Is it OK to be half-assed all the time?! " Which is probably what miniskinny is talking about (not to put words in his mouth!).

In any case, and back to the subject, I've made blackmatch without Dextrin and it does work. I always soak the string in a saturated KNO3 solution first - I just do the whole ball at once. Perigrin mentioned doing that in his book and I've adopted it as a normal way to make blackmatch. Without Dextrin, it is a bit crumbly but it doesn't skip or hang fire. However, blackmatch with Dextrin works better IMHO.

Edited by LadyKate, 10 August 2005 - 12:35 AM.

[Andrew]

I always soak the string in a saturated KNO3 solution first

That's a good idea, I've never thought of that before, might give it a go some time soon.