asilentbob

In anticipation of the holiday coming up... I thought perhaps the BB regulars could post some easy OTC pyro related ideas for noobs. I might temporarily sticky this thread. Think Halloween. So basically colored flames and simple smoke mix. Each is so easy that they really shouldn't need to be expanded upon... BUT in an effort to draw in more serious members to BB... I'll try to expand a bit. Unfortunately I don't have my chems with me so I'm not going to post any pictures of MY stuff... and I don't want to go buy stuff just so I can post a few pics...

Input welcome. Add pics and vids if you can. Doesn't have to be yours, could be from youtube. More media = good.

EDIT: BTW apparently this thread is the top google result for "halloween pyrotechnics"

Green flames... ie. methyl/ethyl borate OR copper chloride in methyl or ethyl alcohol.
I could go into color theory a bit... but nah... basically what you need to know is that methyl alcohol is the best for colored burning liquid flames, 2nd to that is ethyl alcohol. More carbons than that and the quality of the colors decreases rapidly. You want to have NO sodium or calcium impurities.

Methyl/Ethyl borate method...
Methanol is available at car stores as HEET or similar. Read carefully to be sure that it is NOT isopropanol. Generally there is a hint on the front, ie avoid "iso-" anything.


So yeah, avoid the isoHEET. If your lucky you might be able to get methanol in larger amounts as a racing fuel. Methanol can cause blindness and other nasty things. Don't be careless. Find and know the relevant safety info.

S-L-X denatured alcohol is ethanol denatured with methanol. Like 95% ethanol 5% methanol or something. You can get it at most hardware stores.

This is why you read the back of products. They often tell you exactly what you want to know.

Boric acid is H3BO3. Its a really weak acid. It has some use in pyrotechnics and as a roach killer, its also used some times as a dilute mouth rinse (IIRC?). You can find this at some hardware stores near the pesticides. (Or grocery store near pesticides) Its generally in a bottle like below:

If not there you might be able to find it in a grocery store pharmacy area or a pharmacy convienience store, generally like below: (ie CVS, wallgreens, etc)

Avoid BORAX. It has a LOT of sodium.

Now you triple check to be sure that there is no sodium impurities in any of the products. In a cleaned plastic container (that the methanol/ethanol wont dissolve) put in some of the alcohol and some of the boric acid. The amount of boric acid doesn't seem to be very critical. 1tsp per liter should be fine. Some say you need an acid catalyst like a drop of sulfuric or hydrochloric acid. Its worked fine for me without, remember boric acid IS an acid. Cap it. Shake it up for a while. The product is partially borate alcohol esters. IE trimethyl borate or triethyl borate. Its all in equalibrium so you will have ethanol/methanol/triethyl borate/trimethyl borate/water/and probably misc partial borates. In either case the alcohol borates are slightly volatile which helps get the boron up in the flame. Burn some of it. Play around with containers to see what kinda effect it gives. Sometimes little dishes and such will start out great, then as the dish heats up the edges of the flame will go yellow-ish. You don't want that. Its great out of spray bottles. Don't burn it inside though. The smoke can be somewhat irritating due to whatever the methyl/ethyl borate decomposition products are. Because its alcohol/in alcohol it will burn up pretty fast. I don't know of any way to gel it or otherwise slow it down without damaging the color.

Copper chloride method...
Add copper chloride to methanol (preferably) or ethanol. Again, I don't think the amounts are that critical. It should color the alcohol solution a bit to indicate how much is there. Shake/stir to dissolve. Burn. Again, don't burn inside, it can give some nasty vapours due to a small amount of HCl produced. Works excellent out of a spray bottle. Psyco_1322 and I use this in some of our lampare shells. (Aerial shell with liquid fuel and a flash charge to scatter and ignite the fuel. IE fireball in the sky. Or in this case green fireball in the sky.)

Other colors... ie other salts in methanol or ethanol...
Methanol is again the best. Again you want to avoid sodium or calcium impurities unless you want a yellow-orange flame. If you actually want yellow I would say don't waste your methanol for it. Id say get a cheap liquid fuel that will dissolve table salt and use that. Reds tend to be lithium salts or strontium salts. These are both much less OTC. For strontium salts look towards ceramic chemical suppliers. However, be warned there is a high chance there will be some calcium contamination. It might not be enough to matter. Since strontium carbonate isn't particularly soluble you will probably have to make it into a chloride or nitrate salt. Chloride is best. Just react it with some hydrochloric acid. You may be able to find lithium carbonate at ceramic suppliers too. Again you would need to react it with hydrochloric acid to get the more soluble chloride. You might be able to get lithium carbonate at swimming pool supply stores, i can't remember. Blues are tricky. Pure methanol burns with a very ghostly blue flame thats really only easy to see at night. Cesium chloride in methanol is supposed to be a good blue. But thats not really OTC. Calcium chloride will give a somewhat reddish somewhat orangish flame. I don't know where you would get it free of sodium contamination. Its not that interesting IMO.

asilentbob

Smoke...
You basically want a relatively low temperature. You want to avoid an open flame as it will tend to just burn up the fuel completely. Choked work best. Get a good paper tube. Ram some kitty litter down in the bottom for one end plug. If your smoke mix is potassium nitrate based you can probably ram it ontop of the clay plug in increments, if its chlorate or perchlorate based this is far too dangerous. Melting and casting potassium nitrate/sugar smoke mix in the tube is probably your best bet for regular smoke bombs. Then ram more clay ontop of it. Then carefully drill a hole through one end plug using a drill bit between your fingers. NOT a powerdrill. Drill VERY slightly into the smoke composition so that it can be ignited. For rockets the hole is usually 1/3 of the ID of the tube. Since you are not wanting thrust a wider hole like 1/2 or 2/3 of the ID might be better. Actually... You really don't even need a clay nozzle on the end that is going to get lit. You just need something so that there is a bit of space between the smoke composition and the atmosphere so that the smoke comp gets less oxygen to burn with. You might be able to use some layers of aluminum foil and just punch a bunch of small holes in it and duct tape it onto the end that will be lit running your visco fuse through one of the holes... Another possibility is to just make the smoke mix up in a tin can, melting it carefully (NO OPEN FLAMES) to integrate it. Then running a fuse to the composition and placing a metal lid with lots of holes poked in it on the top. The most impressive authentic home made potassium nitrate smokebomb I have ever seen was one that was melted to integrate in a paint can. It was slowed down a lot with bicarb and wax and had many holes in the can so that dangerous pressure would not build up.

Some smoke compositions, many ancient:
http://www.wfvisser.dds.nl/compoDB.html#chapter5

White smoke... ie potassium nitrate / sugar / (sulfur) / (misc other shit)
Experiment with basic KNO3/sugar around 60:40... Adding powdered wax can help the smoke output, but you must slow the base mix with something like sodium bicarbonate and the container for the mix must be set up so that once ignited the composition will get most of its oxygen from the KNO3 and NOT the atmosphere.

Black smoke... ie above + tar, naphthalene, or some other suitable mostly carbon source
Yeah. A basic smoke mix plus something that will burn with a lot of black smoke. Rubber powder for instance. Perhaps various plastic powders.

Colored smoke... ie expensive
Colored smoke is usually accomplished through a potassium chlorate / lactose composition with an added expensive powder dye. The mix burns at a low temperature and is protected from atmospheric oxygen so that the dye is vaporized and propelled out without burning up.

nosfera2

Striker Smoke Device

Here is a device I made many years ago, old BB. I was inspired by German fireworks that have strike fuses much like the device described in the following text. Pictures of finished device are at the bottom.

Step One

Required Materials & Equipment:

1 cardboard tube
1 end plug
glue

Procedure:

First, a container is made for the smoke device. A thick walled cardboard tube is fitted with one end plug using a strong glue. Once this is finished, it is set aside for later.

Step Two

Required Materials & Equipment:

robust heat resistant gloves
eye protection
apron
1 appropriately sized beaker(at least 500mL recommended)
hotplate
distilled water
several books of paper matches
hot water bath
sieve
fire extinguisher

Procedure:

Next, several books worth of matches are carefully stripped of their heads(containing a sensitive pyrotechnic mixture, in most cases potassium chlorate, sulfur, antimony trisulfide, ground glass, and an animal based glue/binder.)

The match heads are then added to a half full beaker of gently boiling distilled water, which is heated using a water bath. This is done primarily to separate the paper from the pyrotechnic composition. After a few minutes, it separates. Any soluble compounds are dissolved and insolubles form a sort of suspension. At this point the paper pulp is sieved out.

Finally, the remaining mixture/suspension is gently boiled until it is a paste like consistency. NOT TO DRYNESS. Once it reaches that consistency, the heat source is ceased. The paste is collected out of the beaker, put on a watch glass, and set aside from the work area.

Take care to clean up the work area for the next step.

Step Three

Required Materials & Equipment:

robust heat resistant gloves
eye protection
apron
1 appropriately sized beaker(at least 500mL recommended)
hotplate
stirring utensil
potassium nitrate
sugar
fire extinguisher

Procedure:

In the second to last step, the smoke mix is prepared. Enough must be prepared to fill most of the cardboard tube. The potassium nitrate and sugar are VERY GENTLY and evenly heated in the beaker accompanied by constant stirring with a strong and rigid stirring utensil.

This is done until the sugar caramelizes and forms a peanut butter like mixture with the potassium nitrate. Once this is achieved, the mixture is promptly taken off the heat source and quickly poured into the single end plugged cardboard tube that has been prepared beforehand. The smoke mix will quickly harden inside the tube.

Step Four

Procedure:

Last, the paste that has been previously set aside is smeared on top of the exposed smoke mix, effectively plugging it. Enough paste is applied to make about a half inch striker fuse. The striker fuse is then let to dry.

Deployment: The technique used to deploy this device is a sweeping motion. One arm holds a red phosphorus strike pad away from face while the other is used to connect the striker tip to the face of the strike pad. It is then swept across the pad and simultaneously thrown.

*Disclaimer: A long standing rule in the pyrotechnic community is to NEVER light a firework piece in one's hand, salute or other, and throw it. However, this piece was designed to be thrown. This device MUST NOT BE MODIFIED TO ACCOMMODATE ANYTHING BESIDES SMOKE COMPOSITION. Failure to follow this advice will surely end in loss of life or limb.

That said, no guarantees are made about the smoke device which is described in this tutorial. This tutorial is for instructional purposes only. Carry out and use at your own risk.*

Finished device:

asilentbob

Yeah, PVC insulation... or other chlorine containing plastic...

psyco_1322

In a bit of time I will get some pics and videos of my pumpkin shells up.

I made two, shot one so far, got a video from about 1/4 mile to see the while thing. Going to film the other from up close. Need to shoot it soon.

nuclearrabbit

Triisopropyl borate can be made with a few drops of H2SO4, but the color sucks.

Methyl Borate
Copper Chloride in methanol

Striker ignition

nuclearrabbit

...Is it too early to start planning for the 4th? :d

nuclearrabbit

Shit mang, I might be home for this 4th.

nuclearrabbit

It's that time again.

I'll be stuck in Germany this year. I've been itching to make some AP but it's a really bad idea.

psychomanthis

It's never too early to start preparing for something awesome.

__________________
"When choosing between two evils, I always like to try the one I've never tried before."
In memory of TOTSE.com

inb4lock

Gonna be picking up some mortar tubes and supplies for canister shells tomorrow. Found my ball mill and it still functions, but I need to get some brass round stock to cut up into media, since I've decided that I don't trust my high alumina ceramic to mill BP.

I also want to make red stars, but I have no strontium salts on hand so I guess I'll have to settle for blue with CuO. Crackling microstars would be nice but no Bi₂O₃... Gah. A star mine with dragon eggs and some coarse Ti, Al, or Fe for sparks was always one of my favourite effects. So quick and easy to construct once you got the DEs and prime figured out. None this year though, FML.

Oh, and I think a 3" Ti aerial salute is definitely in order. Regular ol' 70/30 Perc/IBH with 5% Ti should do the trick, and maybe throw some antimony (III) sulfide in there to sharpen the report. Hm...

This Halloween's gonna be a good one, I can feel it...