boric is a poison, so it needs some care - can produce some noxious fumes, depending on quantity - probably don't want to use it indoors, at least not w/o super ventilation. I definitely wouldn't eat/blow fire using it.
And, as with anything, once you've used it, you've got the residue in your wicks & dipper to think about.
(I don't play with it that much, so others may be able to give better specifics.)

The kero-heater-in-a-pipe idea kinda scares me a little.
you want to make *sure* that whatever temperatures will be reached in there can be withstood by *all* components -esp feeder connections- otherwise you can get blow-back (flame) into your fuel tanks, among other party favorites.

also, wheres your oxy coming from?

a fire cannon requires a propellent (as in something to make the fire move), which means more sensitive high pressure connex, or at least some kind of blower... really you probably wannna study up in some depth on these kinds o systems before you start tinkering..

By saying these things I don't mean to be discouraging at all, its just - if I read about you in the newspaper, I don't want it to be "man blows up neighbor's chihuahua" or something..

remember, kids - safety third.

lovjvol

Boric acid dissolves better in an alcohol-based solution; you won't get much color at all from mixing it with kero or other bright-flame fuels, as they overwhelm the colored flame.

Check out www.skylighter.com/ for your chemical supplies, pyro materials, as well as instructional videos and books. I've done business with them before, and they're really nice and willing to try to help you figure things out if you call and ask questions.

I use green and blue on my peacock tail

The recipe I got for green fuel was really mysterious, which bothered me, but it works, and I've been using it for years.

1 gal denatured alcohol
one package boric acid (pick it up as an eye wash at your local RX)
about 2 cups epsom salts

in a 'specially marked fuel canister, fill with alcohol, add boric acid, add in salts a little at a time, mixture will get slushy. I know this is vauge but it'll make sense when you get to it. Cap securely, and let mixture cure at least over night. The longer it sits the more saturated your color will be.

it does leave a residue on wicks, your next burn will have a green tinge to the flame. The alcohol will evaporate, leaving the salts behind.

you don't want to do any body work or transfers with this mix, the alcohol and boric acid will give you a nice rash, and definitly don't eat with it.

Someone has been trying to connect with me to give me a bunch of colors, but we keep missing each other, when I get the goods, I'll pass on the recipes.

There is a website a while ago that gave the element to add color to poi wicks.. i found it thru a link to home of poi, can't dredge it up at this moment tho.. I have friends in a fire sclupture group called Therm and we played around unsuccessfully with coloring wicks but they for sure have the color thing down for their fire sculpture but they are using different fuels. All that stuff is very toxic to breathe and stinky..would love to find out how to sucessfully color wicks if anyone has any tips.. kali ....