11 replies to this topic

[Skitzo]

Hello,

My name is Jamie Kelley (creator of the radicalbed dancer "SCHIZOPHRENIA")

WWW.RADICALBED.COM





I use several different pyro effects in conjunction with my performance to build crowd anticipation~

Among the effects are LeMaitre gerbs~

I had been buying them from Star Light & Magic, but decided to make my own due to rising hazmat fees~

In the end, this company was asking more than $100 in hazmat fees to order any quantity of gerbs (plus shipping etc.)

Frankly, it became freakin' absurd! :evil:

So, I decided to start making my own...

I bought some pyro books, various chemicals, tooling, electronic scales, etc.~

However, the closest formula I have found to this effect is "Blue Steel Gerbs" (12% Titanium)

Titanium is definately one of the key ingredients...

Here is the formula by weight:
Ammonium Perchlorate = 65
Hexamine = 10
Steric Acid = 7
Copper carbonate = 6
Titanium = 12

The tubes are 3/4 id. and I use a clay nozzle to propel the sparks several feet~

I do not ram the composition hard in the tube because that causes ignition trouble~

There is medium smoke, but no fallout~

By contrast, the LeMaitre gerbs use smaller tubes with a smaller nozzle and the composition is extremely packed~

These do not smoke at all (preferable) and also have no fallout~

Does anyone know the formula for the LeMaitre Gerb composition?

...Or something close to what is pictured in this message and on my website?

Another good example is in my latest video called "Hypermania" and downloaded on my website~

Thanks for your time,

Skitzo~

[Arthur Brown]

Those who know the proprietry formula will NOT tell! Its a company secret of the manufacturers.

As you quote in dollars I guess you are in the US. Approach Le Maitre in the UK or the US and ask for a list of suppliers for the product you need. Find one close to you, work out the cost of getting legal storage for a number of devices so that your hazmat and shipping charges are more reasonable for the quantity.

Making a reliable replica device may not be as easy as getting a copy of the formulation. Particle sizes and pressing are important too. Also a replica product is likely not covered by your insurance.

[GalFisk]

If it doesn't smoke much, it may be nitrocellulose-based.
If you're going to manufacture them yourself, it's probably better to use one of the public formulas, which are tried and true among hobbyists. If they don't look/work the same, adapt your show accordingly, for instance if the formula is smoky, use the smoke for dramatic effect.
Of course there are insurance (as mentioned), liability and possibly reliability issues with stuff that you make yourself.

[Bonny]

If it doesn't smoke much, it may be nitrocellulose-based.
If you're going to manufacture them yourself, it's probably better to use one of the public formulas, which are tried and true among hobbyists. If they don't look/work the same, adapt your show accordingly, for instance if the formula is smoky, use the smoke for dramatic effect.
Of course there are insurance (as mentioned), liability and possibly reliability issues with stuff that you make yourself.

Gotta hate that reliability part with the homemade stuff...

[Arthur Brown]

Most or the "performance" of a device is in the fine detail. I've seen things being made and the grain size and size distribution is important the mixing is important, and the pressing is important, -even the powder increment between pressings is important.

In home built things like this are less well appreciated. So the devices are usually less accurate or less reliable or less consistent.

[BrightStar]

Skitzo: The Blue Steel formula is probably one of the most difficult of all fountains to make work well. It's expensive, tricky to ignite and often just explodes for no particular reason.

Do you need it to be blue? If not and you just need the silver sparks, try 70% black powder with 20% fine charcoal powder and 10% titanium pressed in a 1/2" x 5" case with a 4mm nozzle. This will still be smoky but is fine for outside use and much cheaper and easier to work with than Blue Steel.

Edited by BrightStar, 07 February 2008 - 10:50 PM.

[Skitzo]

Skitzo: The Blue Steel formula is probably one of the most difficult of all fountains to make work well. It's expensive, tricky to ignite and often just explodes for no particular reason.

Do you need it to be blue? If not and you just need the silver sparks, try 70% black powder with 20% fine charcoal powder and 10% titanium pressed in a 1/2" x 5" case with a 4mm nozzle. This will still be smoky but is fine for outside use and much cheaper and easier to work with than Blue Steel.

Thanks man,

No, it is not necessary that it is blue...

That formula just seemed to work best out of the others that I had tried~

Mainly, I am interested in the "crackling titanium effect", shear volume of micro-starbursts and maximum distance of the sparks~

From my experience, there are two major things that will cause it to explode:
1) Nozzle size cannot be smaller than 3/16
2) Titanium content cannot exceed 12% max

The ignition problem was solved by "lightly tapping" the composition instead of ramming it with hard blows~

However, LeMaitre's formula was as hard as a rock!

Do you agree that the LeMaitre effect was possibly nitro-cellulose based as someone else mentioned?

The actual mixture was gray~

I honestly wish I could get rid of the smoke...

Any further thoughts would be appreciated~

Skitzo~

[MDH]

Cast Iron is adiquate enough for "bursting sparks" isn't it? You can also use aluminum with a delay agent, sometimes this will make it appear to "explode". There's a lot of ways to make a crackling effect. What magnitude are you going for?

[FrankRizzo]

If you don't have a BATF mfg license, you're going to run afoul of the law in the US because you're using the devices for business purposes.

[Arthur Brown]

Also unless you have the money or facilities to get your device a UN transport category it can be considered 1.1 and need a hazmat driver and vehicle to move it from the factory

MOST of the cost of stage / proximate pyro devices is the cost of getting and renewing all the certifications.

[FrankRizzo]

Also unless you have the money or facilities to get your device a UN transport category it can be considered 1.1 and need a hazmat driver and vehicle to move it from the factory

MOST of the cost of stage / proximate pyro devices is the cost of getting and renewing all the certifications.

It will at the very least be considered 1.3G which requires a CDL with hazmat cert. in the US. Check with your liability insurer as well about the use of self-mfg devices..I bet good money they won't honor a claim if someone gets hurt.

Do the right thing and keep buying the gerbs from LeMaitre. Their products have consistent effects with a known burn time and spark reach.

[al.]

blue pencil

Edited by al., 10 March 2008 - 11:36 AM.