35 replies to this topic

[BurlHorse]

Hey guys, sorry for the post and run, anyway, I've been out in the shed tonight working on a pure nitrate green, , and though the one fellow said he did not have any Metals, unfortunatly I had to resort to some Magnisium for a kick to the comp, but I'm satisfied with the result, at least as far as just burning properties and the green is a definite dark Jade, actually pretty not too washed out for a nitrate green, so here goes....

Barium Nitrate----63
Red Gum -----------4
Parlon---------------4----------------------\
Magnesium--------18---180-325 mesh---/ I am going to Play with these ratios...
Barium Carbonate-4
Dextrin------------+4

Yes I realize the +4 Dextrin takes the formula to 100 +4 which I try to avoid as the dextrin does add to the comp chemically, as a fuel, ( Even so, I think this formula is a bit over oxidizer rich) anyway, that's what I came up with after a couple hours work, I will keep tweaking it and try to satisfy the needs of the gent who said he did not have the metals, which is what I was setting out to do, however, without the heat of the Mag, and no chlorate (Barium), I think the stars would have blown alot blind because it just was not hot enough. I went ahead and rolled a pound of stars, (The comp rolled up well to a little over 3/8ths" using # 8 steel shot for cores and 33/66 (Alcohol/Disilled water)), to see how they'll look in the air. Obviously they can't be tested for a few days, I'll keep you posted and I plan to really go after this as I know it's possible, I have seen a deep Nitrate green, so I know it can be done, but the chemistry starts to bore me and my grey matter after a long day so sorry I could not get this one right off the bat.

There is reference to a brilliant green in one of my books, but the formula references a "Phenolic material" that serves two puposes, "The vapor would serve to inhibit any moisture attacking the Magnesium, as well as consuming any free chlorine from the Parlon". There is no specific mention of what this material might be comprised of, Ground bakelight perhaps, I dunno, however it does warrant investigation and I do have a few old phenolic/bakelight switch fixtures, so I'll be back after the above mentioned formula with these switch housings ground up just to see. We, the amatures of this hobbie are the innovators and as such, we owe it to the betterment of the industry to re-examine some of the old texts and re-invent the wheel so to speak with the safer materials available to us..........Stepping off of soapbox now...haha,

Cheers, Stay Green,

Bear

[dfk]

So..what else you got?

[Charged]

I have one question :how to you measure % on a scale.This is a volume measurement and different chemicals weigh different amounts and youll get wrong formula if you measure thing in volume .

[QUOTE]Barium Nitrate----63
Red Gum -----------4
Parlon---------------4----------------------\
Magnesium--------18---180-325 mesh---/ I am going to Play with these ratios...
Barium Carbonate-4
Dextrin------------+4
These measurments are in grams i asume.I want to get things strait.And how powdered these chemicals are?

Edited by Richard H, 27 March 2004 - 07:57 PM.

[Richard H]

Formulae are given in parts by weight and not by volume. e.g a composition weighing 100 grams might contain 20% (20 grams) of X.

[Charged]

Ok thanks!

[adamw]

OK, this has been discussed before (and it really does'nt need discussing again).

In pyro you ALWAYS measure by weight unless explicitly told to do otherwise. It is very rare to measure by volume.

If a composition states:

KNO3 50
MgAl 30
S 10
C 5
Dextrin 5

This means you can, for one small batch, use 50g of KNO3, 30 of MgAl and so on. This will make 100g. If you want to make a 500g batch then you just use 5 times as much of everything - ie KNO3 50 x 5 = 250g etc etc.

Formlae can also be presented by parts, ie:

Ba(No3)2 4
Al 2
Ti 1
Red Gum 1

This may or may not always add up to 10 parts, but it will still work. Again, if you want to make 5 times as much in total, then just use 5x the parts.

Conversely, with both methods, if you want to make only 1/2 as much then only use 1/2 the parts.

If the forumula is in % and the total of the parts adds up to, say, 97% then you know there has been an error. Sometimes forumla add up to more than 100%, ie 104 in Burl's case. This is usually acceptable however as Burl has explained.

[Charged]

What is Red Gum??
It is many formulars i want to know what it exactly is.

[Rhodri]

Red gum is a type of sap from trees. Similar to amber. I'm sure other members will be able to add to this.....

[phildunford]

Good question really...

There's a good couple of pages on it in Lancaster.

Apparantly what is sold as Red Gum can be several different things.

It comes from trees in Australia and extraction involves destruction of the trees - so not very eco-friendly...

The stuff you get is often full of small bits of twig, which seems to support this.

In fireworks it's both a fuel and a binder. It has a quite low MP and although this is unscientific, compositions containing it seem to take fire very easyly.

If you want to know more details I could look up Lancaster for you.

[adamw]

AKA Acacia Gum as far as I know. The world of gums can be very confusing.

[dfk]

That it is.

Gum Acacia is what is also known as Gum Arabic,
Red gum is Accaroides Resin

[adamw]

See... confusing!

Shellac. Shee-lac. Different things also as far as I know...

[Charged]

Yes pretty confusing.Thanks for explanation.It is an interesting thing.

[spawned]

The only chemicals i can reach are emmm potassium sulphate , ammonium sulphate (20% pure not enough for even an endothermic reaction) PLENTY of sulphur and as much NC lacquer as you can take. Not so good ehh i mean kno3 isnt not on the list because it is so common it is not on the list because of my emmm difficulties.

[Rhodri]

Endothermic reaction eh? Please tell me more. Pyro generates heat so I could do with some further explanation on where you are coming from?