20 replies to this topic

[dave321]

can anyone suggest a deep green bengal comp ?

ive tried using the usual materials (barium nitrate , perc, accroide parlon etc)
but have not really got a deep green, more of a lime green.

i dont have barium chlorate

mabe also suggest a deep red bengal

more interested in colour than brightness

dave

[mabuse00]

I suggest a formula that was posted here recently:

Independence Red

Strontium nitrate 50
MgAl -200 mesh 18
Parlon 16
Red gum 10
Dextrin 5

That gives a very bright but also very clean red (in my opinion), and burns very slowly. You could also try to use PVC instead of parlon to slow it down further.
I would expect it to work as nice with barium nitrate. One might add a few percent to cope with the lower oxygen content.

A similar formula I found very nice was Hardt's Green Star 5:
Barium nitrate 56
Red gum 7
MgAl -200 mesh 17
PVC 15
Dex 5


Both are hard to light with barium nitrate, imho you will need a good two step prime.

not really got a deep green, more of a lime green

Maybe you have a purity problem.

Edited by mabuse00, 13 April 2012 - 09:35 AM.

[Potassiumchlorate]

For green; this one, but at your own risk, since it's chlorate+sulfur:

Barium nitrate 58
Potassium chlorate 21
Sulfur 21

It's about as deep as barium chlorate+shellac.

For red I highly recommend this one from Lancaster:

Strontium nitrate 65
Potassium chlorate 20
Shellac 15

Edited by Potassiumchlorate, 13 April 2012 - 10:49 AM.

[dave321]

thanks all,

i'll try a few of those although i'll stay away from the chlorate sulphur combination,
but it sounds like a good deep colour

i thought parlon would be better than pvc since it has a higher chlorine content

cheers

dave

[dave321]

[quote name='mabuse00' timestamp='1334331199' post='94439']
I suggest a formula that was posted here recently:

Independence Red

Strontium nitrate 50
MgAl -200 mesh 18
Parlon 16
Red gum 10
Dextrin 5


hi again,

now that independence red is nice, i like it very much

i will try and sub with barium nitrate, like the hardt composition, and see what the greens like.

on a seperate colour, i like the phiko blue composition, beautifull

dave

[50AE]

For green; this one, but at your own risk, since it's chlorate+sulfur:

Barium nitrate 58
Potassium chlorate 21
Sulfur 21

I tried this long time ago and IIRC, it was shit pale green as hell

[Potassiumchlorate]

I tried this long time ago and IIRC, it was shit pale green as hell

Pale? How pure was your potassium chlorate?

[ChloRure]

I suggest a formula that was posted here recently:

Independence Red

Strontium nitrate 50
MgAl -200 mesh 18
Parlon 16
Red gum 10
Dextrin 5


hi again,

now that independence red is nice, i like it very much

i will try and sub with barium nitrate, like the hardt composition, and see what the greens like.

on a seperate colour, i like the phiko blue composition, beautifull

dave

I found the comp in another topic and since I dont see any dextrin, I guess that RedGum will act as the binder and I need to use Acetone on those right ?

** Phinko Blue #2 **

Potassium perchlorate 63
Black copper oxide 13
Parlon 14
Red gum 10

[Mumbles]

Acetone or alcohol will work to activate red gum. Alcohol will give you a longer working time with the dampened composition, and is more compatible with nitrile and latex gloves. Acetone will dry faster. If you have a drying chamber, both will be dry pretty quickly.

[Potassiumchlorate]

Red gum needs very little alcohol compared with shellac. I think +1-2% by weight will do. For shellac I use +5%.

[dangerousamateur]

How will redgum alone work as a binder? Is it strong enough?

[Potassiumchlorate]

It's certainly strong enough for a Bengal.

The member Karlos here uses 6% red gum for all his stars, by the way.

[Short5]

Acetone or alcohol will work to activate red gum. Alcohol will give you a longer working time with the dampened composition, and is more compatible with nitrile and latex gloves. Acetone will dry faster. If you have a drying chamber, both will be dry pretty quickly.

Straight alcohol and no water? Why is the dextrin there, just a fuel in this comp?

[Mumbles]

I was responding to ChloRure's question about Phiko blue, which doesn't have dextrin in it as written. There is no reason you couldn't add 4 or 5% in and bind with water though.

[Short5]

I was responding to ChloRure's question about Phiko blue, which doesn't have dextrin in it as written. There is no reason you couldn't add 4 or 5% in and bind with water though.

Okay, sorry to muddle up the thread. To clearify though, in the Independence red formula that calls for both dextrin and red gum, which is the binder? I am guessing one would use alcohol to bind with the red gum rather than adding water to the comp, correct?

Edit: I found a good tutorial by Ned from skylighter that explains what I need.

http://www.skylighte...ubber-stars.asp

Edited by Short5, 24 April 2012 - 01:19 PM.

[Mumbles]

My general rule is that if it has dextrin, it's designed to be water bound. Besides maybe a few specialized things like tube rolling and sparklers, dextrin isn't good for much else than binding.

[Potassiumchlorate]

Mumbles, try barium chlorate and dextrin, 4:1.

It's not as good as with shellac or red gum, but it sure beats anything with barium nitrate or carbonate.

[50AE]

Potassiumchlorate, my KClO₃ was very pure as it is for the other formulas, like for the blues I had. It has always been slowly double recrystallized to huge crystals.

[Potassiumchlorate]

Strange. It might be something with the sulfur or barium nitrate too, of course. It was not quite as green as barium chlorate, but it was very green for being a barium nitrate composition without metal fuels.

[50AE]

Strange. It might be something with the sulfur or barium nitrate too, of course. It was not quite as green as barium chlorate, but it was very green for being a barium nitrate composition without metal fuels.

Now I can agree with this one

Edited by 50AE, 07 May 2012 - 02:57 PM.