Sciencemadness Discussion Board

Help with Gerbs, please!

shadowpatterns - 24-8-2012 at 12:02

A novice pyro here. What are some simple recipes for making gerbs? For colorants I have strontium nitrate and and chlorate, as well as barium nitrate and chlorate. I also have sodium nitrate (in addition to powdered Al, BP, spherical titanium, podered steel, Mg of various sizes, Dextrin, and other compunds). Can some of you pros offer me some comps? Thank you in advance!. SP.

hissingnoise - 24-8-2012 at 13:24

I wouldn't use chlorates in gerbs . . .
Comps using chlorate could detonate in mortars by setback!

hissingnoise - 24-8-2012 at 13:26

You could check out the pyro section in"COPAE".

CaliusOptimus - 24-8-2012 at 16:34

Quote: Originally posted by hissingnoise  
Comps using chlorate could detonate in mortars by setback!


Are you referring to chlorate flash? Chlorate stars are quite common and the only hazard I know of relates to chemical incompatibility.


Most star formulas will work for gerbs. Try a standard red star comp w/ 10% granular metal for sparks.

example:
KPerchlorate - 65%
Red Gum -13%
SrCarbonate -12%
Spherical Titanium - 10%

kuro96inlaila - 25-8-2012 at 02:11

There are many type and composition of fountains and gerbs.Avoid deathmix and friction-sensitive compound as making gerb and fountain needs rimming.Once you know how much "this" and "that" were needed in a fountain composition by trial and error you can modify the composition yourself.

Here is some composition of fountains/gerbs:

Fountain #1

Barium nitrate....................................45
Potassium nitrate.................................5
Meal powder.......................................5
Aluminum..........................................45

Fountain #2

Meal powder.......................................72
Potassium nitrate.................................7
Charcoal..........................................7
Dark Aluminum.....................................7
Aluminum (-80/+120)...............................7

Fountain #3

Preparation: Charcoal, sulfur and potassium nitrate are ball milled and very fine. Iron is medium coarse. After mixing (by diaper method), add an equal weight of course meal powder (about 1Fg to 2Fg equivalent), and mix that in too.

Potassium nitrate.................................50
Charcoal..........................................10
Sulfur............................................15
Iron..............................................25

Fountain #4
Source: Shimizu[1], page 127
Comments: This mixture was used in the fountains on the cover of the book. The metal powder can be either aluminum, magnalium or titanium.
Preparation:

Black powder, finely powdered.....................70
Pine charcoal.....................................4
Metal powder......................................26

Fountain #5

Potassium nitrate.................................24
Charcoal..........................................4
Sulfur............................................4
Iron..............................................10

Fountain #6

Potassium nitrate.................................2
Charcoal..........................................41
Sulfur............................................1
Iron..............................................1
Meal Powder.......................................6

Fountain #7

Potassium nitrate.................................2
Charcoal..........................................4
Iron..............................................2
Meal Powder.......................................4

Fountain #8

Potassium nitrate.................................8
Sulfur............................................3
Sb2S3.............................................1
Meal Powder.......................................2

Fountain #9

Sb2S3.............................................8
Aluminum..........................................4
Meal Powder.......................................40

Fountain #10

Sb2S3.............................................9
Dextrin...........................................4
Sodium oxalate....................................6
Meal Powder.......................................40

Fountain #11

Potassium nitrate.................................3
Charcoal..........................................1
Sulfur............................................1
Aluminum..........................................1
Meal powder.......................................2

Blue fountain

Preparation: Granulate the mixture with a small amount of alcohol. Let dry and press into tubes. Very slowly burning mixture. Don't substitute shellac with red gum.

Ammonium perchlorate..............................7
Stearin...........................................2
Copper(II)oxide...................................1
Shellac...........................................0.5

Gerb #1

Meal powder.......................................73
Iron (60 mesh)....................................27

Gerb #2

Preparation: The iron must be treated with linseed or tung oil.

Meal powder.......................................4
Charcoal fines....................................1
Steel fillings....................................2

hyfalcon - 25-8-2012 at 03:27

Go here and read to your hearts content.

http://www.pyrocreations.com/pyro_info___other


Don't ask me why but I just noticed the authors on some of the posts that link goes to. Wouter Visser, sounds very familiar to me for some reason.

[Edited on 25-8-2012 by hyfalcon]