42 replies to this topic

[koobee]

In a lot of comercial shells I see what look like little stars that will softly pop out of the shell and then go zinging all over the place . Forgive me if this topic is covered elsewhere, but my searches turned up nothing. What formulas are used for these stars? As far as I know the comp is pressed in a small tube and has some sort of choke to make it fly.

[chris17]

I opened a commercial rocket with go getter payload and I found that it was filled with short pieces of what looked like fuse. Now I believe this type of flying fuse is called flying fish fuse.

[Frozentech]

In a lot of comercial shells I see what look like little stars that will softly pop out of the shell and then go zinging all over the place . Forgive me if this topic is covered elsewhere, but my searches turned up nothing. What formulas are used for these stars? As far as I know the comp is pressed in a small tube and has some sort of choke to make it fly.

As Chris17 said, Flying Fish fuse will jet around like a go-getter. Bigger go-getters don't need a choke, and are sort of squirted into small tubes. The comp is supposed to be the consistency of pancake batter, and I have read that folks use a squirt bottle like used for mustard or catsup at snack stands to dispense it.

One other note is to make sure your solvents are *dry*, that is, no H2O in them, as the reaction will cause your comp to swell and foam up out of the tubes, or worse. I think I would stick to using flying fish fuse, this particular comp sort of sets off a warning tingle with the copper and ammonium. Maybe I am just paranoid.

Here is a formula from Passfire for Blue Go-getters :
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Blue Go-Getters:
Name: Blue #1
Source: John Driver

Ammonium Perchlorate 50
Parlon 20
Copper(II) Carbonate 15
Aluminum, atom, spher, 325 mesh, 32 micron 10
Saran Resin 5

WARNING:
Make sure acetone and xylene have been dried using damp rid to remove any water from the solution.

NOTES:
Mix 90% acetone with 10% xylene as the wetting solution. Mix with comp until the consistency of pancake batter has been reached, then quickly transfer into a squirt-top applicator container. Fill each go-getter to the top and insert a piece of thermolite or KP black match into the cavity that forms as it starts to dry.

Make only what you can use in one sitting, as it does not maintain the correct viscosity over a period of more than a few hours.
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[Darkstar]

In a lot of comercial shells I see what look like little stars that will softly pop out of the shell and then go zinging all over the place . Forgive me if this topic is covered elsewhere, but my searches turned up nothing. What formulas are used for these stars? As far as I know the comp is pressed in a small tube and has some sort of choke to make it fly.

I'm not sure how the Chinese achieve the go-getter effect - I've never gutted a shell to find out. I doubt it would be flying fish fuse in all but the smallest devices - go-getters are full-blown stars and fly pretty much in a straight line. Blue is (as in most cases) the hardest colour to achieve - completely different formula to the rest. Blue go-getters are also somewhat sluggish. The other colours are Mg, potassium perchlorate and nitrate based. Parlon is present in all formulas, but the Mg versions also include red gum and boric acid. The boric acid is a relic from the formula go-getters were developed from and ought not to be there with Mg, but seems to provide a degree of burn rate control. Omitting the boric acid has been reported as causing the stars to blow apart.

Paul

[koobee]

I have heard of people pressing fast magnesium star comps into tubes for little go getters. The meathod frozentech mentioned is interesting, do the tubes have to be especially thick walled or can I make some tubes with thin walls and squirt the comp in. And saran resin... can I use red gum?

Edited by koobee, 09 January 2006 - 09:11 PM.

[Darkstar]

I have heard of people pressing fast magnesium star comps into tubes for little go getters. The meathod frozentech mentioned is interesting, do the tubes have to be especially thick walled or can I make some tubes with thin walls and squirt the comp in. And saran resin... can I use red gum?

The tubes need to be thin walled, or too much glowing residue returns to earth. 1/2 to 9/16" ID, 1/16 wall and 1 1/2" long spiral wound tubes are usually used, closed at one end with a paper plug.

Saran resin (polyvinylidene chloride) is present as an additional chlorine donor in the blue formula, so red gum can't be substituted.

Paul

[minalth]

It would be advisable to block off one end of the tube in order that the burst charge can only light one end. If both ends were lit, it would not fly so well.

[koobee]

Ok, I will make sure to purchase some when I place my next order with skylighter. Would Barium Carbonate or Strontium Carbonate be a safe substitution for the Copper Carbonate to produce a green or red go getter?

[Frozentech]

Ok, I will make sure to purchase some when I place my next order with skylighter. Would Barium Carbonate or Strontium Carbonate be a safe substitution for the Copper Carbonate to produce a green or red go getter?

Should be a safe sub. Here is another formula ( not tested by myself, from Passfire ) for Red.

Red Go-Getters:
Name: Red #2
Source: John Driver


Ammonium Perchlorate 35
Strontium Nitrate 20
Parlon 13
Saran Resin 12
Aluminum, atom, spher, 325 mesh, 32 micron 10
Strontium Carbonate 7
Iron(III) Oxide, red 3


WARNING:
Make sure acetone and xylene have been dried using damp rid to remove any water from the solution.


NOTES:
Mix 90% acetone with 10% xylene as the wetting solution. Mix with comp until the consistency of pancake batter has been reached, then quickly transfer into a squirt-top applicator container. Fill each go-getter to the top and insert a piece of thermolite or KP black match into the cavity that forms as it starts to dry.

Make only what you can use in one sitting, as it does not maintain the correct viscosity over a period of more than a few hours.

[Darkstar]

Red go-getters using the AP/Al formula will no doubt suffer from the same sluggishness as the blues, but would would look less odd than when mixed with KP/Mg versions. Fred Calev makes some superb, large go-getter shells, featuring every colour of the rainbow (and some in-between). The blues always look to get left behind, however.

Go-getter shells are best given a soft break - the inserts then jet off nicely after a brief pause. If using AP formulas it is important not to use nitrate fuse for priming. PIC would be a good substitute for "Thermolite" (which is pretty similar to PIC, composition wise, but has a woven metal wire sleeve). Perchlorate based ?gold? fish fuse would probably also work.

Paul

[koobee]

Why not nitrate fuse? Would it react with the Ammonium Perch? I have heard of Ammonium reacting with sulfur but would a simple black match be a horrible idea?

[alany]

Nitrate + Ammonia = Ammonium Nitrate which will rapidly become soggy and useless.

KP blackmatch is OK.

[The Swedish Scientist]

WARNING:
Make sure acetone and xylene have been dried using damp rid to remove any water from the solution.

I'm confused.
How do you dry acetone?
If you leave a bottle of acetone open, the acetone will evaporate way before the water does. I'm not sure about the xylene.
(I thought of putting a bottle in a bag, together with a bathroom damp-rid, but won't the acetone or xylene just evaporate and end up on the bag itself, and won't the slowly desolve from the acetone vapours?)

[koobee]

So how about adding some ferotitanium to the mix? Say 4-5%? That could make an interesting effect, that is as long as it won't damage the effect. I can only image that it would speed the mix up.

[fishy1]

I'm confused.
How do you dry acetone?
If you leave a bottle of acetone open, the acetone will evaporate way before the water does. I'm not sure about the xylene.
(I thought of putting a bottle in a bag, together with a bathroom damp-rid, but won't the acetone or xylene just evaporate and end up on the bag itself, and won't the slowly desolve from the acetone vapours?)

mix the acetone with the damp rid, then filter it.