7 replies to this topic

[GBthriller]

From across the pond again!

Greetings- My name is..My name is..My name is GBthriller. Local display master of 20 acres known as mine. I'd like to tell you more about where home is but that is information only Homeland Security cares about, I wont bore you.

I'd like to say what a privilidge it is to post here. Thanks tons (metric tons if you prefer).

I need to go right to an issue I'm dealing with now:

The wife says make em white, I like white stars. O.K. what could be easier? Hmmm.
3 days later now and my stars wont stay lit in the air fer nothin. Yes they are dry. A 3/8 by 3/8 pumped (sorry no metrics) star burns for about 4 to 5 seconds on the ground. The 3F equivelant size dried powder prills runs about 2 to 3 seconds in a one gram pile. Nice white, but not fast enough.

Here's the formula:

Potassium Nitrate 51
Antimony Trisulfide 17
Sulfur 18
dextrin 3

I think its Davis' formula. I got it somewhere around here. The batch contains all my Antimony Trisulfide, the pressed bunch is only about 20% of the mix, so its not too late to fix this.

Tried already: adding BP meal, C, more nitrate, Barium nitrate, Zinc, Brass, Magnalium, and combinations of those things.

What worked: meal obviously, C helped considerably, Zinc helped, but added a green cast, Mg/Al and C really increased sensitivity and rate, and was perrrdy.

The desire is to save my Kilo of white mix, and get useable stars. OR should I use it in lances (too smoky zi think) or fountains?

Any suggestions? Thanks for the ears. Looking foreward to helping you all some day!!!

[RegimentalPyro]

When you list what worked, how did you add those chems to the comp? Did you mix them in and make new stars out of this modified comp or did you roll a layer of the chem round the stars you already had made?

If the stars burn nice on the ground but not in the air then it sounds like you problem is one of finding the correct prime. I've found that passfire's "hot dragons egg ignitor" prime lights 99% of my problem stars. Formula as follows

Perc 70
Magnalium 20
Redgum 10
solvent=60% water. 40% Alcohol.

You may need to roll a layer of meal round this as a final prime.

[Rip Rap]

3 days later now and my stars wont stay lit in the air fer nothin

Did you test fire these stars from a star gun, or were they tried straight in a shell?

4 - 5 seconds burn time for a 9.5mm star sounds quite long for a static burn test. The composition you used should ignite & burn relatively quickly - unless you used loads of pressure when you pumped them and made a really dense star. Does the star ignite & burn cleanly, or sputter, leave residue etc? Have you primed them, if so, what with?

If the star burns cleanly & quickly on the ground, I agree with Regimental's assessment - go with the prime he suggests.

[GBthriller]

Did you test fire these stars from a star gun, or were they tried straight in a shell?

4 - 5 seconds burn time for a 9.5mm star sounds quite long for a static burn test. The composition you used should ignite & burn relatively quickly - unless you used loads of pressure when you pumped them and made a really dense star. Does the star ignite & burn cleanly, or sputter, leave residue etc? Have you primed them, if so, what with?

If the star burns cleanly & quickly on the ground, I agree with Regimental's assessment - go with the prime he suggests.

Thanks for the help fellas!

Yes the 5 second burn is on the ground. The stars seem to initially light from the star gun, then the seem to blow out! I've never seen this before, I meal primed a few just for testing. The 3 to 5 second burn is for loose piles of the comp, still seems too long. I'm quite sure of the mix ratios. the nitrate was exposed to atmosphere for a long time though, would you expect some kind of degradation? I aslo tried (coffee) grinding a small amount of the comp to insure it is fine and mixed. Still the same result.

I'm lost on this.

[GBthriller]

Let me ask one more question:

To try and solve the problem, the added elements were just measured into 1G of dry comp and test burned. I got quantifiable results with this method. Again the .05 G of C and .05 of Mg/Al added made it burn much better. Do you think this is a good solution?

If not can I crush the stars I have made and remix and rebind them? Dextrin, is it reusable if redivided?

Thanks again!!

[Draco_Americanus]

I would think to use a ball mill when grinding the chemicals, it does a better job then a coffee grinder.
As far as I know it's never a "good" idea to regrind and mix a compleated comp. I have "reset" a bunch of strobes a buddy of mine steped on with good results. I guess it depends on the nature of the binder.

[adamw]

Is that aimed at me homie!?

Of course you are welcome... but only a few at a time!

[GBthriller]

Is that aimed at me homie!?

Of course you are welcome... but only a few at a time!

Yeah, I was in yer face cuz you was bustin on that other Yank newbie.

Now I'm only going to say this once because y'all cant read too good. We Americans are here because this board needed some spectability, and we all know that since you Brits left the United States to start up yer own establishment, thing havent gone so well. Thats O.K. Yer young and yull learn.

Honestly, I'm a red cheeked Welsh decendant, and very honored to be acceped here. Thanks!

As for the white star issue, I've decided to make it a flash trough, adding some special things that go (fast) white in the night. Still for the sake of progress I wish I knew why is was so slow as originally made.