Star Compositions and Mine Effects

[wizard7611]

Ok, so before I start to ask these two questions, I watched this video:

https://www.youtube.com/watch?v=G5R-F1RmL5Y

It directly states in the video when you add metal salts to the black powder, it creates color.

Question 1: If Zambelli Fireworks only adds these chemicals to to the mixture, then why do hobbyists make them 50% more complex?

My second question is about comets. Of course I got the idea from a video:

https://www.youtube.com/watch?v=WtYvCd7KQkE

The comets they shoot in here are mostly silver or gold. I thought these comets looked ever more nice with the added mine effect.

Question 2: How can you add a mine to a comet? Do you mix the lift powder with the stars and pack in the comet on top of that in the tube?

-Thanks!

[PyroJoeNEPA]

Zambelli's "cookbook" of formulae is a well guarded secret just like any other company making their own proprietary stars & shells. Any time they talk about building, it is in very broad, general terms. Research the net for comp formulas. There are tons available, as well as the standard books by Shimizu & other masters.
As far as the mine/comet effect--it is very easy to do but does require some "tweaking" to get the comet out without blowing it apart:
Put your lift charge in a small baggie in the bottom of the tube. Add a disc on top with holes punched in it for passfire. Add the stars. Add a piece of tissue paper on top of the stars to hold them in place, then put the comet in. NOTE: be sure the comet is primed with a good, hot prime on the side that contacts the tissue paper. Also, put 1-2 wraps of kraft paper or tape around the outside of the comet. You can use painters tape or masking tape, but the craft paper tape seems to work much better. Put a chipboard [cardboard] disc on top of the comet & close the tube. Done!
Let me know how you make out with them. Also, don't get carried away with the lift charge in the first couple you make. Measure & weigh it out & try several different amounts of lift to get the height you want on the comet.

[wizard7611]

Hey, thanks for the replies! I have one question on this though. Wouldn't the lift make the comet go lower than the mine effect since the mine stars are closer to the lift?

[PyroJoeNEPA]

No--the stars are small & propel outwards as they come out of the tube whereas the comet fits tightly & will be pushed upwards. BTW--the tubes for comet/mine combos should be a little longer than a "stubby" for plain mines. Have you ever noticed the commercial "one shot" comets like Ricasa & other companies make are only 35-50 mm diameter, but are 2-3 feet long. That is how hey get the height. Same principle as a rifle. The 1.4 "pro line" comets are only 10-12" long & don't go nearly as high.

[Chris H]

I'd recommend putting the stars on top of the comet instead of between the lift piston and the comet. In this configuration, the comet helps to lift the stars out of the tube like a thick piston. If the comet is on top, you're basically putting the stars between a rock and a hard place. I'm not saying that your stars will be crushed necessarily, but if they are it can turn disastrous (composition dependent).

[PyroJoeNEPA]

I'd recommend putting the stars on top of the comet instead of between the lift piston and the comet. In this configuration, the comet helps to lift the stars out of the tube like a thick piston. If the comet is on top, you're basically putting the stars between a rock and a hard place. I'm not saying that your stars will be crushed necessarily, but if they are it can turn disastrous (composition dependent).
That is interesting Chris. I never did it that way, but will try it & do a comparison. I have had good results with the way I described. Good project for the "hibernating" cold months. I have a bucket full of cedar charcoal from the retort & want to make some comets & BP soon. There is more than one way to "skin a cat". I will try your method. Thanks for the suggestion!

[Chris H]

After thinking about it and talking with some friends, I don't know if it actually matters all that much. The general consensus was that on top will make for a taller column of stars, while below will give a shorter fatter spray. There was a little concern about stars lodging between the wall and the comet causing issues. I always use the star on top orientation for adding a "lift mine" to my shells, and have never really had an issue. I do secure them in a tissue paper bag though, so they at least start away from the walls.