Somewhat 'advanced' question about stars

[braddsn]

There is something I have wondered for some time, and have not actually tested out in the field yet. Here is the question: Lets say I have 2 stars. One is pumped, 3/4 inch, and the other is cut, also 3/4 inch. With the pumped star, I dip one end into bp slurry then into 4fa.. this is how I prime my rising comets for shells. With the other star (the cut star), I roll in prime, priming all 6 sides. Now, in the air, are these 2 stars going to have vastly different burn durations? In other words, is the pumped star going to burn much slower because it is only burning from one end, as opposed to the cut star that is primed on all sides? Hopefully this makes sense. It would seem that the cut star would burn both faster, AND brighter.. whereas the pumped star would burn slower and dimmer. Thanks for any input on this.

[Arw]

2 reason
1.when primed only one side fire must move all of 3/4 inch but all around primed it just 1.5/4 inch then burn faster
2.cut star need more solvent and more solvent give best mix
this reasons make faster burning and more intensity of light

that's what i think.

[flying fish]

That's an interesting question - will the fire "flash over" an unprimed color star? Or will it behave like a wrapped (or wax dipped) comet, burning from one end to the other?

 

Also, geometry plays a role, but I don't know how much. A cube has more surface area than a cylinder of the same volume, and should burn brighter/faster, but by how much? Would it be noticeable?

 

I have a feeling you will have to try it and see. You can take a video and measure burn times in post with a simple (free) video editing program. However, I'd suggesting trying more than the two combinations you suggested.

 

For instance:

one-side primed pumped

all sides primed pumped

one-side primed wrapped (or dipped) pumped

all sides primed cut

one side primed cut

 

Would be a relatively simple test to carry out.

Edited July 25, 2016 by flying fish

[JOPETES]

 

Hello friend Brad. I think I understand your question.

 

This question the answer may very well an arsonist, that is a madman who is dedicated to burn fields or mountains, je jeee, but I'm going to answer myself:

 

If you light a pumped star (eg, a meteor) or a square cut star, one side primed with fast blackpowder obviously the fire spreads from the point of ignition or initiation with black powder to the other end and this process It will take a certain time and the light produced will be providing the burned area, but if the star or meteor preys on the 6 faces or the entire surface of the star or cylinder, fire will prime almost instantly all surface of the star at a time and it will consume all star toward its center or central core providing more light or illumination but the star will be consumed faster since the fire on all sides of the star began almost at once .I hope that answers your question.

foto star primer.pdf

Edited July 25, 2016 by JOPETES

[Arw]

Hello friend Brad. I think I understand your question.

 

This question the answer may very well an arsonist, that is a madman who is dedicated to burn fields or mountains, je jeee, but I'm going to answer myself:

 

If you light a pumped star (eg, a meteor) or a square cut star, one side primed with fast blackpowder obviously the fire spreads from the point of ignition or initiation with black powder to the other end and this process It will take a certain time and the light produced will be providing the burned area, but if the star or meteor preys on the 6 faces or the entire surface of the star or cylinder, fire will prime almost instantly all surface of the star at a time and it will consume all star toward its center or central core providing more light or illumination but the star will be consumed faster since the fire on all sides of the star began almost at once .I hope that answers your question.

that's exactly what i said.

thanks i cant speak english well :-P

 

 

the other parameter can be ratio of surface/volume

for example a cube whit 1cm^3 volume have 6cm^2 surface but this surface for an cylinder is 5.5cm^2

[Merlin]

I am only an amateur but I do have an opinion. I believe the cut star will burn faster and brighter even if primed from one side. Last year I made crossettes that were ramed in the pump. This year I pressed them. Pumped. They burned much longer because the comp density was much greater. The comp in a cut star will be less dense and it would burn faster. In addition the cut star primed on all sides will again burn much faster.

So yes the will be quite different in burn and brightness. The idea behind a pill box star is ignition from both ends and a loosely packed comp causing it to be much faster and brighter. That's my guess.

[braddsn]

Ok thanks for the input guys. I was thinking that the pumped star would probably burn slower, but have not tested this yet.