Black Powder High Power

[terryg]

Yessir. Flash pan is the only way to go.

Did the flash pan method used have just a layer of black powder or were tubes used to direct the flames into each engine?

 

[DeeRoc29]

Did the flash pan method used have just a layer of black powder or were tubes used to direct the flames into each engine?

A pie tin with an even layer of BP. I've not heard of tubes being used. That sounds explosive...

 

[Sooner Boomer]

An example of using a flash pan for cluster ignition:

 

[SolarYellow]

https://meatballrocketry.com/pvc-spider/

 

[DeeRoc29]

https://meatballrocketry.com/pvc-spider/

I guess it is a thing. Learned something new. Probably not the best method for lighting 50+ motors.

For straight ahead flash pan ignition, one thing @kramer714 taught me before the Pumpkin Pi flight was to coat the pan in a very light layer of grease. The grease holds the BP where you want it if a breeze comes up.

 

[lr64]

A pie tin with an even layer of BP. I've not heard of tubes being used. That sounds explosive...

That would depend, in part, on the strength of the tubes. Anything permanent might benefit from a disposable blow out panel, maybe just paper or cardboard. Maybe you could use drinking straws for tubes.

Fireworks guys have something they call quick match, which is just black match style fuse with paper wrapped around it or in a paper tube. Apparently, the tube makes the fuse inside burn far faster. Black match, as I recall, is just cotton string that's been run through a slurry of black powder, water, and maybe a little dextrin. There are other things you can use instead of dextrin, but it's traditional. Anyway, I think they have the simultaneous launch thing figured out. I could see running quick match from some central charge up into the nozzle of each motor. The quick match could be held in place with a bit of flammable glue. This way, even if the rocket lifted off with only some of the motors lit, the others might be carrying quick match that would light them in short order.

Notice that I didn't say anything about the composition of the black powder.

 

[shockie]

Anybody got a close up shot in slo-mo of flash pan ignition? 4F BP?

 

[Rocketjunkie]

This is how I did it in 2003. Each motor had a short fuse and a few grains of BP. Now I'd just use MJG BP motor starters in each motor.
Clear packing tape covered with BP and Estes starters to light the BP which lit the fuses.