crackling fountain

[ronmoper76]

I can not make a fountain work with crackle mix unless its nozzleless and made with whistle. I have tried several different formulas with a nozzle and crackle mixed in with the fuel,either the pieces are to small and burn up before they exit the nozzle or the larger pieces blow up the fountain. Before i had tooling i used whistle mix and my short rammer for rockets,blended in the crackle,pressed it full and it worked great but i wanna learn some more tricks.. I haven't bought any yet,but i wondered what 30-60 mesh magnalium would do in fountain mix,would it give a similar effect?

[mabuse00]

Does your tooling have a convergent rammer?

 

When I tried coarse MgAl grades in fountains some 20% where expelled, the rest formed a large blob of slag before the nozzle and never left the tube.

I found a convergent nozzle helps, but does not fully cure the problem.

 

A propellant of high burnrate might also help, getting things in motion quickly before melting(or in case of DEs burning away) occurs.

 

I've always been cheap with fountains, wasting good milled BP - no way. But in some way, using greenmix seems to be part of the problem.

Edited May 6, 2021 by mabuse00

[ronmoper76]

Does your tooling have a convergent rammer?

 

When I tried coarse MgAl grades in fountains some 20% where expelled, the rest formed a large blob of slag before the nozzle and never left the tube.

I found a convergent nozzle helps, but does not fully cure the problem.

 

A propellant of high burnrate might also help, getting things in motion quickly before melting(or in case of DEs burning away) occurs.

 

I've always been cheap with fountains, wasting good milled BP - no way. But in some way, using greenmix seems to be part of the problem.

yes my tooling does,its a 3lb set from woodys. And i think your theory holds water because it works well with a high speed propellant like whistle fuel. I guess i need to search for some hotter fountain formulas.

[BetICouldMake1]

I'd guess getting the size relative to the nozzle right would be the trick. How think you prime them is probably important too. I would think small pieces with thickish prime would would help give them time to exit before popping.

[SKC]

You may consider the following points to make a crackling fountain successfully. Seems your crackle particle have no issue of catching fire.

 

Crackling particle sizes.

Crackle percentage to BP.

Nozzle id

Hardness of the nozzle.

Base BP ( It shouldn't be too fast or too slow).

 

There are people who make crackle fountain without any tooling. So cheers.

[ronmoper76]

I actually tried everything under the sun but BP,LOL Its still work in progress

[Twesla]

Hello, Ive been lurking on here for the last year or so, as I just started doing pyro as a hobby early last year, at the tender age of 35. I dont have the experience that most people do on here, but I can tell you that I had the exact same problem when I tried making crackling fountains. I had positive results using meal with ball milled charcoal for tweaking the burn rate, but what helped the most was using only the micro stars that are 2mm or less in diameter, and priming them with a generous portion of hot prime. I used NC lacquer thinned out enough to be sprayed, but Im sure an alcohol or water bound prime would work fine as well. I hope this helps!