Spolletes for rockets

[MrCATO]

My new toys finally arrived from caleb. I got some spollete tooling to fit shells onto my 8oz (cohete) tooling complete with end discs. The thing is before I just pressed in a delay charge after the spindle portion because I was using those snug fitting heading tubes for flash. With these 2.5" new heading tubes I got it requires me to change the construction method. Instead of the heading tube ID being snug enough to fit over the rockets I put on discs and glue the end of the rocket to the bottom of the shells. 

I've got printed out a few charts from skylighter about shells and in particular the section that says I need a 5/16 id .55 od 2" spolette with 1" powder charge for a 3" single break shell. These tubes are 2.5" OD that when I get bigger tooling will be used for bottom shots but for now will just be the entire heading. I'm also watching ned gorski's video on making spolettes but his video seems to imply mortar fired shells vs rocket carried ones. It would seem a bit redundant to ram a delay increment and have a time delay spollette at the same time but I obviously need the spollete to fit the disc on these in order to secure these bigger tubes on my rockets. Do I just ram a clay bulkhead instead of a delay charge to pass fire to the spolette? Or do I ram a delay as I normally would, but leave the spolette tube empty? I obviously can't leave the spindle increment uncovered on top of the motor otherwise the gasses for lifting the rocket would come out of the top of the motor lol.

My first attempt looks a little wonky, probably pressing too hard. 

 

 

 

 

Edited June 4 by MrCATO

[DavidF]

I just use the rocket's delay, like you did. There's no need for a rammed spolette. What I would do in your situation is put black match in the spolette tube, folding it over and taping it onto the shell end of the spolette tube. I'd leave enough hanging out the bottom of the spolette tube to touch the top of the delay, kinking it over if necessary. You might want to wrap some tape around the motor end of the spolette to bring up the OD so it has a friction fit inside the motor tube and then glue the shell on, but don't use so much tape that it has to be forced on. That's one way to do it, I'm sure there are others.

[MrCATO]

I got some more chems on the way, I won't be able to make black match slurry until I get my dextrin. Never tried it before. For now I tried with some fuse I had laying around. I ended up putting a little bucket of foil temporarily over the spollete to contain any flash that might fall out while spiking. Seemed to work well. I couldn't get the motor all the way flush with the shell given the accumulation of string at the base of the spollete but I suppose that doesn't matter given that bringing the OD of the spollete to the ID of the motor like you said worked well in mating the shell/rocket.

Thanks for the advice, even if the spollete tubes are empty the construction of the whole thing feels better than the way I was doing it without.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited June 5 by MrCATO

[pyrokid]

Another concept is to fix a short length of larger tube over the motor on the heading end in order to provide more surface contact between motor and heading.