Having had two rocket with payloads not work in one way or another, I just had to try something a little more ambitious.
I made up a 20 mm canister shell, 3 turns of pasted A4 80 gsm paper. One end was closed with wadding and a triangle fold.
A 'flash bag' was made using a plastic drinking straw, sealed at one end with hot-melt glue, then filled with -20+40 mesh pulverone. A length of meal-NC fuse was then sealed into the other end with more hot-melt glue. This tube was then hot-melt glued into the centre of the canister.
I raided a mine I've been meaning to shoot for the stars. They were a collection of rubbish that didn't work in one way or another, mainly charcoal streamers and Aluminium flitters. I corned a few in the mortar and pestle, then sieved out the smaller junk. The broken bits were packed around the break core and a teaspoon of -40 pulverone was shook into the intersitial spaces.
The top was then folded around the fuse and pasted. There were no disks used at all. Next, the shell was spiked with the cotton string I use for my blackmatch, not ideal, but it was all I had. Finally, the shell was well pasted and over-wrapped with more A4 paper.
A rocket motor was prepared, exactly the same as the two that had worked so well eariler. I carefully ensured I had fully drilled through the bulkhead this time, the drill flukes bringing out a little propellant. Some +20 mesh pulverone was placed on top of the bulkhead and shook down into the passfire hole.
The fuse on the canister shell was folded over and cut to a 10 mm length (about 1 second). The ends were dipped into meal-NC paste and then plunged into the pulverone in the top of the motor casing. A bead of hot-melt glue was used to attach the canister firmly to the rocket motor.
The motor was then finished off, the stick added and fused in the usual manner.
Worked Great!
Considering that the shell weighed more than than four times what the motor did, the rocket did and excellent job of lifting the payload to a good height (about 50 metres).
The seperation charge produced a small puff of sparks and shortly after the canister shell broke. Not much of a break, and the stars were pretty lame, but not bad for something made from junk materials as a quick test.
I think a shell full of my D1 glitter stars would look great. If anything I probably over-spiked the shell. It definately needs better end strength and weaker walls. Letting it dry more completely in the future definately can't hurt either.
| title | type | size |
|---|---|---|
| Test Video | video/x-msvideo | 614.392 kbytes |
| Pre-Test Picture | image/jpeg | 45.860 kbytes |
| Shell During Spiking | image/jpeg | 43.004 kbytes |