Troubleshooting some 1lb rockets

[AzoMittle]

Hey all,

 

I'm starting to plan and get ready for the next club event. Planning on making less but hopefully better, thinking of sticking to a few 12 inchers, a handful of 8"s, and some 1 pound rockets. I was very happy with the 12" I built last year (though maybe a little more lift this time around ;P) but I was rather unimpressed with my rockets. They had a nice tail and they did fly, but not very far, fast, or well. That was my first time making them so I was simply pleased they didn't CATO on me.

 

Anyways, hoping to kind of troubleshoot what I did wrong and how to improve. I unfortunately do not have any video, I try to enjoy myself while on the line instead of dealing with cameras and staring at my phone screen, etc.

 

They were 1 pound, bentonite nozzled and cored rockets; I was given some of those small Chinese festival balls by a friend, glued them to the top. Used the tubes from Phil's General Store cut to 7" lengths. For a stick I used square wooden poles I begged off another friend who was making rockets, don't remember exactly but I think they were 36", not sure.

 

The rockets were hand rammed on a concrete base with a (not dead blow) rubber mallet (my first mistake, I know), at 1/2" increments (I don't remember exactly how much it was but IIRC around 1 tablespoon of comp). The nozzles were rammed in a single go though based off the instructions that came with the rammers.

 

The formula for the fuel came from Alan Yates. He has a standard fuel and a hotter fuel, he says to start with the standard and make it slowly hotter as needed. I used 2 parts of his standard to 1 part hotter, as per his instructions I ball milled thoroughly, moistened lightly, pressed through a screen and dried (I believe this is just to help cut down on dust, may be wrong though). He does call for a small amount (5-7%) of atomized dust aluminum, which kind of worried me with the hand ramming, I ended up using a combination of equal parts firefly flake, Alcoa 120, and German Dark. The FFF was to give a nice tail and the the GD was to help make it hotter, the Alcoa is a mixture of fine and coarse so it was supposed to help a little with both, some variety.

 

STANDARD HOTTER FINAL

KN.....18 (62)..................68..................64

AFC...06 (20)..................17..................19

Sulf....03 (10)..................10..................10

Al.......02 (07)..................05..................06

 

I have a sneaking suspicion I need to use a hotter fuel and then have a separate section with the Al tail at the end. I know I need a dead blow mallet. I cannot afford a rocket press now or anytime soon unfortunately; as such, I would like to avoid metals if there is a realistic chance of possible injury, at the same time I really want a tail but I'm not a fan of the charcoal tails.

 

While on that topic, has anyone made a rocket fuel that uses lampblack or a glitter?

 

edit: Oh, also, is there a good way to seal up the nozzle temporarily? Could I say, dip it into wax?

Edited May 23, 2017 by AzoMittle

[lloyd]

Some practicioners add wax and/or graphite to the bentonite, in order to make them more erosion-resistant AND improve their stability in humidity.

 

There were several articles to be seen over the years. There were some in AFN and two or three mentions of it in the PGI Anthology. I believe there were also a couple in volumes of Pyrotechnica.

 

Lloyd

[pyrokid]

With the limitations on consistency that come with hand ramming as opposed to pressing, I'm not sure that the more exotic fuels are worthwhile (and worth the cost!). You can lift 3" cylinder shells all day on hand rammed traditional 1 lb rockets using simple 6-3-1 as your fuel.

 

A general rule of thumb for tube length is 10*ID_tube, so 1 lb tubes are usually cut into 7.5" lengths.

 

Metallic tail compositions can be pressed above the spindle to give the rocket a tail. Another option is to secure a simple gerb or even a puck of composition to the exterior of the rocket and ignite it at liftoff. There is some debate about the safety of hand ramming metallic compositions but that is a separate issue.

[OldMarine]

I've taken to leaving the nozzle out and using the hottest fuel I can make even adding 25% sali whistle to the mix without a CATO so far. 70/20/10 screen mixed was the hottest I've used for a nozzled rocket and over half blew on the pad. I use my rockets for a header delivery system for the most part rather than a standalone effect so I'm not concerned so much with a graceful rise as with an assured altitude. Rockets sure are some fun!

[AzoMittle]

Ooh, thanks OM and PK.

 

There's a snowball's chance in hell I'm touching sali rockets without a press but I will try out the no-nozzle 7-2-1 mix. You said you screen mix yours, would 'ballmilling' very briefly work you think? I bet it would.

[OldMarine]

I ball mill the fuel for the nozzleless rockets and just screen mixed fine chems for the nozzled ones.