Little guy rocket engine

[Greg O'Bryant]

Hay guys I went to a gun show and picked up one of these pill fobs for $4.00. The one I got looks just like this one but it is a larger diameter.

http://cgi.ebay.com/ebaymotors/PILL-FOB ... 0602QQrdZ1
Any way I drilled out the stump that hooks to the key ring, so that it has a nice divergent nozzle. I then glued a 1" steel washer to the inside of the nozzle end with some RTV silicone. The washer has a 1/8 " hole in the inside to maintain the throat diameter. Last night I tested it with a single cored, uninhibited grain. It worked perfectly! I wasn't shure if it would stand up to the pressure. I used plumber’s silicone on the threads and a brown paper bag for the case liner. Propellant weight was 25 grams engine weight while empty is 31 grams. The threads did leak a little but not too bad.

I would post a video or pictures but my home computer is out of commission at the moment.

[Mark]

I bought exactly the same model only it has the stainless steel finish. I was at the time thinking it might be/make a fun tiny jam jar but the threads will leak without some sort of high temperature gasket in loo of the rubber o-ring it comes with. But it is nice that it is made of stainless steel.
Mark

[Greg O'Bryant]

Mark try making an engine they work pretty well. I am now on my way to see if the local smoke shop has any aluminum cigar tubes. I'm shooting for the 62.5-gram limit. You should be able to get a lightweight rocket pretty high in the air with just 60 grams of sucrose propellant.:)