Rocketry Planet

The 'pieces'

In the photo to the left, you will see all the components necessary to building flashbulb-based ejection charges, with the exception of FFFFg black powder, also called 4Fg, available at most larger gun supply shops, or Pyrodex P, a black powder replacement for pistols called smokeless powder. Pyrodex P is the equivalent of FFFg.

Starting at the back of the photo, you see a graduated measure system by Lee, purchased at a gun supply shop for $8.00. It goes from .3cc to 4.3cc in size. When using FFFFg black powder or FFFg Pyrodex P, a cc is roughly equivalent to a gram. The next line, going left to right, is:

• a package of flash cubes,
• a single flash cube,
• a roll of solid-core double conductor 'zip' wire from Radio Shack,
• a pair of side cutters, and
• a Radio Shack wire-wrap tool.

The wire is black and white and joined together, about 22-24 guage.

The front line, left to right,

• a custom ejection charge construction block, made from a section of 2x4 drilled with 3/4" holes,
• below that a regular candle,
• next is ejection charge tubes,
• and lastly, a hot-glue gun.

Ejection charge tubes?

If you are using flash cubes to make your ejection charges, the perfect tube is the cross-tube from pants hangers. Cut into 2" to 3" lengths, it is a perfect fit. If you are using regular AG-1 flash bulbs, you will need to use larger tubing.

For 2 gram and larger ejection charges, I use regular AG-1 flashbulbs and 1/2" cardboard launch lug tubing. You can use the flashcube bulbs with the larger size tubes to make larger charges, but you will need a spacer to fit between the bulb and the tube. I have used strips of masking tape rolled around the bulbs in the past with excellent results. A short section of pants hanger tube will also make the perfect spacer for using flashcube bulbs in 1/2" launch lugs.

Getting the flashcube apart

Take your side cutters and break into the plastic coating on the flashcube, breaking it apart.

Carefully remove the clear shell and the foil reflector.

Bulbs and the base

This is what you are left with after cutting the plastic shell and reflector off.

Removing the bulbs

Using the side cutters again, snip the plastic base from the outer edge to where the wire leads run through the base, cutting all the way to the wire feed hole.

Do this for all eight wire lead feed holes.

The base will fall apart, leaving only the bulbs with their wire leads.