Sep 20, 2025

Ejection Charge Well

This is a design I have been iterating on since 2018 and have finally arrived at a simple and repeatably reliable system.

The models are published on Printables The design uses standard 1.5mm centrifuge tubes to hold the black powder/pyrogen and efficiently have the igniter head at the base of the charge.

Snipping the bottom off the tube allows the igniter wire to thread through the base and out the side of the well.

The charge well uses brass screws and knurled inserts to connect the igniter wires to the internals of the ebay.

Charge Well Loaded
Charge Well with Tube

These images show the charge well in action with the Baby-T rocket. The after-flight image shows the charge well after use. For this flight, only the primary was used leaving the secondary empty.

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CAD Models

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