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Deployment Charge Holder
We've been using these deployment charge holders for a long time. They're not an original idea, we found them on Robert DeHate's Tips site and modified them a little. We also used some of his sketches for which we owe him credit. We make cardboard units for normal flights and brass units for high altitude use. These charge holders work really well for BP charges up to about 2g.                 Brass charge holder

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 These holders are easily made with inexpensive parts. An electric match is soldered to a cable TV connector. The assembled connector is glued into a brass or cardboard container. The holder is then loaded with BP and capped. These holders are compact, storable, easy to install and very reliable. We have tested the brass units in vacuum chambers up to 100,000'.

                    Connector detail

          

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We make the charge holders using a Cable TV type F terminator. Belt sand the tip to remove the internal resistor. Strip a short section of cable and epoxy it into the terminator. Desolder one wire from the electric match and solder it to the tip end of the connector, Solder the other match wire to the connector body. The above photo shows loaded charge holders installed on the bulkheads of the Avionics bay for our dual deploy Firestorm 54. Also shown are the power slide switch and access ports for the Blacksky AltAcc2C. The ports allow access to the safe/arm switch, viewing the status LED and compartment venting.  Above is the bay partly disassembled showing the internal connection to the panel mount connectors. F couplers can also be used, but they're a little short to fit through many bulkheads and require a second connector on the inside.
           ChargeMounted.gif (3903 bytes) The finished connector can be epoxied or hot-glued to a length of the cardboard tube from a clothes hanger. For high altitude use, we epoxy the connector to a .45 Colt cartridge case after drilling a .25" hole in the primer end. The measured charge of BP is then poured in and held in place by a cotton gun cleaning patch. DO NOT use recovery wadding as the fire retardant will degrade the BP. We cap the cardboard charges with masking tape and close the brass charges with .38" vinyl cap plugs. FF Avbay.JPG (137938 bytes)    Charges can also be built with the correct length of match wire for single deploy use. Our Firefly uses a charge with 36" of wire allowing the charge to be placed aft of the parachute. The D-9 connector allows easy download of AltAcc2C data from outside the Av bay.