Brittle Phenolic tubing Unless you intend to fiberglass it of course.

Copper Igniters Keep the pyrogen, ditch the copper leads.

Elastic Shock Cord Belongs in your underwear not in your rocket.

Deep sea fishing swivels. Even the 800 pound test ones, should be used for fishing, not for rocket recovery. (Courtesy of Bruce Gregory)

Eye Bolts Unless you weld them closed.

Hot Glue (We love you Bubba)

Altimeters that use small lighter batteries. (Good luck)

Friction fit motor retention. Unless youre flying D-motors, forget it.

Certifying with a slow burning motor If it's a Cert. flight, it just won't light.

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