: >
: > I have some motors from the late 60s, that still function fine. I suspect
: > that C.D. does also.
: >
: The critical factor is: where did you keep them? If they were in an attic
: or garage I suspect they have heat damage. What happens is the solid fuel
: grain expands under heat and permanently presses the casings out. When
: cooled to normal, then grains contract but the cases don't - leaving a
: gap between case and grain. The instant the burn front reaches the case wall
: the rocket engine becomes a roman candle. The rest of the grain gets barfed
: out the front of the motor & you have a little bolide. Not to mention a
: roasted-out recovery system.
:
: If you kept them in an air-conditioned bedroom or other controlled
: environment they may be fine.
I have stored them in my garage, under a bed, in a spare room etc. They are
all B or smaller, and I have never had a problem with any of them. I have
encountered temperature cycling problems only on D motors - not on any that
are smaller.
: You can probably test one by burying it nozzle-up so that the nozzle is
: flush with the surface & then static firing it. If it doesn't "shoot the
: moon" the rest should be OK.
As I stated, they work fine. Of course, I am reluctant to use up such old
collector's items.
Bill