I used to use the aluminum screen clips you mention, but after a failure, I
switched to fashioning my own clips from hobby brass strips. I'm happy with
them. Avoid the aluminum screen clips. -- Richard "been there" Hickok
In my opinion the aluminum units are too brittle and may fail in particular
if there is a strong ejection charge.
The Steel mirror Z clips on 8x32 or 10x32 stand offs are stronger and
cheaper than the aluminum.. they do need replacing from time to time but a
69 cents for 4 not a big deal..... I use 4 , I HATE to loose HW.........
I have a pic of a rocket set up with these... I can send it to you if you
At one launch, I found I didn't have clips for a RMS case, they had all been
bent for single use motors (with wraps of 3/4" masking tape). My clips are
made from picture hangers (1/8-1/2" wide) which are very difficult to bend.
So in a pinch, I used spent igniter wire to wrap around the two screws and
over the motor. Worked like a champ.
Brass picture wire also works well, and is available is several guages. It
works great as a spur-of-the-moment retainer, or as a planned retainer for
odd or difficult situation (like a motor adapter that sticks out a long
The screen door clips are much too thin. I make my own, similar
to the clips to which you refer... I use 12 gauge aluminum strips. Clamped
and bent with a pair of Visegrip locking pliers. You can see an example of
my work on page 53 of Mark Canepa's Modern High Power Rocketry. Install
tee-nuts inside the lower centering ring, and bend the clips. Then hold the
clips in place, and mark them for the screw holes. Drill them, and you have
very reliable motor retention. I have yet to lose a motor, even when using
very energetic ejection charges.
James L. Marino
SAS, SARG, LUNAR,
NAR #75764 L2
TRA #9489 L2
"Ban light pollution, not rocket motors."
Thanks all. For the record, I've almost always used brass strips and have
never had a problem. Based on your collective comments, I think I'll stick
with it. I've successfully used mirror clips also, but they tend to corrode
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