Model Forum / General / Rockets / December 2005

Paul,

If you bought an Aeropack retainer, then you're going to need an Aeropack
54/38 adapter to fly 38MM loads.  Giant Leap makes Slimline 54/38 adapter
that works with Aeropack retainers as well.  I have an Aeropack 54/38
adapter.  Very nice quality stuff.

The Aeropac retainer is two pieces.  The first part is epoxied (use JB
weld) to the back of the motor tube, and has an external thread.  You
may need to sand the motor tube for a proper fit, so this is often done
"first".  If you've already epoxied the motor tube in place, test fit
the adapter ring before you go farther so that you can sand as needed
with fewer pieces in the way.

Once the retaining ring is in place, the other piece screws on in order
to retain the motor OR adapter.  The 54-38 adapter consists of TWO
pieces, one is a 38mm-sized inner tube with a flange at each end that is
sized for the 54mm tube, PLUS a specially-shaped ring.  The ring is
placed over the aft-end of the adapter after it is put in place, and
'fits' into the screw-on part of the retainer, so that there is
absolutely no shifting of the adapter, and there is tight retention of
the 38mm motor.

I don't use anything other than AeroPac retainers -- they're not cheap,
but they work OH so well...

David Erbas-White

I personally don't buy anything from a company that can't write instructions
or descriptions (eg, BlackSky).  I'd get the Giant Leap retainer and adapter
instead.

-- David