The MM 1 adapter is simply a cardboard tube with an outer diameter of 29mm
and an inner diameter of 24mm.
Friction fitting motors is a process whereby you wrap masking tape around
the 24mm motor typically in a spiral configuration. The trick here is to
make the motor slide tightly enough into the MM 1 that it will not be
expelled during the ejection charge stage but not so tightly that you cant
get it back out later. If the 24mm motor you are using does not have a
thrust ring you also need to build one up on the nozzle end using several
wraps of masking tape.
The next step is to friction fit the MM 1 into the rocket. This is
essentially the same method also utilizing the thrust ring wraps. Remember,
as the motor burns it heats the tape which also increased the amount of
friction between the motor and the adapter.
An alternate method is to simply slide the 24mm motor into the MM 1 as far
as your thrust ring will allow and tape that ring to the end of the adapter
with several wraps of tape. If I am using one of the longer 24mm motors
that extends beyond the length of the MM 1 (such as a G55 which will make
that Aura beg for mercy), I just run a few wraps of tape at the other end of
the motor as a kick ring. The addition of motor retention clips is quite
popular and easy to do. Personally, I have rockets with and without and
have only had one motor kick out. The one time it did kick out was on a
cluster of D12's. When they all expel their ejection charge at once the
weak one sometimes goes - even with many wraps of tape.
Good luck - you will enjoy flying this one on D,E,F and G motors - (some H's
can pull the fins off by putting more pressure on the cardboard laminations
than they can handle - my Onyx lost a fin on an H180 the other day). If you
go bigger, I would add some fiberglass or use a single use motor. I think
this was the original "mach buster".
Barry E ***
NAR#76085 SR L2 TRA# 7961 L2
> Just got through finishing this kit, My question is about the MM 1
> adapter, Can someone explain how it works, Will this enable me to use
> BOTH 24mm & 29mm engines?!? Has anyone had problems with friction
> fitting motors with this kit? I loved putting this kit together and will
> probably buy a couple more in the future, I've read all the reviews on
> Essence's page and seems like this
> friction fitting wasn't a big issue. Any thoughts?
> Thanks, James.............................