advice needed: changeable MMT removal

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Well-Known Member
Sep 12, 2002
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I am working on a scratch built rocket with interchangeable MMT.
So far, I have partially assembled the 3X24 mount. The fit is a little tight, and will be even more after firing. So my dilemma is: how can I devise a good way to non-destructively pull it out post flight?
As you can see, I will have a BT70 coupler going inside a BT80. I need some help both on extraction and motor retention.
Here is a picture of the two parts separately, and with the MMT partially inserted:

Warning: I didn't scale the pixels down on these


Hi Eric,!
heres how I've done it before,
If you have the stuffer tube large enough diameter for a broomstick or dowel to fit thru , than you can tap it out from the top of the BT,, it will help if the contact point on the motor mount cartridge has an area of epoxy where the stick will hit,,

if you don't use a stuffer ,obviously the same idea will work

ok now fess up ,,what you building?!
Hey, I like that! Simple but effective-- why didn't I think about pushing from the other end? Seems obvious now!

OK, I have an old Fat Boy nose cone, and I bought some heavy BT80. So I am cooking up some kind of extended Fat Grandaddy, I guess ;) . I can use a two or three engine 24mm cluster right now. AND, I just remembered I have some spare 29mm MMT, too!

Yeah, I am thinking F20-7! :p