Quantcast

MMX motors as spin rockets...

The Rocketry Forum

Help Support The Rocketry Forum:

Mugs914

"A crummy commercial..!!??"
Joined
Oct 1, 2012
Messages
1,222
Reaction score
793
Location
Temple TEXAS
I hope this isn't too dumb of a thought and I also hope it doesn't appear as a blasphemous use of MMX motors!

Have MMX motors been used as spin rocket motors on a larger rocket? Several full size rockets such as the x-17 and Doorknob (I think) used small motors to initiate spin just after launch and I thought this might be doable using MMX motors on a mid-power scale rocket. Of course it would require some type of timed ignition, but that is very common these days. Would be a pretty neat scale touch, I think!

I have to admit that I have ZERO experience with MMX motors, ignition etc. so there may be a hundred reasons that this is totally silly idea. But you never learn if you don't ask, I suppose.

Thanks!

Mike
 

dhbarr

Amateur Professional
Joined
Jan 30, 2016
Messages
6,708
Reaction score
1,216
I would think that if one wanted any sort of practical effect, something like the d2.3 would be much more useful.
 

Micromeister

Micro Craftman/ClusterNut
TRF Lifetime Supporter
TRF Supporter
Joined
Jan 19, 2009
Messages
15,074
Reaction score
42
Location
Washington DC
I hope this isn't too dumb of a thought and I also hope it doesn't appear as a blasphemous use of MMX motors!

Have MMX motors been used as spin rocket motors on a larger rocket? Several full size rockets such as the x-17 and Doorknob (I think) used small motors to initiate spin just after launch and I thought this might be doable using MMX motors on a mid-power scale rocket. Of course it would require some type of timed ignition, but that is very common these days. Would be a pretty neat scale touch, I think!

I have to admit that I have ZERO experience with MMX motors, ignition etc. so there may be a hundred reasons that this is totally silly idea. But you never learn if you don't ask, I suppose.

Thanks!

Mike
Since Micro motors are a full inch long and the general configeration of the Spin motors on Vehicles like the X-17, Hojo and Doorknob and others are usually thinish discs most of the MMX motor would have to be enbedded in the body of the vehicle meaning the rocket would likely need to be at least BT-60 or larger. Not to mention getting the motor(s) canted enough to actually cause a spin. Possibly some sort of right angle thrust vectoring might work, although I've had MMX-II motors burn through a 20ga stainless steel deflector plate. Then there is the short duration of MMX-II motors, with only about .8 seconds, I doubt they would be much use as a spin motor on a scale model of the size needed for any of the vehicles listed above.

That said there have been a couple micro models designed to Spin up on launch with either a single or two motor cluster as seen below. EXTREMELY fast off the pad and very high spin rate, but due to aerodynamics come in pretty fast also. Not very dangerous but require heads up before flights and Launch rod positioning down range just to be safe.
The single and twin motor MM Whirlygig and twin motor Christmas Holly Wreath are all designed to spin up and down. but only the twin motor Whirlygig and Wreath actually use canted motor mounts.

MM 309p1-sm_MM Whirlygig-a Odd-Roc_07-14-05.jpg


MM 309p2-sm_MM Whirlygig-b twin motor_07-15-06.jpg


MM 310a1a-sm_Micro SpinRing Thing_07-23-05.jpg


MM 310a2a-sm_MM SpinRing Thing 2-motor_07-30-05.jpg


MM 310b-sm_MM SpinRing Thing 1-motor_07-28-05.jpg


MM 394_Christmas Holly Wreath Glittered (Lit)_12-01-13.jpg


MM 309pf1d-sm_MM Whirlygig twin motor 5 pic Pg_07-15-06.jpg


MM 310b-Lp10b_Micro SpinRingThing Ignition (Pic by DaveFuller_10-19-13.jpg


MM 394Lp01b_HollyWreath LiftOff 2-mmx cluster_12-21-13.jpg
 
Last edited:
Top