Empty MMX Casings, Anyone?

[orbitboybob]

That's quite the idea for a way to extend the delay of these things.

But.... I don't see the NE motors on the Quest web site any more. I think I may have four left of the one purchase I made. I would love to try your idea.

BEC -
Thank you for your feedback!!!
Certainly, I would not be so bold as to suggest modifying an MMX with 1 sec delay into a 0 second booster because, it is not necessary. While not fully tested (yet - in process) it should be possible to add "the package" to a regular 1 sec delay MMX motor and achieve similar results.
I'm pretty certain the technique would work with larger (booster) motors if the package were scaled up. However, due to the clay cap on the larger motors with delays, I am uncertain at present whether delay extender packages could be added to them and still retain full function.
That will require a little more time and some "playing around."
-- Bob

 

[BEC]

Bob,

I eagerly await your results with the regular (not NE) MMX motors. I will have to think about how I'd mount such a motor with the added delay as (I think) all my MMX models have a motor block. But I wouldn't be averse to building new ones to take advantage of this idea.

 

[kuririn]

My understanding was that the NE motors still have the delay, but no ejection charge.

 

[orbitboybob]

I heard in idle conversation, not very long ago, that there were suposedly enough MMX motors "out there" to last everyone who wants some for years. How true that is, I don't know. There certainly seems to be a lack of them through most vendors, and as far as I can tell, most all that are available are 1 second delays on the Aerotech site. Finding your situation similar???

 

[kuririn]

As far as I know all the MX motors are 1 second delay.
Erockets has 44 6 packs in stock.
https://www.erockets.biz/quest-moto...-for-ground-advantage-or-ups-ground-shipping/

 

[BEC]

NE motors are (or were, since they appear to be no longer available) just that — MMX motors with no ejection charge. But they do have the about one second delay.

That delay is too short for anything but the Quest plastic bricks. Everything else ejects going up at a pretty good clip, or at least that's been my experience, even when I made an MMX model big enough to carry a FS Comp altimeter.

The regular motors are available from Quest in 6- and 25-packs and the six packs are available from ASP, eRockets, jonrocket.com and I expect some other places as well. But I haven't found anyone with the NE motors anymore.

As I understood it, they were standard motors that had their ejection charges manually removed. I can see why that would not be a high-volume product in any case.

Staging with NE motors in the booster gives delayed staging, which is actually quite cool when it works.

Dr. Bob's technique to lengthen the delay (as described in his article in post 22) opens up some intriguing possibilities.

And yes, Gary Rosenfield has remarked on more than one occasion that they still have a huge supply of MMX motors. But I expect (though I have not asked him) that he's not too excited about making more NE motors from some of them. Maybe someone can ask him about that at the Q&A at the end of the virtual tour at vNARCON on Friday.

 

[orbitboybob]

Here are some photos that may help clarify what is going on in the MMX-NEs. There is an obvious depression in the center top of the motor with no real indication on the upper inside wall that any material (or ejection) has been drilled out. I believe the motors are simply filled with BP.
The second image is a Dental Xray of the same 2 motors. I can see the compression bands from when the motors were sequentially pressed (3-4 times). There is absolutely no difference or gradient change to indicate different materials or layers. The clay nozzle is evident in the bottom 3mm with 3 to 4mm of extra clay along the wall above it from being pressed. The second xray has these areas marked off with red lines.
I suppose MMX-1's could be modified by drilling them out as Kuririn suggested, but that would constitute "tampering" with the motor. I would prefer to develop a simple plug-in add-on package so this is not necessary. I have not yet tested the idea of adding on to an MMX-1, but that is the next step.
Luckily, the extended delay only increases the length of the motor by 4-5mm. It is light enough that it would not effect CG/CP locations detrimentally. I think it could be made to fit entirely within the top of an MMX-NE, but I doubt that would be possible on the MMX-1. However, this present configuration may be adapted for both NE and 1 sec MMXs.
I'll need to spend a little more time in the lab after vNARCON. Are you guys signed up???

 

[orbitboybob]

BEC --

What if we were to tell Gary about this thread (at vNARCON)? You think he might consider the
idea a little more seriously?
Unfortunately, I got locked out of the forum - it was completely filled.

 

[BEC]

BEC --

What if we were to tell Gary about this thread (at vNARCON)? You think he might consider the
idea a little more seriously?
Unfortunately, I got locked out of the forum - it was completely filled.

I don't know, but I kind of doubt it. I asked about more NEs in the Q&A after the Aerotech this afternoon and Dane Boles basically said they would really prefer if someone else actually took on MMX motors. They have lots, but they have no plans to extend the line. I don't think he even knew that these NE motors previously existed. And Gary certainly didn't contradict that.

With everything else that they are doing being composites, I can see that these tiny BP motors are not a good fit with their product line. I expect that if you go to the recording of the Q&A you can hear that answer for yourself.

I did NOT volunteer to take over the MMX motor sales/distribution, though.

I'm not sure where to go from here.

 

[kramer714]

Micromaxx motors - give away....

I have
(1) unopened 6 pack of '120 foot max altitude (blister pack)
(1) unopened 3 pack of '120 foot max altitude
(1) unopened 4 pack of '200 foot max altitude
(1) opened with (2) '100 foot
(1) opened with (2) 200 foot

These are free to a good home (somone that will actually fly thrm not keep them or sell them)

Im in Orange County CA

Mike K

 

[ep29030]

RocketShip Games has MMX motors as well.

 

[ep29030]

If anyone is interested in making a MMX-based V-2? Balsa Machining sells a nosecone/tailcone for the old Apogee Medallion motors (10.5mm). It is drilled out through the tailcone and part way into the nosecone to fit a BT-4 tube (which was the motor tube for the Apogee Medallion motors back in the late 90’s). Buy the tailcone/nosecone set from BMS, add a 2” piece of BT-20 for the airframe and a short piece of BT-4 for the motor mounts and either buy BT-2 to BT-4 centering rings or make them from glue stick and paper strips. Print the Estes V-2 fin pattern sheet (Jim Z website) at 56% scale. Add a BT-2 motor tube (1” long), a BT-1+ tube for a motor stop block, kevlar cord and you have basics for a MMX V-2 kit. Just started one. I’ll post pictures when I get a bit further into it. Airframe total length is 6”. I am looking at either 1/32” basswood or .020 styrene for the fins—may cut a fin from each material before deciding which way to go, as each has benefits and drawbacks.