Lightest Mini Magg possible

Probably would be simpler to just get an L1.

yep - minimal wood glue for sure - the little saw kerfs around the edges of the centering wings will allow really good purchase with very little glue

Also... keep in mind that you may need to oomp up your ejection charges. That is a significant amount of volume to have to bang out... Not sure if the charges that come with the motors will be sufficient.

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To save nose weight: remove bulkhead, then attach strap to side of cone with a piece of FG cloth and epoxy. To keep chute from entering cone, add a 1" thick foam bulkhead (pink rigid foam) at base of nosecone.

Since this won’t be flying or accelerating very fast you could shorten the nose cone shoulder further. Also the ones I’ve cut tended to be pretty uneven on the thickness, some creative sanding or router work could shave a few grams removing the excess plastic inside. Next would be put the whole nose on a lathe, spin it up and sand the OD to reduce the thickness slightly.

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the foam bulkhead idea is great - i will be looking into that for sure

wow - crazy triple post from me - sorry guys - my browser was acting odd and i was unable to see that my posts made it

And yes, I agree it would be simpler to just get L1
I am enjoying this challenge though and this way i would not have to buy 38mm stuff (yet)

I used to have a stock Mini Mag bag around 2000. I think I may have flown it on a G80 or G64. It was built stock and before the locking fin tabs. Probably flew to around 500 foot.

Brent said:

I used to have a stock Mini Mag bag around 2000. I think I may have flown it on a G80 or G64. It was built stock and before the locking fin tabs. Probably flew to around 500 foot.

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Certainly, the Minie Magg has morphed a bit over time. The fin shape, thickness, thru tabs, recovery components, nose cone thickness and weight, etc.

CoachSteve, I'm enjoying watching your build, as the "lightweight" factor is probably what I enjoy most about paper rockets. Minie Maggs are a personal favorite, keep up the good work!

I have somewhere between 3 and 5 Minie Maggs...they're somewhat transient in my fleet. I'll give them away, pick them up, rebuild 'em, my Dad will give mine away, etc.). My oldest two have the "original" fin shape where the trailing edge has some aft sweep. 1/8" 5 ply fins, rings, light recovery gear: these two fall under the 3.3lb limit even with 38-2G H motors; I fly them all the time at Class 1 launches. My newer Maggs weigh more due to stock material changes (not different build techniques) and therefore can't be flown at Class 1 launches. My preference is the older, lighter Maggs.

I myself was thinking of doing a Mini Magg lite weight. How are the fins done on the new Maggs? Still using the fin lock system?

Could save a little weight by going with single use 29mm instead of aluminum reload casings. Could eliminate motor mount tubes and size rings to fit motor OD. Wood glue instead of epoxy (and sparingly!). Dry cleaning bag material for parachute.
-Ken

I will see if I can answer a few questions
The newer Minis come with 1/4 inch through the wall fins (LOC cannot even make the older style) - about the 10th post has a pict of the stock fins.
My build is not using motor tubes - the centering rings are sized to just accept the motor cases -(second post has a pict)
I could fly it on one 29mm but then I would ave to scrap my 2x29 idea and rebuild the centering rings (I really want to avoid this option)
I could use single use 29s but I have the RMS hardware and reloads
If I get some time I will post up my current weight - after the nose cone work and maybe some more sanding on the rings and fins

Do you have access to a router that can round over a bunch of square edges? It's not much, but I'd bet a half ounce or more.

new2hpr said:

Could save a little weight by going with single use 29mm instead of aluminum reload casings. Could eliminate motor mount tubes and size rings to fit motor OD. Wood glue instead of epoxy (and sparingly!). Dry cleaning bag material for parachute.
-Ken

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Single use= less weight,
good idea

I have already routed the edges of the fins - I will look for more opportunities

Bevel the edges of all three fins. That will shave off a little more weight.

CoachSteve said:

I have already routed the edges of the fins - I will look for more opportunities

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Did you route the interior edges of your open ring? :-D

do you need the fin lock interior cross pieces, or even the fin tabs? how about cutting the fins flush with the ID of the tube relying on adhesion on the body tube and slots. Also, the mid spar on the fins, removing it and using balsa for the all the interior portion would save weight.

can you do without the two outboard motor retention pieces, seems like the central one covering both motors would suffice

last resort, "speed holes", cutting holes in the body tube and covering the holes with fancy speed stickers / vinyl that can withstand the ejection charge.

Thanks for all the suggestions guys - I will get out the old router -

Well - short of scalloping the tube all to heck (which I didn't want to go that far) - it turned out real pretty. Still a bit too heavy though for 2x29.
I make weight if i fly it on one 29mm though
In all it was a really fun project that I think turned out quite nice.
It will be great to see this guy go up, and who knows, this may just inspire me to get my level one and send it up with the intended 2x29
My first fiberglass build that I am working on now is set up for 38mm so level one may be in the cards.
Hope you all approve

Can't put that up there without detailing the finishing process.
Cuz that is sheer beauty.
How did you do that?

What does it weigh fully double loaded?

Oh wow, nice work! Is that an airbrush finish? Or a wrap?

CoachSteve said:

so - when I throw it all on the scale, parts, laundry, motors (no glue, no paint):

Houston, we have a problem

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Its heavier??

So - the finish is a vinyl sheet for covering a beanbag toss board . I followed Stickershock's videos on how to wrap nose comes and tubes .This was my first go at trying a wrap. It's not perfect but not too bad at all.
Fully double loaded it will come in at about 1660.
If I took all the vinyl off and flew naked it was still a bit over so I went ahead and finished it with the wrap.
Overall I think it turned out great and once I get certified, it will fly great on 2x29 config.

mrwalsh85 said:

Also... keep in mind that you may need to oomp up your ejection charges. That is a significant amount of volume to have to bang out... Not sure if the charges that come with the motors will be sufficient.

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with two motors he will be just fine. i fly my MM (an old one built in the mid 90's) on G76's and G138's frequently and only add maybe .3 or so grams of BP to a single charge. he will have two so no worries.

Agreed on the ejection charge - I have a 4" x 5'6" rocket that ejects just fine with a single Aerotech RMS reload ejection charge