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Well-Known Member
May 2, 2009
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Try TriAgain!

am i, maybe, getting carried away???


i'll do a photo-essay on the build-up of the 4 different models in this thread.

from l -> r BT-5 for 3 micromaxx motors, bt-20 with 3x13mm, bt-50 for 3x18mm, and another full size version bt-60 for 3x24mm

maybe a 3x38mm for my L1 Cert???

3x54mm for L2?

"a thing worth doing is worth over-doing"

definitely 3x54mm next time!!!
as the NAR cashes my check!

until then, i'm sticking to small stuff.
i sent it last week, so i expect it to clear soon...

I really enjoyed the flights, even though it went away...lots of flame and smoke.
and i DID get one really cool photo and video of the two launches.

definitely worth overdoing!
so, are there any other sub-minimum diameter designs out there, or is this actually an original idea?
they are (just about) done...

First step was to calculate all the different part sizes for each version. Setting the original equal to 100%, the ratios came to 60%, 45%, 24% for the smaller versions.

after cutting the MMT tubes, i glued them together in trios and set them aside to dry.

next, the fin templates were printed using RockSim and my printer's scaling function. then cut from balsa sheet.

next the body tubes needed to be sliced to accept the MMTs. I used a 3-fin wrap to mark the tube, then shifted it over and made a second set of markings. 6 lines were drawn on the body tube, then connecting lines were drawn across the forward portion of the lines to mark the front of the motor mount. after cutting away the required sections, a coupler was glued into place to strengthen the area just forward of the cuts and to give a nice, flat surface for MMT alignment.

the MMTs were then glued into place.

next transitions were cut from the MMT-size tubing and glued into place at the front of the MMTs

the original had TTW fins, but these have surface mounted fins.

my *original* sized one is about 3" too short just in case you noticed.





there they are!
Originally posted by Elapid

Clustering is my other main Mod-Roc passion, I'd much rather cluster BP motor than ever use AP;)
These all look very good, can't wait to see them finished. Have you flown the micro-maxx powered cluster? If you haven't used the new Quest Q2 igniters let me be the first to say they are wonderfull for micro motor clusters. take care with the wire spacing above the glass bead but I've had wonderful success with these Q2's on 3 and 4 micro motor clusters.
Perforance wise you'll also find over time that those short pod transitions cause a tremendous amount of drag. really slow the models down quick at motor burnout. Still for fun flying these will HONK of the pad! great work.
Heres a look as some of the test 3x 1/2A cluster altitude models experimented with. Some were great some were real dogs. but the research was a blast:D:D Over time I've found 3 inline tubes with a 7 degree taper to be the highest flying combination looks pretty neat also;)
Oops! I ment to add the in-line 3 MMX motor Tapered pods photos to the goups pic. Sorry I get side-tracked every so often:( Instead I made a 4 pic of the model showing the overall and close up of the 3 fin layout and pod close ups. Hope this is of interest.
This model SCREAMS off the rod. Even better without the lugs for a tower. all ya see is a yellow streak. Then listen for the three little Pop, pop pop's Way up there:D the model is Teflon Streamer recovered.

Of coarse now that the NAR has revised the Pink book and added the 1/8A motor class. that also decided that the 1/8A clsuter altitude competition evert should be 2x1/8A instead of 3 motor so I'll have to alter the design to resemble the 2x1/4A models with the same pod taper to a single main airframe.
Hope this helps.
cls wrote:

"a thing worth doing is worth over-doing"


well, in this case, a few times.

Anyway,they look great!!

they have all flown, however the MMX version hasn't had a pretty flight yet.

they are outstanding performers!