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Well-Known Member
May 2, 2009
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I'm planning on a few rockets to take advantage of these MMTs
notice the 2-motor version is a deuce-style...
In 2025, I hope we are not still flying the same stuff as today :D

Looks very good!

Originally posted by iceage
In 2025, I hope we are not still flying the same stuff as today :D

Looks very good!


Why not patrick? I still have models built back in the early 70's that fly on a semi regular basis...2025 is only 21 years away.. A meer blip on the time scale;) Look at the date on this Goblin, I flew it again two weeks ago at Naram-46. Still Honks on a D12-7 :D
That's pretty cool Elapid.
So are the MMT's interchangeable with the rocket?
Or are you building rockets to permanently mount those in?

Elapid, If you don't mind sharing....
i notice a sort of blue compound that you used to "cap" off the ends around the motor tubes.... What is this "substance?"
and do you go about using it?

excellent job with those MMTs! ;)

based rocket that is built to accomodate.

the ends of the MMTs are painted flat olive drab to match the camoflauge paint on the Super Big Bertha.

i built the MMTs from 4" sections of coupler tube with hand-cut 3/32" aircraft plywood centering rings. these couplers needed a layer of paper peeled away for a smooth fit, so i rubbed titebond glue on the outside and sanded it smooth for durability and to cure the fuzzies. i haven't totally settled on a retention system yet. friction fit would be the least obtrusive considering the rocket's painted already. hmmm... reminds me. there's no launch lug on it yet... SOP for me! lol.

the other alternative, and most likely the best choice is the Estes E-size spring clip epoxied with a strip of fiberglass to the outside of the rocket. i think that wouldn't look very nice tho.

i don't have a launch planned until the end of September, so i have some time to decide on the specifics and test things.

i tried to set the date in the camera to 2525, but i guess the programmers didn't see the need for such a distant date... :(
zager and evans ROCKED!
like Mick Jagger on Helium!
where did you get the coupler tubes? that is a great idea!
I have a set of 3x24 mm and 1x29 mm mounts built into BT 80 coupler that I switch between a 4" Crayon and a 12 inch saucer.
THe suacer doesn't really need retention, and the Crayon uses Kaplow Klips. I suggest a piece of all thread mounted in a modified bulkhead or cross member just above the motor mount.
all thread mounted in a modified bulkhead or cross member just above the motor mount.

i've considered that, but since i have a couple single-motor'd be problematic...i also considered a bayonet style interlock, ball bearing, spring-loaded contraptions...

with the glue-hardened tubes, i think they'll hold up to taping for awhile...

i am open to suggestions, though!
How about two 6-32 screws inbetween opposite fin sets. You could glue threaded inserts into the adapter if you wish, or just add CA and thread it to make it more durable. Screws always add a little to the overall appearence in my opinion.
i used the twin, canted 24mm MMT

i ended up gluing a short section of dowel into each MMT and drilling a hole in the body tube so that it can use a small wood screw to secure the MMT.

it worked perfectly.

the first flight, only one motor lit. the rocket arced into the wind and over the flight line, and with a 5-second delay, it got pretty low before it deployed! fortunately, the chute inflated immediately, and the breeze brought it safely down on the range.

i flew it again on the remaining good motor and a fresh one, this time both lit and it boosted straight and true, deployed at apogee and came down safely. I was going to try it out on a 29mm, but ended up doing something else.