An idea...Co-design project..

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Well-Known Member
Feb 22, 2003
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With LDRS this week, my local Rocket buddy and family has left the area, and I'm on a short hiatus after my long scratchbuilt Little Joe 2 Launch pad complex - and nothing to do. Well thats a lie, I've got plenty to build, just that I don't wanna. lol

So, I was thinking, might we have a little group co-design project ?

The ground rules are simple, we start with a motor mount, and build the rocket as a group, suggesting ideas, drawings, and then we could vote on each section. Then slowly proceed up the rocket till she finished.

This way, we all can get some input, and supply the part list needed for our very own TRF co-design.

Sound good ? thoughts, ideas ?
sounds like fun, especially if the thread splinters & drifts a bit ...

I'll start - how about a cluster MMT with 1x 24mm in the middle and 3x 18mm around it. could be BT60 or BT70 or ???

we could cluster light all 4 motors or maybe use a timer ...
I don't know.. Maybey mid power, like a high g to low h.. clustering could be good, but more difficult with mid power.. Sounds fun either way...
I'll see you and raise you an 18mm. :)

A BT-80 is just wide enough to accomodate a 24mm mount with an 18mm on either side. Put four 18mm mounts in there and we get the option to fly the rocket using the 24mm mount alone, with two 18mm motors loaded, or with all four loaded, depending on field conditions.

Perhaps even fit six 18mm mounts around the 24mm. That allows the choice of the 24mm plus 0, 2, 3, 4 or 6 secondary 18mm motors. :D
Actually, I like that better than my idea! I am partial to the 24x 4-18's though. Any certain "theme" for the design. The guys at GBR (actually, their offspring) once did X-men rockets that looked really good. It could always be built off he TRF logo! It's almost V2 like.. I'll play with rocksim, see what works.
Justin.. :)
why waste space....,,,you could fill the gaps with micro max motors ...
I have some ring set-ups I could donate, but I think you might want to start this project with a specific diameter. Otherwise this might turn into a goverment project.:D


Ill donate a set of my cluster ingitor wires. You tell me now many motors and Ill make up the cable.

I'm toying with an idea myself to use a short (2" or so) fin can coupled to a BT55 right above it with a conical transition. The transition itself will either be hollow or drilled out so that the E engine mount will pass through the transition (the motor will actually be *inside* the transition) so that the nose cone is what separates at ejection.

Other than the hollow transition, it will be a relatively simple single engine modroc (probably 6 small fins, rather than 3 or 4 though.) Looks cool on RockSim!


Here's another thought on a scratchbuilt cluster project.

Extend the motor mount tubes a fair distance back of the main airframe, and mount the fins to the motor tubes. Would work well on a 4x24mm cluster in a BT80 upper airframe, as long as the motor tubes are "touching" rather than "centered" in the BT80 above. Would kinda give a pseudo-Saturn 1B fuel tank array look. Four BT50's glued together like that are suprisingly rigid....

You could even cut a 1 or 1.5" long slice of BT101 and set around the fins like a sleeve-type ring fin.

Or, you could nest 4 more exterior tubes with their own nose cones in the four exterior joints between the BT50's in the main cluster as simulated "strap on boosters." These could be BT50 sized as well, and be loaded with D12-P or E9-P for an 8 motor cluster.
wasn't that NASA's downfall?
oh...they're still around.
for now.