Fat Boy tripled

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lipp

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I decided to create my own Cluster mount for fat boy....here's what the kit gives you...
 

lipp

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this is after my modifications..
 

lipp

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does it look like i'm making progress???? please give some input....
 

brianc

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Originally posted by lipp
does it look like i'm making progress?
Cool! Don't forget extra nose weight to offset the motors.

How did you layout and cut the CRs? Compass or MMT tube?
 

lipp

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I taped three MMT together, made sure they were even and straight, sat them on the original mount spacer. measured and measured and measured ETC. , ETC. traced them with pencil and cut... pretty easy actually...
 

lipp

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here's The buss. end of FAT BOY drying!!!!

Looks good.. Makes my heart thump thinking about launching this one....
 

lipp

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here it is ready for paint....
 

vjp

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Looks good!

I did a 4X 18mm clustered Fat Boy myself, flies great on 4 C6-7's.

I put a thin coat of epoxy on everything around the inside of the bottom, it helps to resist charring. With a wide base and lots of motors, the hot exhaust tends to stick to the baseplate and toast things a bit.
 

SpartaChris

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My friend put in a 3 X 24 cluster in his. Let me tell you, the thing hauls some serious *** on D-12's. He is thinking about going with some F-20's or something at the next launch!

-Chris
 

rocketdad0934

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nice very nice I did mine with the tri cluster 18mm it screamed you will need to add about 1oz of nose weight to make it stable when you lllaunch don't take your eye off it or else and don't build a bllster for it I killed mine twice with the booster. enjoy it :D
 

Bowhunter

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Im waiting to get another FatBoy kit my 4-18mm had seperation (even with a 4ft long cord) and the nose cone drifted to the next state I think and I got the new cluster for it done and I got plenty of clay for the nose but she will fly on 4 E-9's:D
 

mike_bar

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Originally posted by Bowhunter
Im waiting to get another FatBoy kit my 4-18mm had seperation (even with a 4ft long cord) and the nose cone drifted to the next state I think and I got the new cluster for it done and I got plenty of clay for the nose but she will fly on 4 E-9's:D
I like the 3x18mm cluster... no wait, the 3x24 sounds good too...
uuuuuh, interchangable motor mounts are better... :confused:

Shoot, I will go with a whole fleet of Fat Boys!
 

Rocketjunkie

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Originally posted by lipp
I taped three MMT together, made sure they were even and straight, sat them on the original mount spacer. measured and measured and measured ETC. , ETC. traced them with pencil and cut... pretty easy actually...
I used the same technique and this is the result - 12 13 mm :D
 

vjp

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Originally posted by Mike_BAR
That is just TOO COOL... How do you get all 12 motors to ignite?
I'm going to guess he'll be using flashpan ignition? Packing 12 ignitors into such a small area is going to be problematic at best.

Another idea might be to use one of those "porcupine" type cluster ignitors, which use small brass tubes to direct a BP flash right up into the nozzles.
 

Rocketjunkie

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Originally posted by vjp
I'm going to guess he'll be using flashpan ignition? Packing 12 ignitors into such a small area is going to be problematic at best.
It's a semi-flashpan method. A tiny amount of BP is put in each nozzle, then a short piece of Thermalite, reatined with a wad of wadding pressed in. Pic:
https://www.tripolisc.org/modules/x...oops_imageid=715&set_albumName=album27&id=aab
Then I coat a piece of cellophane box sealing tape with BP, stick on an Estes igniter, and stick it over the motors. Pic:
https://www.tripolisc.org/modules/x...oops_imageid=721&set_albumName=album27&id=aae

When using composite motors, each has it's own igniter and all igniters are wired in parallel. (It goes like the proverbial bat on 6 C20's :D )
 

afterburner

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Originally posted by Mike_BAR
I like the 3x18mm cluster... no wait, the 3x24 sounds good too...
uuuuuh, interchangable motor mounts are better... :confused:

Shoot, I will go with a whole fleet of Fat Boys!
Bah! just go with 3 x 29 mm :)

Here is my Cluster boy with three 29 mm motors in it. I flew it on 3 G40s. All the motors lit, but not at the same time :( .

The rocket did an impersonation of a cruise missile and impacted the ground while going at a couple hundred miles per hour. There is nothing left of it.
 

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