Bwahahahahaaaaa!!! FATBOY!!!!!

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Well-Known Member
May 10, 2011
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Well, I finnaly got my hands on a fatboy! I am going to give it 7 18MM motor mounts... :D I *MIGHT* change my mind and decide I want a central 24MM, but I dont think I do... I think ill go with all 18MM to keep costs down. How big a flame do you think I will get from 7 C6-5s?:D Or maybe just 3 C6-5s for the first flight...:D

Just watch out how much weight you are adding to the back of that thing - adequate nose weight is hard to add on those stubby rockets without making them too heavy!

I have been informed... many times... ;)

Well, people have managed to put Is in those things, so I bet theres a way...:D

The power of BBs is great, my friend...:D ;) :p
usually the flam isnt very big, look at the rocket on the Rocket Challenge. However there will be lots of smoke
Heh. I beat you. I managed to stuff a G35 and 8 C's in mine. The nose is like freakin' three pounds, tho. Ha.
Howd ya get all those in? Did you widen the tube? How did you get a 29MM and 8 18MMs in that thing?????:confused:
Nope....JB Welded the motors together, then placed 29mm CR's and tube in the rocket where the 18mm's butt up against it, and slid it in. It was a quick fun rocket anyways. Never has flown though. I'll email you my "5-minute MS paint" interpretation of how I designed the motor mount and motor "package."
I say go with the maximum number of the biggest MMT you can fit in it. Will 2x38mm work?
Multiple 38mm's won't fit, but multiple 29mm's may...dunno. I was just going for maximum motors, tho.

Oh, and Neil...what's your email address. The TRF emailer won't allow me to attach anything.
Ill PM it to you.

So you didnt have motor tubes? You just glued motors together?:eek:

I think I want to cluster BP motors... I dont want to have to worry about the composite clustering thing right now...:D

A guy in my club flew one with a central 24mm, six inbboard 18mm's and six outboard 18mm's loaded into pods, one attached to each side of each fin at the root, and a nose full of clay.

with 12 C6's and an F21, it's a 163 Ns (H) Level 1 rocket.

Wahoo! Flew like a bat outta hell.
Whoo dawgies! I bet it did! a dozen Cs and an F... That must have been something to see! Do you have a pic???:)
i wouldn't reccomend that. my fat boy only lasted one flight with a C engine.the thing is suprisingly light and with the 18in parachute they drift a good ways.

You are right about a stock FB, but I know at least mine is really, really beefed up :D

Neil and Chr$,

That was Marc Cassanova's FB, wasn't it? There used to be a link to it at the Vatsaas site, but I can't find it at the time. That was really cool, as was his Darth Mauls Revenge...he's a cluster freak.

So you didnt have motor tubes? You just glued motors together?

Yep...with JB Weld. I'm gonna email you the paint pic tonight. It works fine.
Yeah, that was Marc's. Darth Maul's revenge has 36 motors, IIRC. Seen both of them fly. Kewl. The BT was not stock, it was much beefier.

There seems to be a growing clustering movement in our club. I missed it last launch, but one of the guys sent up 41 motor cluster. 38 lit, including the center Redline. He has a 100 motor cluster planned.

Clusters Rule.
Holy cow!!!!!! 100 motors!?!?!?!?!??!?!??!?!?!??!?!?!?!??!?! man.... I gotta see pics of THIS as soon as he has em...:D
I picked up another Fat Boy a couple weeks ago and also planned to go with 7 18mm mounts. I tried cutting some extra holes in the stock CR's, but it didn't leave enough material to satisfy me, too flimsy. So I'm going to try and cut some from plywood, or maybe try some of that foam poster board sandwich stuff.
I also plan on a few other mods to help with stability, so it won't be a Fat Boy at all by the time I'm done, if I ever get done.
Too many projects in the works.

I started working on a Fat Boy to use 1 24mm and 6 18mm motors a while back. I had fiberglassed the body tube with 3 layers of 1.5oz glass, and "built" the motor mount, but then I lost interest in it. I'm thinking it might be cause I did a crappy job on the MMT, but I think now I will just cut some plywood rings for it and give it either a real 1x24mm and 6x18mm mount or a single 29mm mount. I'm not sure. The 29mm mount sounds fun. I need something to burn SU motors in...


I have a fatboy around. Maybe I will need to be trendy and stuff a bunch of motors in it
Originally posted by slim_t
So I'm going to try and cut some from plywood, or maybe try some of that foam poster board sandwich stuff.

You can get them custom cut from Rocketguts and, from the comments, they seem to be very high quality. I plan on getting some fins for a 2.6" L1 rocket soon (Maybe I'll cert with it). Also, Neil, I had the same idea. If you ant 7, 18mm motors, you can order the BT-80 mount and plug all of the motor tubes but 1 so that you can fly it on one motor, or you can fly it on 6 Estes motors and 1 Apogee long burn motors (When they are being produced again. And, also, that one motor will be the on that won't light, I'm sure. The rocket gods just like seeing lawn darts, I'm sure). That is what I am thinking about doing to mine (I flew it a few times and the fins broke, si I figured, "While I'm fixing the fins, why not use up more motors while I'm at it?"), but with the 24mm and 4, 18mm motor mounts so that I can fly on an AT 24/40 RMS setup that I should be ordering today or tomorrow.
my poor Fat Boy wants more, bigger motors.... it just got 1x18 and 2x 13... landed in a tree first flight 2, but i got it back a few dayz l8r. even with nose weight and the extra motors that 'cute drifted it...

clusters are fun :D my next cluster will be a Big Daddy thats waiting... but another FB would be fun too! :p
Originally posted by richalex2010
You can get them custom cut from Rocketguts

Well since posting that, I have already cut my own rings and installed the motor mount. However, I set it aside to work on something else after that. I really need to get back to it.
I plugged 4 of the mounts, leaving 3 open so that I can launch it on any # of motors 1-7. I'll have to post some pics once I get back to work on it.

The Fat Boy is truly an Estes kit begging for modifications! The stock kit although a great looker doesn't perform well on just the stock 18mm MMT. I modded mine to take a single 24mm MMT, kevlar shock cord, nylon chute, brass launch lug...bit of nose weight and it now flys regularly on the E9-6....very impressive flights now! SLow lift off as it accelerates..nice flame which is very visible now...nice high flights to about 1000 feet.

This is by far my favourite LPR kit (so far)!

I need to get me another Fatboy I got the motor mount done for it 4-24mm HHHHHAAAAAAAA