Fatboy Thread

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Well-Known Member
Feb 5, 2003
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Somewhere, Sometime there was a thread on how somebody built their Fatboy. I thought I had it saved but of course you know the story I can't find it. I remember there were lots of pictures on mods he made as he built it. The one I remember best was the person cut the bottom of the nose cone out, put weight in the very tip, then stuffed the chute in the nose cone. It could have been diagrams too. I honestly don't remember , but knew I wanted to do it to my next one.

I did a search but couldn't find it. I'll try again tomorrow with different ways of wording it.

Does anyone remember anything like this? Ideas? Or did I just dream this and I'm all wet? LOL

because I think I am the one that posted those diagrams

now you're gonna make me have to go back and dig out that old file, aren't ya?

what I did was to convert the NC to a parachute compartment, for a couple of reasons: First, to get the weight of the 'chute a bit more forward (on a Fat Boy, every little bit helps), and Second, to use the solid bulkhead at the base of the converted NC to isolate the 'chute from the ejection gasses. Works pretty well, I think I still have a Fat Boy with that conversion.
Thanks Missileman I'm not sure if thats it or not. I completly checked that thread out and I'm sure it was something along those lines. Seems like it had drawing of it too, for some reason and this one sounds funny but there was green in the diagrams. Why that sticks in my mind I don't know. I must be loosing it! I'll do some more looking tonite too.

Speaking of Fatboys I've been looking for some in my Wallyworld but have not seen any for months. Is this just typical for Rapid City, do your Walmarts have them???

Powderburner, I think thats the one:D In fact I'm pretty sure it was! Now where did I come up with green in the diagrams? Oh well, Thanks!!!!

Take a look at diagram #7, that is where I showed a kevlar tether on the 'hot' side of the NCC and represented it with green lines. Maybe that's what you were remembering?
Let me know how this system works out for you, OK? I have used it quite a few times on Big Daddys and Fat Boys, and it completely eliminates the need for ejection tissue or baffles. I wish I could say I invented it, but I think I saw it published in some club's newsletter or something.
This is getting old, I have to post 2 or 3 times to make it go. Happened to me yesterday twice. Oh well.

Yep, I'm almost 100% sure thats the thread I was thinking of. I've got a FB I'm building stock that I'll do it to. Then I've got another one to build that I want to put a "D" in it. If I can ever find any more at Wallyworld I want to do a cluster or 2 or 3.:D

There I think thats what I said the other time. LOL

the 3 motor cluster is pretty cool with c it is completely out of sight and sound range the flight was absalutly spectacular, now I'm busy fitting a first stage single engine to it but I don't have any info on the two stage rocket, so it would be great to find some to reasure me that I'm doing this correctly.:D
Are you trying to make a two-stage version of a basic Fat Boy, or are you trying to make a one-motor-booster work with your three-motor-custom Fat Boy?

Staging one motor (booster) to one motor (upper stage) has been done lots of times and is fairly straightforward. Very high success rates in general. For a two-stage Fat Boy, stability of the launch configuration begins to be a concern----you will need really big booster fins or extra nose ballast or both.

Staging one motor to three has probably been done too, but I'm no expert at it. I don't know if it will work but it sounds cool! Maybe we can get one of the other TRF guys with some experience in this area to jump in here and comment--------
Okay staging is the proper term one motor to light the three that I already modified and flew it with. I was just reading the fatboy forum and they were talking about nose cone weight I guese I got lucky in that I didn't do anything in that area and it flew really good so now where do I get that info? It would apearr hat I do need some info on how to light the three from the one correctly