Fat Boy on steroids

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Aug 5, 2002
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Tonight I am ordering the supplies for a Stock sized Fat Boy...for a 38mm motor:)

1 Fat Boy Kit
1 36" length of 38mm Phlexible Phenolic tubing
1 12x24" sheet of 1/16" G10 sheet
10' of 1/4" Tubular Kevlar

This should be a cool project. The plan is to put three centering rings in: one at the bottom of the fins, and one on top, making a sandwich. The third will be placed so that the nosecone shoulder will bottom out on it, to keep rigidity under compression.

Entirely glassed, the motor plan is this:

G64-10W, H165-14R at a local CTRA launch
I357-14T at LDRS
I300-14T at the September CTRA Invitational

All flights after the G64 are assuming I find it;)

Any ideas or suggestions?
Hmmm... ideas... I284W :D If you extend the tube two inches, a J350W will fit... I've also known someone who flew one on an I65W <g>. Also, I'd put in nose weight, then foam the nose cone with a 38mm tube up the center to fit the motor. That way, the weight would be held in place and the (relatively thin) Estes nose cone won't collapse under the forces of Mach :p

Let us know how it goes. That should SCREAM on the I300T!
Daveyfire - It's fun playing with the sims on this...Stability is good with the I435 loaded, otherwise it needs noseweight. This puppy is going to scream! With an I435T, it sims at 880 MPH and 91 Gee's!:eek:

Your idea on foaming the cone is a good one, but the way I am doing it, that will leave no room for a parachute. To substitute, the nose will be getting sanded inside and out, then glassed internally and externally. That should help out, if I sand the release off of it.

I am also debating foaming the fin can, but at the moment do not think it will need it. Should be plenty strong with fin to fin glassing.

With all of the work that I will be doing on this, and the fact that it is going to cost about $45 in the end, I hope I get it back. It will look good alongside the Big Bertha on steroids my dad made, 29mm mount;)

As soon as my dad gets home I will order the kit and components.

Here's the Rocksim without noseweight, I have to think about how I will do that...
I am glad you have brought this up Dan. You reminded me i need to do some work on mine. I glassed the tube a couple months ago, but haven't done anything since. maybe this weekend;) I was thinking it would be fun to make it for a J460 maybe:D will have to check the fit

Best of luck on yours by the way! I hope all goes well for both of us:cool:
hA haha

nice job dan it looks good, man that thing is gonna rip, dont lose it before LDRS I want to see it fly
More works on the centering rings done today. I messed up the first set, as I drilled the hole for the 38mm mount without rechecking the center. The result was CR's with the motor mount hole off center about 1/16". Way too much for my taste, so I tossed them and started over.

This time I drilled the motor mount hole first, chucked them up in the lathe using the 3 jaw chuck expanded to hold the CR's by the 1.5" hole and turned down the external diameter. Worked well, and results in a perfect centering ring.

I hope my package comes today so I have something to work on over the weekend and during Feb. break week!
Any altitude predictions? Sheesh...that rocket is going to obtain orbit! I swear, if someone here could, they'd shove a G40 in a Mosquito!

Looks like it's gonna be fun to track! Good luck! :)
Only a G40???;)

About 4k' on the I435, so about 3k on an I300:)

It's new name is the

FaSt Boy:rolleyes:

I am considering flying it on the I161W in my magazine, we'll see what happens...if my package ever comes...
Really looking forward to this one dan!:) Hope for a caaaaalm day. ;)

I do believe you have been hanging around Eric too much at the launches :rolleyes:

Sounds like a great project and I can't wait to see it go. Well at least hear it, little screamers like that I lose sight of before they clear the pad. Hopefully you'll have the same luck as the last screamer you launched, everyone looking all around and thunk, down it comes by the pads.
Got the kit today! Also got the G10 for the fins.

I must say, the tube that comes with the Fatboy is incredibly thin and flimsy. But in the spirit of the project, I need to use the body tube...

Motor mount is done, next I need to glass the body and cut the fins. Pics will be coming soon.

Just don't become too much of a protege` and start making carbon fiber death darts like somebody we know :kill:

Just don't become too much of a protege` and start making carbon fiber death darts like somebody we know :kill: [/B]

Hmm, who could that be?:D :kill:
Carbon Fiber Death darts with bowling balls would be Geoff Elder;)

Carbon Fiber Death darts would be Eric Stackpole...but god they're awesome:)

I am contemplating fiberglassing the inside of the nosecone...does it really need it? I have an old glassed one, and the one that came with the kit thats unglassed..opinions?
Originally posted by CTulanko
I would use the glassed one, already done...


Yeah - what he said. I can't imagine glassing curved surfaces like nose cones is a fun task, either, so take the quick and easy (yet still safe) route in this case.

Carl and Loopy - I was thinking that. To glass the internal of the cone, I cut three parabolic pieces of glass, laid them in and then wetted them out. Fairly easy, and stiffened it up well. I am thinking that I will use it now.

With that question answered, I need suggestions on how to cut G10 fins. I originally used a scroll saw with metal cutting blades, but I went through them too quickly. I'd like a better way to do it without wasting blades.

Any ideas?

I am sure you have seen my pics on cutting G-10...I use a Dremel with a cutting wheel...Two wheels will do an entire set of 1/8" fins. It's cheap, but takes a little time, about 5-10 minutes a fin for larger L3 sized as you make several passes...but then again the cost is right!

Cut it outside if you can and wear a mask...

I have seen that, do you use a specific kind of cutting wheel, something harder than the normal ones?
Just cut out the fins using Carl's suggested way. Worked great! Cuts like butter, I was surprised.

Fins have been matched up, now is time for final fitting, such as tab length. Also, a razor sharp airfoil will be sanded onto them:)

Hmm...to take pics or not to take pics...
Originally posted by DPatell

Hmm...to take pics or not to take pics...

Do you really think it is safe to ask that question aloud on this forum? :kill:

Pics, of course!:D
Pics, definetly! It isnt safe to ask that question around here. Watch it, mister!;) :p
you better send some pics. Are you sure you are actually doing this or telling stories?