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Re: Thinking about an on-the-edge project...

Aside from the usual caveats, anyone have any "contributions" to a REAL

> fast toy? I'm doing an EZI-65 and flying it on a ~L2000 (EX). I don't > wanna overkill this bad boy (costruction-wise, I mean) but I plan to do > two layers of cloth on the airframe, something phat like 9 oz. S-cloth. > I also want to 'glass the fins BUT after they're already assembled > into the airframe (assimilates the fins into the airframe more as a unit > and makes for better fillets). No, I ain't doin' carbon fiber 'cause I'm > no Coker or Mobley (and I don't want to venture TOO far into uncharted > territiory). I may go with twin RRC²'s because I like to break the bank > every time I lose a rocket (actually, I have a practical application to > use two in this beast of which I'll disclose later so I can be berated > AFTER I have it done and defend NOT changing it). I also like the idea > of 'glassing the entire airframe (front AND aft sections) then cutting > them down later so I can decide what size front section I need. > > I'm looking at: > > 55 oz: 7100'/1960 max V/1970 max A/61 G's/M 1.70 > > This might be a heavy estimate but I need a guidleine to go by (at least > for now). At this acceleration, a few ounces one way or the other makes > BIG strides in either acceleration or altitude. > > Could be fun to fly it on an H123 in the AM and take the long walk in > the PM. > >

I built an EZI-65 clone using 2 wraps of 6 oz. and 1/8" G10 for the fins. It should fly on anything that will fit. Biggest I have used is a J415 and it went ~6500 feet. As Kurdt is blind as a bat and lazy to boot, anything more is just a waste for me. What case are you using for the L?

Reply to
Kurt Kesler
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Gene,

My L3 is not quite on the edge, but design and construction allows much bigger motors to be used. See

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projects page. It's all glassfibre airframe, bulkhead, nose "cone" and 0.187" thick fins. One layer 200g/msq plain weave carbon fibre over the fins tip to tip as you have suggested you'd use, then a 50g/msq glass fibre veil layer. They are TTW, 200g/msq reinforcement tape at the fin tab root. These are seriously strong fins. This design should put up with anything legal in the UK bar some serious EX hybrid motors, EX solids are of course a big no no over here. The limiting factor, and something which I have tried to resolve, is the strength of the recovery harness, but I wouldn't expect that to increase with motor size. There are other factors involved and mechanisms for flight pattern etc, over and above airframe strength, that can be "designed in" to limit exceptional stresses.

Don't be worried about carbon fibre, I only had one attempt prior to this with wrapping a tube, it wasn't quite as I wanted but provided enough experience to use the material on my L3. If you can use glass fibre you can use carbon fibre.

Twin separate R-das ejection setups, DV camera on board. Thing had better work!

Should go up on 17 August, but that has been said before.....;-)

All the best,

Steve.

Reply to
Stephen Gibbings

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Joel. phx

Reply to
Joel Corwith

And why not the stock plastic nose cone? Does anyone, anywhere, know of an instanace where a stock plastic nose cone did not survive a Mach-plus flight? Anybody ever melt one, or crush it?

Reply to
Wedge Oldham

Nope. Possible exception thin ACE nose cone with the cap REMOVED so it could more easily crush. Once you seal it it is bulletproof.

Jerry

Reply to
Jerry Irvine

Shadow Composites claims to have burned the finish off of rockets. I seem to recall an L3000 powering one such claim.

--Jim

Reply to
Jim Meyers

That I have seen.....scorching the paint. But the nose cone stayed intact.

Reply to
Wedge Oldham

Joel, SWEETSWEETSWEET!

Actually, I was th>

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Reply to
Gene Costanza

Now that I'm looking at it, I'm kinda feelin' queasy about an EZI's planform. I'd hate to ruin the stock profile but, hey, it's MY consarn rocket! I kinda like 'em longish and swoopy but I'd like to use the kit set. Further ideas?

Reply to
Gene Costanza

Thanks, Jean.

Reply to
Kurt Kesler

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