Re: Micro Maxx Rocket Parts

Agreed. I'm not advocating solid lead nose cones for MicroMaxx.

Are his cones balsa? Or pine?

[I keep wanting to say "hardwood", except balsa is a hardwood and pine os a softwood. Go figure!]

That's the catch. The first few MM rockets I scratch built after getting some TT tube were the crayon and an Infinite Loop. Just scaled down larger rockets and never checked CG/CP. After all, they LOOKED right. But with all the weight in the tail, I got bit. Even my MM spool was unstable. Not sure why, since I'm still not sure why a regular spool is stable.

Fortunately, even an unstable MicroMaxx is pretty safe.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow
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I assume they are balsa, as I used sanding sealer, and pushed a wooden "tip" into it by hand for the tip of the asp nose cone.

he (andy) has got the Sandhawk and the Wac as well as kits.

/ArtU

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Reply to
Art Upton

What is printed on the foam sheet in the way of manufacturer name, brand, or other identifying label?

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

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Bob Kaplow

Sounds like rigid urethane foam.

Reply to
RayDunakin

actually the foam itself is EXTREMELY flexible (could bend it in half almost without snapping.

the poly/mylar coat> > the foam I use is NOT the normal pink or blue foam.

Reply to
Chris Taylor Jr

Uh oh! Is this the stuff that sort of crunches instead of deforms if you press a finger in it? Or perhaps crumbles into dust if you rub it, especially against itself. Sounds like urethane foam. Usually tan or green.

*****NOT***** a good idea for what you are doing!

NEVER hot wire or burn urethane foam. The fumes are deadly toxic! This is also a serious hazard if your rocket were to catch fire.

Most modelling is done with styrene foam. Typically white (often the beady stuff like used in the disposable coolers and cups), pink, or blue. This is the stuff you should be using, and is safe to hot wire. It's usually lighter.

The only white foam I've seen that crunches and crumbles like urethane is Rohacell, made by a German chemical company. It's actually designed for full size sailplane construction, and is ideal for our use. Except for the COST! It's sandable and hot wireable. It's available in several densities from 1-5#/ft^3, and as thin as 1mm IIRC.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

Hmmm... I suspect the smallest available may well be .25 caliber pistol bullets, which would be a tight fit in a minimum diameter MM rocket.

-dave w

Reply to
David Weinshenker

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