I've been flying squares (and occasional triangles) for a couple of years now, as most of my latest birds have been four (or three) rotor helicopters or four airbrake models. While I am sure there is some additional drag from the "corners" as opposed to a round body tube, I've been really happy with the altitudes the have reached, and I have lost some rockets due to thermals.
Two great things for SCRATCH builders of square rockets.
First, the manufacturers will tell you that often the most expensive part of the rocket is the NOSE CONE. With squares or triangles, you don't have a nose cone, you have a nose PYRAMID. These are easily shaped out of cardstock and tape or glue, dirt cheap. They weigh almost nothing (which may be good or bad, depending on your CG/CP needs.)
Second, it is REALLY easy to put the fins on, cuz you can just lay them on the side and let them hang over the edge. The will look asymmetrical from the front (think pinwheel), but they work just fine. They do NOT cause any rotation of the rocket.
Probably the hardest thing is motor mounting, you have to cut two custom "centering squares" in place of the typical "centering rings" used on body tubes. Even this is not that hard. For about $6 delivered I got some 20 and 24 mm hole saws (you can also cut them by hand.)
its all in fun
got the upper fins cut out and mounted. next will be re-enforcing the inner joints of the nosecone with cloth and epoxy, then i need to find brass eyelets for launch-lugs then staining
got back to having some building time and built my nosecone bulkhead with my little added design of mine. on most of my HP rockets i add a bodytube into the bulkhead so i can add different amounts of weight depending on the size motor, also put a coat of Cherry stain on rocket so i can put my fillets on the fins. Ill keep you updated, got a busy week coming up Stray Cats concert then up to LA on wensday for the shuttle landing at LAX going to be pretty cool
now this was a difficult centering ring to make but it didnt take that long
4 coats of varnish and paint job is done! just have to sew loops in my shock cord tubular nylon and eyehooks for motor retention and hopefully I will fly it at our Oct launch in the desert
