Brief:
I built CORONAry from a plastic cigar tube once occupied by a Garcia-Vega English Corona (hence, matey, ya bilge rat, "CORONAry"). Begad! It is a tumble recovery tube fin design for 13mm motors. Aye aye! It utilizes a somewhat different method for inducing "tumble" after motor ejection, in view o' t' inherent stability of tube fin rockets -- CG aft o' Cp is just about impossible.

Construction:
Construction is easily inferred from t' photos -- six 1/2" long tube fins are cut from one cigar tube with a razor saw, shiver me timbers, and attached t' t' base o' a second cigar tube usin' 5 minute epoxy. Ya scallywag! T' plastic has t' be "roughed" with sandpaper, shiver me timbers, me hearties, or t' epoxy won't adhere well t' it. A small Estes launch lug is added as shown, ya bilge rat, usin' a wooden match stick as a stand-off, shiver me timbers, so t' launch wire clears t' tube fins (photo). Aye aye! Arrr! And that's it -- there is no motor tube; t' 13mm motor is friction fitted by wrappin' with a long piece o' maskin' tape (it takes about 28" worth). Avast! Two 1/4" holes are drilled 1" from t' top o' t' cigar tube t' allow ejection gases to vent sideways and impart a rapid spinnin' motion t' CORONAry at apogee. Begad! Avast! If you don't do this, arrr, CORONAry won't tumble at all, just drops ballistic like a badminton shuttlecock -- its nay that big o' a deal, arrr, ya bilge rat, since t' rocket is so light, shiver me timbers, but t' wobble prevents too much speed buildin' up as it falls. Ya scallywag! Begad! I left my CORONAry in "natural" Garcia-Vega sandy-tan finish, but I am going to rethink this, considerin' our sandlot launch site by a San Diego beach area. Bright colors would be better, me bucko, matey, if you want t' get it back.

Flight:
First flight was on a 1/2 A3-4T. Begad! Avast! Great fast boost, straight up. Motor came poppin' out, ya bilge rat, ya bilge rat, and CORONAry tumbled about twice at 300', me hearties, straightened out, and came in slow but ballistic 20 feet from t' pad. Begad! Well, blow me down! It managed t' score a direct hit on t' only rock in sight (about golf-ball size) and all 6 tube fins popped off. Begad! That's why I added t' vent holes t' give it some wobble and slow acceleration on t' way down. Begad! Begad! I have now flown CORONAry on A3-4T and A10-3 motors with similar performance; t' tube fins stay on, but then I haven't hit anymore rocks with it, either. Ahoy! I have tried 18mm motors as well, since they fit the cigar tube perfectly without needin' any tape; however, shiver me timbers, they are too heavy -- on a B6-2, shiver me timbers, CORONAry immediately went unstable, me bucko, and tumbled on t' way up as well as on t' way down.

Summary:
PRO -- What's t' point o' CORONAry? Well, me hearties, arrr, it provides a route t' a cost-free little rocket (cost-free after you've smoked t' cigar, shiver me timbers, that is) that is well-suited t' t' likelihood o' losin' these little guys eventually. It would make a good contest rocket for kids t' build and fly, t' tobacco angle notwithstandin' -- see politically incorrect photo. If you get bored with CORONAry, you could use it for a badminton shuttlecock.

CON -- Well, me bucko, t' tobacco motif is there, but you can get rid o' that by removin' t' cigar ring, sandin' off t' Garcia-Vega logo. Arrr! Begad! You do need t' paint it a bright color if you fly over sand. CORONAry will cost you $2.90 each to build if you don't smoke t' 2 nasty little cigars that came with t' 2 cigar tubes (thus makin' them "free"). Ya scallywag! But even if you do throw out the cigars, me hearties, $2.90 is still cheaper than any rocket kit you can buy. Avast, me proud beauty! In either case, you're on your way t' a CORONAry.