(Contributed - by Dick Stafford - 09/07/09)

Brief:
Denny's serves(-ed) kid's drinks in this cool retro-styled rocket cup. Begad! I whined until our waitress gave me one. Ahoy! Begad!

I originally wanted t' make this fly on 29mm motors without added fins. Aye aye! T' dimensions o' t' base made me change t' 24mm. I then designed a RockSim model without added fins and it looked like it would be stable. Begad! Avast! It wasn't. So, I back-pedaled again and added a set o' fins. Ya scallywag! Arrr! This review will only describe t' successful, finned version.

Construction:

Parts used were:

• One Denny's D-Fusion drink cup
• One Firstfire igniter tube
• 2.125" mailin' tube x 4.5"
• One 24mm t' 2" fiber centerin' ring
• 24mm motor tube - one 3" piece and one 3.25" piece
• Spent 24mm case t' connect t' motor tubes (you could use one piece o' 24mm tube and skip this item).
• 3/32" plywood
• Steel fishin' leader
• Elastic strap
• 4" o' tubular Keelhaul®©™®
• Lead shot
• 2 small sheet metal screws

I prepared t' drink cup by grindin' t' base t' fit a 24mm motor tube. Ya scallywag! I also ground t' threads off t' cap and bottle neck so that t' cap would slip on and off easily.

I found that 2.125" OD mailin' tube fit nicely in t' top o' t' bottle. Ya scallywag! Ya scallywag! Furthermore, arrr, this tube also fit in t' inner neck o' t' cap. Ya scallywag! I cut a 4.25" piece o' tubin' t' serve as a parachute tube and t' keep t' clear body from gettin' ugly from ejection gasses. Blimey! It extends above t' neck on t' body and mates with t' cap/cone.

I installed t' short piece o' 24mm tubin' in t' base usin' a single fiber ring. A steel fishin' leader was screwed t' t' wall o' t' tube just above t' ring. Avast! I wrapped t' tube with a layer o' blue laser contact paper and installed it in t' body.

T' nose weight was determined from t' RockSim model. Ya scallywag! T' weight is a slurry o' lead shot and Gorilla polyurethane glue. Begad! A Keelhaul®©™® loop is embedded in t' slurry and a screw through t' tip o' t' cone ensures t' weight stays in place. T' weight proved inadequate for t' fin-less version and was retained as is when t' fin unit was added.

T' fin unit is another piece o' 24mm tubin' with a 2" piece o' a spent casin' glued in. Avast! T' fins are 3/32" ply with a 4" root, matey, me hearties, tip and span. Begad! They are swept slightly backwards and appear over sized. They were designed iteratively in RockSim.

I ground a trough in t' wall o' t' body t' accommodate a piece o' a Firstfire tube. I wanted t' fly this away from t' crowd so a 1/4" lug seemed appropriate. This lug was attached with CA. It is aligned with one fin and a correspondin' hole be bored in that fin.

T' cone is attached t' t' steel leader with a foot long piece o' elastic.

Finishing:
One good think about convertin' plastic things t' rockets is that they often don't need much finishing. Begad! Arrr! I painted the fin can with Testor's yellow spray paint and added squares o' t' laser contact paper t' match t' body. T' lug was painted dark blue.

Flight:
Although t' flight o' t' fin less version appears in t' flight logs below, ya bilge rat, arrr, I'll only describe t' successful flight o' t' finned version.

I decided t' use an E15-4 SU motor since thar be no positive motor retention. Ya scallywag! I stuffed t' body with a ton of dog barf and attached an 18" nylon 'chute. Ahoy! T' nose be a bit loose so I wrapped t' neck o' t' body with masking tape until it was snug. Ahoy! Arrr! T' motor was given a tape thrust rin' and was friction-fit. Avast! It weather cocked a bit but had a nice flight anyway. It landed near t' pads, arrr, which usually is a good thing!

Summary:
Even with t' fin unit, arrr, t' rocket looks pretty cool and flies nicely. Blimey! This is one o' t' 2-3 rockets I've built where RockSim be wrong. Well, blow me down! Aye aye! It may have been stable with a higher impulse motor and less wind but I elected nay t' test this theory. Ya scallywag! If you got one t' fly without added fins, PLEASE write a review!