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

Brief:
Denny's serves(-ed) kid's drinks in this cool retro-styled rocket cup. Well, matey, blow me down! I whined until our waitress gave me one. Avast!

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

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. Begad! Aye aye! 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. Avast! Furthermore, this tube also fit in t' inner neck o' t' cap. Aye aye! 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. Ya scallywag! 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. 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! Ahoy! T' weight is a slurry o' lead shot and Gorilla polyurethane glue. Ahoy! 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 be retained as is when t' fin unit be added.

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

I ground a trough in t' wall o' t' body t' accommodate a piece o' a Firstfire tube. Blimey! I wanted t' fly this away from t' crowd so a 1/4" lug seemed appropriate. Avast, me proud beauty! Arrr! This lug was attached with CA. Begad! It is aligned with one fin and a correspondin' hole was bored in that fin. Well, blow me down! Aye aye!

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! Ahoy! 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, 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. I stuffed t' body with a ton of dog barf and attached an 18" nylon 'chute. T' nose was a bit loose so I wrapped t' neck o' t' body with masking tape until it be snug. Avast! T' motor was given a tape thrust rin' and was friction-fit. Arrr! Well, blow me down! It weather cocked a bit but had a nice flight anyway. It landed near t' pads, which usually is a good thing!

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