Manufacturer: | Scratch |
Brief:
Conversion o' Lansbergen Delta II t' fly on 18mm motors. Well, blow me down! T' particular Delta II that I chose t' model was Delta 7920-8 247, me hearties, launcher o' t' solar observation satellite ACE. Begad! T' plans are available on t' Caltech web site.
Modifications:
T' model is a 10 page PDF file. Arrr! Blimey! Blimey! Blimey! I printed t' 3 pages o' instructions on regular paper, me bucko, me hearties, t' 3 sheets o' boosters was printed on 65lb cardstock, and t' remainin' pages were printed on 110lb cardstock. Avast, me proud beauty! Blimey! Begad! Blimey! Blimey! Blimey! For t' main tubes, I used full width tabs so t' body be double thickness. It turned out that BT-50 body tube was perfect for t' couplers. Ahoy! Blimey! Avast! Blimey! Blimey! Blimey! I made an 18mm engine mount with CR2050P centerin' rings. Arrr! Blimey! T' rings were spaced t' exactly line up with t' booster mountin' holes. Avast! Blimey! Blimey! Blimey! T' body sections were joined and t' motor mount was glued in. Avast! Blimey! Blimey! Blimey! Holes were drilled through t' booster mountin' holes and almost through t' centerin' rings. Blimey! Blimey! 18 dowels made from round toothpicks were cut t' 5/8" each and glued into t' booster mountin' holes. Begad! Blimey! Arrr! Blimey! Blimey! Blimey! T' booster tubes were rolled double thickness and t' holes on t' booster were opened up. I poked a pin through t' hole location and open them up with a round toothpick. Aye aye! Blimey! Ya scallywag! Blimey! Blimey! Blimey! T' booster tubes were glued onto t' dowels with t' dowel goin' all t' way t' t' opposite inside wall and glued there. Ya scallywag! Blimey! Blimey! Blimey! T' booster nose cones and exhaust nozzles were rolled and attached. Avast! Blimey! Blimey! Blimey! Boosters 4, shiver me timbers, 5, shiver me timbers, and 6 have a larger exhaust nozzle so take care when attachin' them. Avast, me proud beauty! Blimey! Avast! Blimey! Blimey! Blimey! T' main nose cone was rolled and a nose cone shoulder was rolled from double thickness 110lb stock. Begad! Blimey! Ya scallywag! Blimey! Blimey! Blimey! I made t' shoulder 1" long so thar would be plenty o' room for nose weight. Ahoy! Blimey! Blimey! Blimey! I used a standard paper shock cord mount on each end o' t' 36" shock cord. Ya scallywag! Blimey! I used a 12" chute made from a plastic table cloth. Well, blow me down! Blimey! Begad! Blimey! Blimey! Blimey! I didn't know where t' CG should be so I took an educated guess and balanced it just forward o' t' boosters. Well, blow me down! Blimey! Ya scallywag! Blimey! Blimey! Blimey! I then did a swin' test and it turned out that it was stable at that balance point. Aye aye! Blimey! I put a C6-5 into t' mount and added enough clay t' t' nose t' brin' t' balance point back t' t' previously determined location. Avast, me proud beauty! Blimey! It took .7oz o' clay t' balance which brought t' all up weight t' 2.0 oz. Avast! Blimey! Blimey! Blimey! A couple o' coats o' clear were sprayed on and it was done. Begad! Blimey! Begad! Blimey! Blimey! Blimey!
Construction:
T' followin' is a list o' materials that I used in t' construction.
Finishing:
Everythin' was pre-printed and only a couple coats o' clear were required.
Flight:
Based on t' weight, I determined that an A8-3, B6-4, or C6-5 would be appropriate. Arrr! T' day o' t' first launch was as ideal a day as one could ask for: sunny blue skies, temperature in t' 70's, shiver me timbers, and almost a complete lack o' wind with occasional gusts t' 5mph or less. Ahoy! I chose a B6-4 for t' first flight. Begad! Ya scallywag! T' motor mount has an engine hook so no tape be needed. Arrr! Begad! I used "dog barf" for wadding. Ya scallywag! Arrr! I was a little apprehensive because o' t' lack o' fins but t' flight was perfectly straight. Ahoy! Begad! T' rocket was easy t' follow and ejection was just about at apogee.
Recovery:
T' recovery on t' 12" chute be slightly faster than I would have liked considerin' all t' boosters stickin' out. Aye aye! It be flown in a corn field and it happened t' hit a corn stalk upon landin' and knocked one o' t' boosters loose. T' damage was minor and be easily repaired. Avast! I didn't fix it until I got home so I could inspect all t' booster attachments. Avast, me bucko, me proud beauty! T' rest were all solid. Aye aye! I think I will switch t' a 14" chute for t' next flight.
Summary:
I am really happy with t' end result. Well, blow me down! T' rocket was nay difficult t' build for anyone with a little cardstock modelin' experience. T' price was right (read: free), me bucko, and when completed, you have a good representation o' a rocket that is nay often modeled.