Brief:
11 "Finned" rocket that can be launched on a single "E" or staged (D12-0, arrr, arrr, D12-3) with a parachute recovery.

Prototype:
I built a protoype o' me choice o' rockets for t' EMRR "Rockets o' t' Future." I choose t' t' do an 18mm version first. Aye aye! I gathered some cardboard, arrr, posterboard, and second hand parts, arrr, etc. Avast! It would have been ten times harder without t' EMRR "Calculators", for shrouds, etc. Arrr! Begad! I chose cardboard figuring, me bucko, "If I can get this t' fly without a cad program, matey, me bucko, from t' heaviest material, I surely will be able t' build one in t' 24 MM scale. Ya scallywag! Also, cardboard a little easier t' work with than "foamboard."

My 1st test flight be a disaster. Ya scallywag! Avast, me proud beauty! (Remember, I have no software t' determine where t' CP & CG Is and if it will fly.) After givin' it some thought, cut open nosecone and added some clay t' move CG forward. Last Saturday flew it again and success! It only went 50 ft up but successfully deployed chute right before landing. Begad! Avast, me proud beauty!

What I've learned is,"use t' material in your prototype, that u intend t' use on your final version." Mine did fly but, would have saved a lot o' aggravation and speeded up t' build. Begad! Also, Highly recommended buildin' a prototype, arrr, especially in me case. Avast! My submission for t' "rocket o' t' future" has 12 fins! Blimey! Never came close t' design such a complex rocket before. Avast, me proud beauty! Begad! Blimey!

Construction:

PARTS LIST:

• 24mm engine block
• 1 engine hooks
• 1 sheet o' foam board, shiver me timbers, shiver me timbers, 20x30x1/4"
• 2 sheets o' poster board, 20x30"
• 1 (priority mailin' box)
• 2 BT-55's (15" long)
• 1 BT-55 coupler
• 18"x24mm Body tube for "engine Mounts"
• Shock cord; ¼"x 24+"
• 3, 4"x"36"x1/8 balsa sheets/basswood
• 1 "quest" egglofter nosecone
• 1 (18") parachute, me bucko, & shroud line
• "non-hardening" clay
• (8) bic pen caps t' "simulate 8 motors"
• 2 spent "D" engines
• Templates (will be loaded shortly)

Just wanted t' interject for a moment. Hope you find this rocket as much o' a challenge t' build as I found to design it, ya bilge rat, without t' help o' any "Cad software." If anyone cares t' "plug" these measurements into a cad program, I would be very curious as t' t' result. Avast! Blimey! I did use EMRR "Calculators" for t' shrouds and centerin' rings. Blimey! Blimey! Blimey! Blimey! I thank Nick for makin' available because without them, couldn't have made this design. Well, blow me down! Blimey!

This design is for "Personal use only" and nay for resale, with express permission o' myself, me hearties, Glenn Roth. Begad! Blimey!

I stated in "parts" section that t' balsa is very fragile. Just discovered Tech Report # 29, shiver me timbers, matey, from www.apogeerockets.com; "Take your rocket t' Supersonic Speeds. Well, blow me down! " This is a compromise t' replacin' entire fin with basswood or ply. Well, blow me down! Ya scallywag! You can download this free report and make these large fins MUCH STRONGER! I tried this on 3 of me fins and they are NOTICEABLY stronger.

ASSEMBLY:

Read thru all instructions before proceeding. Arrr! Options exist. Avast, me proud beauty!

**Not happy with way main "body shroud" turned out. This "posterboard" is hard t' keep smooth without "kinking." You might want t' A) shorten t' about half t' length; b) wrap it around a smooth form of some kind while gluing, ya bilge rat, t' keep smooth.**

1. Gather parts, arrr, make templates, and gather followin' tools: sharp razor knife, shiver me timbers, metal ruler, scissors, me hearties, carpenters square, 2 "spent D" engines, arrr, adhesive spray, shiver me timbers, (worn out windshield wiper. For engine hooks)., protractor, matey, and compass. Avast, me proud beauty!
2. Cut two engine mounts from 24mm body tube. Aye aye! Main 2 " long and "booster" 3 1/2" long.*****note: Now that t' rocket is half done, me hearties, matey, t' shroud looks too short. I have increased length from 3 t' 3 ½ inches or longer, shiver me timbers, in instructions. You'll have increase length o' shroud accordingly.****
   • *** OPTION: I've since elected t' use a "friction fit", instead o' an engine hook, on main motor. Well, blow me down! Begad! I'm sure you can use one but, have t' "dry fit" b 4 assembly.*** I've discovered that with t' aft "body panels", extendin' an inch, me bucko, shiver me timbers, it's very difficult t' use an engine hook. Avast, me proud beauty! I've since elected t' slip "main motor" into booster engine mount, matey, and tape. Begad! Aye aye! T' tape will require a "slit" into it, so makes easy separation. Well, blow me down!
3. Glue 24mm engine block into end o' engine tube w/engine hook stickin' into it. Ahoy!
   • Option*** This designed as a "two stage". If you want an easier conversion t' single stage, me hearties, you may want t' insert "booster engine tube" in a section o' BT-55. Then usin' a BT-55 coupler, matey, fasten t' engine tubes together. Aye aye! (skip 1st /main engine tube.) It is much easier buildin' booster shroud separately. Arrr!

Main Engine Tube

1. Glue t' BT55 centerin' rings on main engine tube. Let dry. Blimey!
2. You'll want t' "dry fit" main engine mount and make sure "spent engine" recessed inside BT55 about ¼". Ahoy!
3. Mark Bt55 where "engine Hook" will be, and cut a slot 1/8" x3/8". Ya scallywag! Avast! Blimey!
4. Glue main engine mount with engine hook lined up with slot in BT55. Ya scallywag!

Booster Engine Mount

1. Take 3" piece o' 24mm BT; then cut 1/8"x 3/8" slot in one end.
2. Lay "flat" side o' hook inline with slot and tape. *** I used a long piece o' old wiper blade for hook and cut t' length later. Well, blow me down!
3. Cut out 3 "rear shroud centerin' rings. Well, blow me down! ***Tip: when I cut out middle o' rings FIRST, I then took a spent engine and inserted and twisted t' check for a tight fit. Begad! Arrr! Then inserted engine in tube for support. Avast, me proud beauty! Ya scallywag!
4. Take largest aft rin' and glue over aft engine mount WITHOUT coverin' slot in t' mount. Blimey! Be careful nay t' get glue on motor!!
5. Glue middle and end centerin' rings and remove spent motor and let dry. Arrr!
6. While drying, matey, cut out aft shroud. Aye aye! (You will see I include pattern, showin' a "saw tooth design" on inside radius o' shroud. Cut design in shroud. Ahoy! Much easier t' glue.)
7. Shape shroud, me bucko, shiver me timbers, me hearties, tape together on inside. Blimey!
8. Fold "teeth" over t' inside and make a sharp crease. Begad! Straighten out. Aye aye! Begad!
9. After center rings on engine tube have dried, me bucko, take some glue and apply t' edges o' rings. Aye aye!
10. Take shroud and slip over engine assembly. Blimey! Be sure t' get completely in. Blimey!
11. Spread some glue on smallest centerin' rin' and fold shroud "teeth" down, me bucko, holdin' till set. Blimey! Aye aye! You may only be able t' do a few @ a time. Ahoy! Let dry Thoroughly. Avast!
12. Put a spent engine in "Main and aft " engine mounts.
13. Slide together, ya bilge rat, matey, linin' up "slots" in engine tubes. Aye aye! T' aft engine tube should slide over t' Main engine about ½" and stay in place. Blimey! ***Make sure aft Booster engine is as far forward as it will go WITHOUT disengagin' t' booster. Well, blow me down!
14. Mark t' aft engine hook , ya bilge rat, cut and bend t' correct size. Begad! Arrr!
15. Cut shock cord mount and glue shock cord t' it. Ahoy! Begad!
16. Slide "loose" end o' shock cord thru a BT55 coupler.
17. Glue Shock cord mount t' inside o' BT55 containin' engine mount far enough inside t' be able t' glue BT55 coupler. Avast! Glue Bt55 coupler and let dry. Avast, me proud beauty!
18. Cut other BT55 t' length so when t' two r put together , arrr, you have a rocket body 23" long, "without" aft shroud. Aye aye!
19. Cut out Main Body centerin' rings. (u can take spare piece o' BT55 t' check fit).
20. Take t' "fin template" and mark 3", me hearties, 3.5" rin' where it will engage each fin. Ya scallywag! ****Note: you can mark 4" rin' but, because o' size, it won't line up with other two rings. Begad! You will have t' do slots on this rin' once it is mounted.
21. Take care, arrr, cut a ¼" deep slot x 1/8" wide into each ring.
22. Mark 1st slot on each rin' with a #1 for reference. Aye aye!
23. Make a fin from 1/8" "Basewood/plywood" as a guide t' check fit o' fins. Begad! It will also b used t' as guide for slots, me bucko, and cut initial fin slots in 4" ring.
    • ***You may want t' fasten up aft shroud again w/spent motors t' check placement o' centerin' rings and fins.***

Fins and Body:

1. Cut out 8 fins, and use sealer if desired. Ya scallywag! Blimey! Blimey! Blimey!
2. Use fine guide and cut slots in each fin: 1" from aft o' fin, 1x1/4 deep. Ya scallywag! Blimey! Next one 7" from end.
3. Last slot is 2.5 " from previous slot and only 5/8" deep. Blimey!
4. These r initial slots. Arrr! You may have t' widen for proper fit. Blimey!
5. Slide center rings on BT one @ a time. Begad! Blimey! Ahoy! Blimey! ***If seems tight or binds, me hearties, arrr, matey, increase size o' hole slightly. Ahoy! Blimey! You can use a piece o' BT55 t' "shape" hole. Avast, me proud beauty! Blimey! (you want t' maintain a fairly tight fit).
6. Space rings approximately same distance as slots on fin. Ahoy!
7. "Orientate" all 3 rings with #1's lined up. Begad! Ya scallywag!
8. Take your "Guide Fin", ( t' one made from plywood), and check slot lineup for first fin.
9. You'll have t' cut slots deeper in each ring, me hearties, me hearties, checkin' fit each time. Begad! Blimey! You may nay even need a slots for 4" ring, till ready t' glue on fins, arrr, matey, due t' a "redesign", matey, shiver me timbers, and linin' up o' fin with "center ring slots," I made for simplicity. Begad! Blimey! (make recess higher, about 1 ¼"). Begad! Blimey! Ya scallywag! Blimey!
10. After you get a good fit for t' fine on t' center rings, take a "real" fin and glue in #1 slots of rings. Begad! (I kept breakin' balsa fins, ya bilge rat, matey, matey, that why I recommended goin' t' a sturdier material, such as basswood or Tims Tech report #29, ya bilge rat, me bucko, shiver me timbers, gluin' "notebook paper" t' exterior o' fin first for strength). Begad!
11. Take guide fin and check next set o' slot, adjustin' for correct fit. Avast, me proud beauty!
12. Then glue 3 center rings in place.
13. Glue all 8 fins in place, checkin' fit first with "guide fin".
14. Cut out two "body templates". Make a slice at end o' each one ¼-3/4" deep, 1" from end on each side. Aye aye! Well, ya bilge rat, blow me down! Fold over @ slices and straighten out.
15. Dependin' upon which set o' fins you start with, me bucko, will determine what size template t' use, ya bilge rat, arrr, medium or large. Begad!
16. Lay template betwixt fins, and gently push down. Ya scallywag! It should hang out rear, betwixt fins 1", up to "slices."
17. Check front o' template and mark where template extends past fin. Avast! Blimey!
18. Cut on t' mark, me bucko, down t' ¼" fold mark on each side. Ya scallywag! Ya scallywag! Cut a "saw tooth" pattern in sides of body templates. Ahoy! Ya scallywag! Makes for easier gluin' and smoothin' out. ***see photo"***
19. Before gluin' fins, I made "fin supports," ½" x 1 ¼", and glue betwixt ends of fins. Begad! Ya scallywag! Also, made a bevel on each end. Avast! **See photo**
20. Glue in place and repeat for each set o' fins. Avast! ***remember t' check fit! (Center on BT) too. Aye aye! Ya scallywag! T' aft o' body template should be about ½-3/4" above body and aft shroud. Begad!
21. Cut out "body templates," with "saw-tooth" design on edges and glue betwixt fins. Avast, me proud beauty!
22. Main Body Shroud: As I stated in beginning, nay happy with t' way this one turned out. Blimey! Blimey! You may want t' shorten or find a different material or wrap around a "form" t' keep smooth. Also, me hearties, use same "saw-tooth" design for edges before gluin' in shape o' cone. Ya scallywag! Blimey! Once glue, let DRY THOROUGHLY. Avast, ya bilge rat, me proud beauty! Blimey!
23. I fitted over main body tube t' fins. Avast! Blimey! I marked where touched fins and cut slits about 1" long, me hearties, me bucko, in shroud. Keep fittin' till you get a tight fit into slots, then glue and let dry thoroughly. Ya scallywag!
24. Now comes a tricky part. Begad! Begad! Seams that r formed betwixt "fins, body templates, arrr, main shroud have t' be "filled." I opted t' use "Elmers wood filler" and nay happy with result. Ahoy! Begad! Friend recommended these tiny silicone beads you mix w/epoxy. Arrr! Strong, light, and easy t' sand after hardened.
25. After seams dry, shiver me timbers, sand till smooth.

Nosecone Fins:

1. Looking @ picture o' t' rocket I was copying, "upper fins" aren't really in nosecone but, I liked this location better. (You can opt t' move out o' nosecone, down body a few inches in "same configuration.)
2. Cut slits in nose cone ½" from end o' "open" nosecone, arrr, about 2" long and 3/16-1/4" wide. Well, blow me down! Ya scallywag! ** b careful nay t' cut all t' way thru t' end o' nosecone**. I mounted a piece o' 1" aluminum angle iron t' a piece o' wood and clamped t' me table as a guide. Avast!
3. Fit fins in slots one @ a time, trimmin' slots till fins fit. Well, blow me down! Remove fins and put a ball o' clay in tip of nosecone and press into place. Well, blow me down!
4. Replace fins 1 @ a time til they "touch" in middle o' nosecone and glue. Avast! (I opted for "gorilla glue" type). It foams up and becomes very strong). Begad! Let dry. Blimey! Arrr!

Nose Cone:

1. Keep addin' balls o' clay, fillin' void in nosecone, shiver me timbers, shiver me timbers, and pressin' into place. Ya scallywag! Blimey! ****remember t' allow room for end o' nose cone t' slide in.****
2. Also, me hearties, as you r fillin' void, assemble nosecone and check for CG with motors in main and booster BT's. Begad! Well, blow me down! (goin' to take a few ounces o' clay t' fill and balance rocket so CG approx. Ya scallywag! in middle.)
3. Once clay pressed into place and you r satisfied w/location o' CG, ya bilge rat, assemble nosecone.

Finishing:

1. Get 8 "regular" bic pen caps and cut off "pocket clip."
2. Paint rocket color o' preference. Ya scallywag!
3. After you r sure you have color o' rocket and finished painting, shiver me timbers, sand a flat spot on each "pen cap," and glue in place betwixt each fin above booster shroud. Well, blow me down! Ahoy! Blimey! (These pen caps simulate 8 motors o' rocket).
4. Prep rocket and you r ready t' fly. Ahoy! Arrr!
5. I would rate this build a 5++. Aye aye! Very difficult. Ahoy!

Flight:

My first flight was very successful. Avast! Blimey! I used a E9-4. Avast, me proud beauty! Blimey!

Preparation a little different than usual but, me hearties, shiver me timbers, easy. Ya scallywag! After loadin' an 18" parachute, dusted with baby powder, and t' wadding, I loaded t' engine. Aye aye! I loaded it into t' booster from t' "inside." (T' E9 is a much longer motor than t' D.) Then I applied a little maskin' tape t' t' end for a "friction fit," and inserted it into main rocket body. Aye aye! It flew great! Relatively straight for t' design, matey, 11 fins, shiver me timbers, and t' weight. Begad!

T' shock cord, attached t' rocket, was Keelhaul®©™. Then an elastic, tied t' t' Keelhaul®©™, which proved t' b t' weak. (will explain in next flight). Well, shiver me timbers, blow me down!

Parachute deployed perfectly and landed about 30 yards away.

SECOND FLIGHT

Another story. I designed this rocket t' be an optional 2-stage. Ahoy! Blimey! Blimey! Blimey! I prepped t' parachute t' same way. Avast, me proud beauty! Blimey! Then taped t' booster, a D12-0, shiver me timbers, t' t' main motor, arrr, a D12-3, with scotch tape, matey, and put a small slit in it, t' help with separation. Begad! Blimey! Once motors finished, I loaded it in booster stage first, from t' "inside." Then added some maskin' tape t' t' main motor and "friction fit" it into main rocket. Arrr! Blimey! For whatever reason I couldn't get motors all t' way in t' main rocket body. ( I believe I used too much tape). Begad! Blimey! Well, blow me down! Blimey! At launch, ya bilge rat, shiver me timbers, it flew down range, weathercocked. Ya scallywag! Blimey! Then deployed nosecone & parachute at a very low altitude o' about 50 ft. Begad! Blimey! T' extreme weight of rocket snapped shock cord and rocket crashed. Avast, me proud beauty! Blimey! I'll be usin' a much heavier, me hearties, and longer cord for t' next flight. Well, blow me down! Blimey! Still content with flight because it sustained minimal damage. Ahoy! Blimey! This was me first 2-stage rocket o' me own design.

THIRD FLIGHT

My third launch went absolutely perfect!! After addin' a 1/4" "heavy" shock cord, me bucko, I prepped rocket same way, shiver me timbers, with same motors. Well, blow me down! Blimey! A D12-0 Booster, taped t' a D12-3 Main. Ahoy! (Just make sure you have enough tape around main motor for "friction fit," and it's taped t' booster. Ahoy! Motors ***all t' way in*** main rocket. Slit cut in tape. Well, blow me down! Arrr! Picture perfect flight!! Booster took it t' a height o' o' about 75-100' and main an additional 100-200 ft. Perfect chute deployment and soft landin' about 75' away. Begad! Blimey!

Summary:

Pros: Challenge t' design and build.Impressive liftoff w/2stages.

Cons: Very time consuming. Begad! Blimey! Blimey! Blimey! Built a smaller version first t' get aquainted with a "building technique" for addin' 11 fins! Blimey! Blimey! Blimey! Highly reccommend when tacklin' a new build when in experienced. Alighnin' body panels betwixt fins a pain!

At almost 14 ozs., me bucko, I would opt for a E30-4 motor for 1st flight. Arrr! (E9-4) went well today. (use a spent motor in main body and tape E t' it in booster stage, (friction fit spent motor). Arrr! Ya scallywag! *****1/4" launch rod only!!****. Ahoy! Ya scallywag! 18" chute minimum!

Other:
Highly recommend "apogeerockets" tech report #29, matey, "Take your rocket t' supersonic speeds", shiver me timbers, for durability o' fins. Motor stagin' critical! Must b completely in main body so aft shroud close enough t' it. Ahoy! Avast! Used two 1/4x 2" soda straws on a fin for launch lugs.