Brief:
11 "Finned" rocket that can be launched on a single "E" or staged (D12-0, ya bilge rat, 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. Begad! I gathered some cardboard, me hearties, posterboard, and second hand parts, ya bilge rat, etc. Begad! Well, blow me down! It would have been ten times harder without t' EMRR "Calculators", matey, me hearties, for shrouds, matey, etc. Begad! Blimey! I chose cardboard figuring, "If I can get this t' fly without a cad program, shiver me timbers, from t' heaviest material, ya bilge rat, I surely will be able t' build one in t' 24 MM scale. Avast, me proud beauty! Also, cardboard a little easier t' work with than "foamboard."

My 1st test flight was a disaster. Aye aye! Blimey! (Remember, shiver me timbers, shiver me timbers, me bucko, 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!

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. Also, me bucko, me bucko, Highly recommended buildin' a prototype, especially in me case. Blimey! Blimey! 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! Blimey! Avast! Blimey!

Construction:

PARTS LIST:

• 24mm engine block
• 1 engine hooks
• 1 sheet o' foam board, matey, 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, shiver me timbers, shiver me timbers, 4"x"36"x1/8 balsa sheets/basswood
• 1 "quest" egglofter nosecone
• 1 (18") parachute, & 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. Ya scallywag! Blimey! Hope you find this rocket as much o' a challenge t' build as I found to design it, without t' help o' any "Cad software." If anyone cares t' "plug" these measurements into a cad program, me bucko, I would be very curious as t' t' result. Avast! Blimey! I did use EMRR "Calculators" for t' shrouds and centerin' rings. I thank Nick for makin' available because without them, me hearties, couldn't have made this design. Blimey! Blimey! Avast, shiver me timbers, me proud beauty! Blimey!

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

I stated in "parts" section that t' balsa is very fragile. Begad! Begad! Just discovered Tech Report # 29, arrr, from www.apogeerockets.com; "Take your rocket t' Supersonic Speeds. Blimey! Ya scallywag! " This is a compromise t' replacin' entire fin with basswood or ply. 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. Begad! Options exist. Well, blow me down! Begad!

**Not happy with way main "body shroud" turned out. Begad! 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, t' keep smooth.**

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

Main Engine Tube

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

Booster Engine Mount

1. Take 3" piece o' 24mm BT; then cut 1/8"x 3/8" slot in one end. Begad! Aye aye! Blimey!
2. Lay "flat" side o' hook inline with slot and tape. Ahoy! Begad! *** I used a long piece o' old wiper blade for hook and cut t' length later. Begad! Ahoy!
3. Cut out 3 "rear shroud centerin' rings. Avast! Arrr! ***Tip: when I cut out middle o' rings FIRST, ya bilge rat, I then took a spent engine and inserted and twisted t' check for a tight fit. Then inserted engine in tube for support. Arrr! Ahoy!
4. Take largest aft rin' and glue over aft engine mount WITHOUT coverin' slot in t' mount. Ahoy! Begad! 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, shiver me timbers, matey, cut out aft shroud. (You will see I include pattern, me hearties, arrr, showin' a "saw tooth design" on inside radius o' shroud. Avast! Cut design in shroud. Much easier t' glue.)
7. Shape shroud, me hearties, tape together on inside. Avast, me proud beauty!
8. Fold "teeth" over t' inside and make a sharp crease. Begad! Straighten out. Arrr!
9. After center rings on engine tube have dried, me hearties, take some glue and apply t' edges o' rings.
10. Take shroud and slip over engine assembly. Be sure t' get completely in. Ya scallywag!
11. Spread some glue on smallest centerin' rin' and fold shroud "teeth" down, holdin' till set. Blimey! Begad! You may only be able t' do a few @ a time. Let dry Thoroughly.
12. Put a spent engine in "Main and aft " engine mounts.
13. Slide together, arrr, ya bilge rat, linin' up "slots" in engine tubes. Ya scallywag! T' aft engine tube should slide over t' Main engine about ½" and stay in place. Ahoy! ***Make sure aft Booster engine is as far forward as it will go WITHOUT disengagin' t' booster. Ya scallywag!
14. Mark t' aft engine hook , matey, cut and bend t' correct size. Aye aye!
15. Cut shock cord mount and glue shock cord t' it. Avast!
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. Arrr! Glue Bt55 coupler and let dry.
18. Cut other BT55 t' length so when t' two r put together , you have a rocket body 23" long, "without" aft shroud. Arrr!
19. Cut out Main Body centerin' rings. Ya scallywag! Arrr! (u can take spare piece o' BT55 t' check fit). Begad! Arrr!
20. Take t' "fin template" and mark 3", ya bilge rat, 3.5" rin' where it will engage each fin. Arrr! ****Note: you can mark 4" rin' but, me bucko, because o' size, it won't line up with other two rings. Ahoy! Begad! You will have t' do slots on this rin' once it is mounted. Begad!
21. Take care, cut a ¼" deep slot x 1/8" wide into each ring. Begad!
22. Mark 1st slot on each rin' with a #1 for reference. Arrr! Begad!
23. Make a fin from 1/8" "Basewood/plywood" as a guide t' check fit o' fins. Ahoy! Blimey! It will also b used t' as guide for slots, ya bilge rat, ya bilge rat, 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. Avast, me proud beauty!
2. Use fine guide and cut slots in each fin: 1" from aft o' fin, ya bilge rat, 1x1/4 deep. Arrr! Avast! Next one 7" from end. Avast, me proud beauty! Begad!
3. Last slot is 2.5 " from previous slot and only 5/8" deep. Begad!
4. These r initial slots. You may have t' widen for proper fit. Aye aye! Blimey! Avast! Blimey! Blimey! Blimey!
5. Slide center rings on BT one @ a time. Ahoy! Begad! ***If seems tight or binds, increase size o' hole slightly. You can use a piece o' BT55 t' "shape" hole. Begad! Ya scallywag! (you want t' maintain a fairly tight fit). Avast, me proud beauty! Aye aye!
6. Space rings approximately same distance as slots on fin. Ahoy! Avast!
7. "Orientate" all 3 rings with #1's lined up. Arrr!
8. Take your "Guide Fin", ( t' one made from plywood), me bucko, and check slot lineup for first fin.
9. You'll have t' cut slots deeper in each ring, checkin' fit each time. You may nay even need a slots for 4" ring, till ready t' glue on fins, due t' a "redesign", me bucko, matey, and linin' up o' fin with "center ring slots," I made for simplicity. Begad! (make recess higher, shiver me timbers, about 1 ¼"). Avast, shiver me timbers, me proud beauty!
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. Well, blow me down! Blimey! (I kept breakin' balsa fins, that why I recommended goin' t' a sturdier material, such as basswood or Tims Tech report #29, shiver me timbers, gluin' "notebook paper" t' exterior o' fin first for strength). Begad! Blimey!
11. Take guide fin and check next set o' slot, adjustin' for correct fit. Arrr!
12. Then glue 3 center rings in place. Well, blow me down!
13. Glue all 8 fins in place, me hearties, matey, checkin' fit first with "guide fin". Blimey!
14. Cut out two "body templates". Avast! Make a slice at end o' each one ¼-3/4" deep, ya bilge rat, 1" from end on each side. Ya scallywag! Fold over @ slices and straighten out.
15. Dependin' upon which set o' fins you start with, will determine what size template t' use, arrr, medium or large.
16. Lay template betwixt fins, arrr, and gently push down. Ahoy! It should hang out rear, arrr, betwixt fins 1", me hearties, shiver me timbers, me hearties, up to "slices."
17. Check front o' template and mark where template extends past fin. Blimey!
18. Cut on t' mark, down t' ¼" fold mark on each side. Avast, me proud beauty! Arrr! Cut a "saw tooth" pattern in sides of body templates. Ahoy! Blimey! Makes for easier gluin' and smoothin' out. Avast! ***see photo"***
19. Before gluin' fins, I made "fin supports," ½" x 1 ¼", shiver me timbers, and glue betwixt ends of fins. Ya scallywag! Avast! Also, made a bevel on each end. **See photo**
20. Glue in place and repeat for each set o' fins. Aye aye! Avast, arrr, me proud beauty! ***remember t' check fit! (Center on BT) too. Begad! T' aft o' body template should be about ½-3/4" above body and aft shroud. Aye aye! Arrr!
21. Cut out "body templates," with "saw-tooth" design on edges and glue betwixt fins. Avast!
22. Main Body Shroud: As I stated in beginning, matey, nay happy with t' way this one turned out. Arrr! You may want t' shorten or find a different material or wrap around a "form" t' keep smooth. Also, ya bilge rat, use same "saw-tooth" design for edges before gluin' in shape o' cone. Begad! Once glue, let DRY THOROUGHLY. Well, blow me down!
23. I fitted over main body tube t' fins. Begad! Begad! I marked where touched fins and cut slits about 1" long, matey, in shroud. Keep fittin' till you get a tight fit into slots, shiver me timbers, then glue and let dry thoroughly. Begad!
24. Now comes a tricky part. Avast! Blimey! Seams that r formed betwixt "fins, shiver me timbers, body templates, main shroud have t' be "filled." I opted t' use "Elmers wood filler" and nay happy with result. Ya scallywag! Blimey! Begad! Blimey! Friend recommended these tiny silicone beads you mix w/epoxy. Strong, light, ya bilge rat, ya bilge rat, and easy t' sand after hardened.
25. After seams dry, sand till smooth. Avast!

Nosecone Fins:

1. Looking @ picture o' t' rocket I was copying, "upper fins" aren't really in nosecone but, I liked this location better. Begad! Blimey! Ya scallywag! Blimey! (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, me hearties, me bucko, about 2" long and 3/16-1/4" wide. ** b careful nay t' cut all t' way thru t' end o' nosecone**. Ahoy! Avast, me proud beauty! I mounted a piece o' 1" aluminum angle iron t' a piece o' wood and clamped t' me table as a guide. Arrr! Avast!
3. Fit fins in slots one @ a time, me bucko, trimmin' slots till fins fit. Arrr! Remove fins and put a ball o' clay in tip of nosecone and press into place. Avast, me proud beauty!
4. Replace fins 1 @ a time til they "touch" in middle o' nosecone and glue. Ahoy! (I opted for "gorilla glue" type). Ya scallywag! It foams up and becomes very strong). Begad! Ya scallywag! Let dry. Ahoy! Begad!

Nose Cone:

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

Finishing:

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

Flight:

My first flight was very successful. Aye aye! Blimey! I used a E9-4.

Preparation a little different than usual but, me bucko, easy. After loadin' an 18" parachute, me bucko, ya bilge rat, dusted with baby powder, and t' wadding, matey, I loaded t' engine. Ya scallywag! 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. It flew great! Relatively straight for t' design, 11 fins, and t' weight. Ya scallywag! Begad!

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

Parachute deployed perfectly and landed about 30 yards away. Arrr! Blimey! Avast! Blimey!

SECOND FLIGHT

Another story. I designed this rocket t' be an optional 2-stage. Arrr! I prepped t' parachute t' same way. Aye aye! Well, blow me down! Then taped t' booster, arrr, ya bilge rat, a D12-0, t' t' main motor, a D12-3, with scotch tape, and put a small slit in it, arrr, t' help with separation. Ahoy! 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. Begad! For whatever reason I couldn't get motors all t' way in t' main rocket body. Ya scallywag! ( I believe I used too much tape). Blimey! At launch, ya bilge rat, it flew down range, weathercocked. Avast, me proud beauty! Then deployed nosecone & parachute at a very low altitude o' about 50 ft. Begad! Avast, me bucko, me proud beauty! T' extreme weight of rocket snapped shock cord and rocket crashed. I'll be usin' a much heavier, matey, and longer cord for t' next flight. Ahoy! Still content with flight because it sustained minimal damage. Arrr! This be 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, shiver me timbers, me bucko, I prepped rocket same way, me bucko, with same motors. Avast! A D12-0 Booster, me bucko, taped t' a D12-3 Main. (Just make sure you have enough tape around main motor for "friction fit," and it's taped t' booster. Blimey! Motors ***all t' way in*** main rocket. Avast, me proud beauty! Slit cut in tape. Ya scallywag! Begad! 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! Begad!

Summary:

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

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

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

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