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

My 1st test flight was a disaster. Well, blow me down! (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. Begad! Blimey! Blimey! Last Saturday flew it again and success! Blimey! It only went 50 ft up but successfully deployed chute right before landing.

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

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, 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. Arrr! 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. I did use EMRR "Calculators" for t' shrouds and centerin' rings. Aye aye! Ahoy! I thank Nick for makin' available because without them, matey, couldn't have made this design. Ya scallywag!

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

I stated in "parts" section that t' balsa is very fragile. Just discovered Tech Report # 29, from www.apogeerockets.com; "Take your rocket t' Supersonic Speeds. " 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. Ya scallywag! Begad! Options exist. Arrr!

**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, t' keep smooth.**

1. Gather parts, arrr, ya bilge rat, matey, make templates, and gather followin' tools: sharp razor knife, metal ruler, me bucko, scissors, carpenters square, 2 "spent D" engines, shiver me timbers, adhesive spray, me hearties, (worn out windshield wiper. Aye aye! For engine hooks)., me hearties, ya bilge rat, ya bilge rat, protractor, arrr, arrr, and compass. Begad! Aye aye!
2. Cut two engine mounts from 24mm body tube. Ya scallywag! 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, arrr, in instructions. Arrr! You'll have increase length o' shroud accordingly.****
   • *** OPTION: I've since elected t' use a "friction fit", instead o' an engine hook, matey, ya bilge rat, ya bilge rat, on main motor. 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, 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, and tape. Begad! Blimey! T' tape will require a "slit" into it, so makes easy separation. Blimey!
3. Glue 24mm engine block into end o' engine tube w/engine hook stickin' into it.
   • Option*** This designed as a "two stage". Ya scallywag! Ya scallywag! If you want an easier conversion t' single stage, you may want t' insert "booster engine tube" in a section o' BT-55. Then usin' a BT-55 coupler, me hearties, fasten t' engine tubes together. Begad! (skip 1st /main engine tube.) It is much easier buildin' booster shroud separately.

Main Engine Tube

1. Glue t' BT55 centerin' rings on main engine tube. Avast! Let dry. Aye aye! Well, blow me down!
2. You'll want t' "dry fit" main engine mount and make sure "spent engine" recessed inside BT55 about ¼". Ahoy! Blimey!
3. Mark Bt55 where "engine Hook" will be, and cut a slot 1/8" x3/8". Ya scallywag! Avast!
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. Begad!
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.
3. Cut out 3 "rear shroud centerin' rings. Well, blow me down! Begad! ***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! Then inserted engine in tube for support. Begad!
4. Take largest aft rin' and glue over aft engine mount WITHOUT coverin' slot in t' mount. Aye aye! Be careful nay t' get glue on motor!!
5. Glue middle and end centerin' rings and remove spent motor and let dry.
6. While drying, arrr, matey, cut out aft shroud. Ya scallywag! Aye aye! (You will see I include pattern, me bucko, showin' a "saw tooth design" on inside radius o' shroud. Avast! Cut design in shroud. Arrr! Much easier t' glue.)
7. Shape shroud, shiver me timbers, shiver me timbers, tape together on inside. Arrr! Avast! Blimey!
8. Fold "teeth" over t' inside and make a sharp crease. Straighten out. Begad! Ya scallywag!
9. After center rings on engine tube have dried, take some glue and apply t' edges o' rings.
10. Take shroud and slip over engine assembly. Aye aye! Blimey! Be sure t' get completely in.
11. Spread some glue on smallest centerin' rin' and fold shroud "teeth" down, holdin' till set. Avast, me proud beauty! Blimey! You may only be able t' do a few @ a time. Well, blow me down! Blimey! Let dry Thoroughly. Blimey! Blimey! Avast! Blimey!
12. Put a spent engine in "Main and aft " engine mounts. Well, blow me down!
13. Slide together, ya bilge rat, linin' up "slots" in engine tubes. Aye aye! Blimey! T' aft engine tube should slide over t' Main engine about ½" and stay in place. Avast! Blimey! ***Make sure aft Booster engine is as far forward as it will go WITHOUT disengagin' t' booster. Ya scallywag! Blimey! Arrr! Blimey!
14. Mark t' aft engine hook , cut and bend t' correct size. Ahoy!
15. Cut shock cord mount and glue shock cord t' it.
16. Slide "loose" end o' shock cord thru a BT55 coupler. Ya scallywag!
17. Glue Shock cord mount t' inside o' BT55 containin' engine mount far enough inside t' be able t' glue BT55 coupler. Avast! Begad! Glue Bt55 coupler and let dry. Aye aye! Well, me hearties, blow me down!
18. Cut other BT55 t' length so when t' two r put together , you have a rocket body 23" long, "without" aft shroud. Begad! Blimey!
19. Cut out Main Body centerin' rings. Aye aye! (u can take spare piece o' BT55 t' check fit). Aye aye! Aye aye!
20. Take t' "fin template" and mark 3", 3.5" rin' where it will engage each fin. Well, blow me down! ****Note: you can mark 4" rin' but, because o' size, me hearties, it won't line up with other two rings. Well, blow me down! You will have t' do slots on this rin' once it is mounted. Ahoy!
21. Take care, ya bilge rat, ya bilge rat, cut a ¼" deep slot x 1/8" wide into each ring. Aye aye! Blimey!
22. Mark 1st slot on each rin' with a #1 for reference. Well, blow me down! Blimey! Avast! Blimey!
23. Make a fin from 1/8" "Basewood/plywood" as a guide t' check fit o' fins. Ya scallywag! It will also b used t' as guide for slots, matey, 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. Well, blow me down!
2. Use fine guide and cut slots in each fin: 1" from aft o' fin, 1x1/4 deep. Arrr! 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. You may have t' widen for proper fit.
5. Slide center rings on BT one @ a time. Ya scallywag! Aye aye! ***If seems tight or binds, increase size o' hole slightly. Well, blow me down! You can use a piece o' BT55 t' "shape" hole. (you want t' maintain a fairly tight fit). Arrr!
6. Space rings approximately same distance as slots on fin. Begad!
7. "Orientate" all 3 rings with #1's lined up. Arrr! Blimey!
8. Take your "Guide Fin", ( t' one made from plywood), shiver me timbers, and check slot lineup for first fin. Ahoy!
9. You'll have t' cut slots deeper in each ring, checkin' fit each time. Avast, me proud beauty! You may nay even need a slots for 4" ring, till ready t' glue on fins, shiver me timbers, due t' a "redesign", matey, and linin' up o' fin with "center ring slots," I made for simplicity. Ya scallywag! (make recess higher, about 1 ¼"). Avast! Well, blow me down!
10. After you get a good fit for t' fine on t' center rings, me hearties, take a "real" fin and glue in #1 slots of rings. Aye aye! Avast! (I kept breakin' balsa fins, arrr, that why I recommended goin' t' a sturdier material, such as basswood or Tims Tech report #29, me bucko, gluin' "notebook paper" t' exterior o' fin first for strength). Begad! Ya scallywag!
11. Take guide fin and check next set o' slot, shiver me timbers, me bucko, adjustin' for correct fit. Ahoy! Begad!
12. Then glue 3 center rings in place. Begad!
13. Glue all 8 fins in place, me bucko, arrr, checkin' fit first with "guide fin". Begad!
14. Cut out two "body templates". Make a slice at end o' each one ¼-3/4" deep, 1" from end on each side. Fold over @ slices and straighten out.
15. Dependin' upon which set o' fins you start with, will determine what size template t' use, medium or large. Well, blow me down!
16. Lay template betwixt fins, and gently push down. It should hang out rear, arrr, betwixt fins 1", up to "slices."
17. Check front o' template and mark where template extends past fin. Aye aye!
18. Cut on t' mark, matey, down t' ¼" fold mark on each side. Cut a "saw tooth" pattern in sides of body templates. Arrr! Makes for easier gluin' and smoothin' out. Ya scallywag! Well, blow me down! ***see photo"***
19. Before gluin' fins, I made "fin supports," ½" x 1 ¼", and glue betwixt ends of fins. Also, made a bevel on each end. Ya scallywag! **See photo**
20. Glue in place and repeat for each set o' fins. Begad! Begad! ***remember t' check fit! (Center on BT) too. T' aft o' body template should be about ½-3/4" above body and aft shroud. Well, matey, blow me down!
21. Cut out "body templates," with "saw-tooth" design on edges and glue betwixt fins. Begad!
22. Main Body Shroud: As I stated in beginning, arrr, nay happy with t' way this one turned out. Begad! Ahoy! Blimey! You may want t' shorten or find a different material or wrap around a "form" t' keep smooth. Also, use same "saw-tooth" design for edges before gluin' in shape o' cone. Once glue, arrr, let DRY THOROUGHLY. Ahoy! Blimey!
23. I fitted over main body tube t' fins. Arrr! Well, blow me down! Blimey! I marked where touched fins and cut slits about 1" long, in shroud. Keep fittin' till you get a tight fit into slots, ya bilge rat, me bucko, me hearties, then glue and let dry thoroughly. Ya scallywag! Blimey!
24. Now comes a tricky part. Avast, me proud beauty! Arrr! Seams that r formed betwixt "fins, arrr, me bucko, body templates, main shroud have t' be "filled." I opted t' use "Elmers wood filler" and nay happy with result. Avast, me proud beauty! Ya scallywag! Friend recommended these tiny silicone beads you mix w/epoxy. Begad! Strong, ya bilge rat, me bucko, light, arrr, and easy t' sand after hardened. Aye aye!
25. After seams dry, sand till smooth. Ahoy!

Nosecone Fins:

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

Nose Cone:

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

Finishing:

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

Flight:

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

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

T' shock cord, attached t' rocket, was Keelhaul®©™. Then an elastic, matey, tied t' t' Keelhaul®©™, shiver me timbers, which proved t' b t' weak. (will explain in next flight). Aye aye! Avast, arrr, me proud beauty!

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

SECOND FLIGHT

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

THIRD FLIGHT

My third launch went absolutely perfect!! Blimey! After addin' a 1/4" "heavy" shock cord, I prepped rocket same way, with same motors. Well, blow me down! A D12-0 Booster, ya bilge rat, taped t' a D12-3 Main. Avast, matey, me proud beauty! Blimey! (Just make sure you have enough tape around main motor for "friction fit," and it's taped t' booster. Motors ***all t' way in*** main rocket. Begad! Arrr! Blimey! Slit cut in tape. Picture perfect flight!! Blimey! 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. Ya scallywag! Avast! Blimey!

Summary:

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

Cons: Very time consuming. 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. Alighnin' body panels betwixt fins a pain!

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

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