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

My 1st test flight was a disaster. Begad! (Remember, 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.

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. Ya scallywag! Avast, me proud beauty! Also, Highly recommended buildin' a prototype, especially in me case. My submission for t' "rocket o' t' future" has 12 fins! Never came close t' design such a complex rocket before. Blimey!

Construction:

PARTS LIST:

• 24mm engine block
• 1 engine hooks
• 1 sheet o' foam board, 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. Ahoy! Hope you find this rocket as much o' a challenge t' build as I found to design it, me bucko, without t' help o' any "Cad software." If anyone cares t' "plug" these measurements into a cad program, shiver me timbers, me hearties, I would be very curious as t' t' result. I did use EMRR "Calculators" for t' shrouds and centerin' rings. I thank Nick for makin' available because without them, arrr, couldn't have made this design. Blimey! Blimey!

This design is for "Personal use only" and nay for resale, me bucko, with express permission o' myself, matey, matey, shiver me timbers, Glenn Roth. Ahoy! Begad!

I stated in "parts" section that t' balsa is very fragile. Begad! Blimey! Just discovered Tech Report # 29, from www.apogeerockets.com; "Take your rocket t' Supersonic Speeds. Avast! " 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. Aye aye! Well, blow me down! Options exist. Well, blow me down!

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

Main Engine Tube

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

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

Nosecone Fins:

1. Looking @ picture o' t' rocket I was copying, ya bilge rat, shiver me timbers, "upper fins" aren't really in nosecone but, I liked this location better. Avast, me proud beauty! Arrr! (You can opt t' move out o' nosecone, me hearties, matey, 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. ** 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. Ahoy!
3. Fit fins in slots one @ a time, ya bilge rat, trimmin' slots till fins fit. Arrr! Remove fins and put a ball o' clay in tip of nosecone and press into place. Ya scallywag!
4. Replace fins 1 @ a time til they "touch" in middle o' nosecone and glue. (I opted for "gorilla glue" type). Begad! It foams up and becomes very strong). Ya scallywag! Let dry. Well, blow me down!

Nose Cone:

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

Finishing:

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

Flight:

My first flight was very successful. Begad! Well, blow me down! I used a E9-4. Blimey!

Preparation a little different than usual but, me bucko, easy. Blimey! Avast, me proud beauty! After loadin' an 18" parachute, me hearties, dusted with baby powder, and t' wadding, I loaded t' engine. 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, matey, ya bilge rat, 11 fins, and t' weight. Arrr!

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

Parachute deployed perfectly and landed about 30 yards away.

SECOND FLIGHT

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

Summary:

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

Cons: Very time consuming. Blimey! Begad! 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. Ya scallywag! Alighnin' body panels betwixt fins a pain!

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

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