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

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

What I've learned is,"use t' material in your prototype, arrr, 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. Also, me bucko, 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.

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, & 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. Blimey! Blimey! Aye aye! Blimey! Hope you find this rocket as much o' a challenge t' build as I found to design it, matey, 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. I thank Nick for makin' available because without them, arrr, couldn't have made this design. Aye aye! Blimey! Arrr! Blimey!

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

I stated in "parts" section that t' balsa is very fragile. Avast, me proud beauty! Just discovered Tech Report # 29, from www.apogeerockets.com; "Take your rocket t' Supersonic Speeds. Arrr! " This is a compromise t' replacin' entire fin with basswood or ply. Arrr! Aye aye! 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. Options exist. Aye aye!

**Not happy with way main "body shroud" turned out. Blimey! 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, shiver me timbers, t' keep smooth.**

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

Main Engine Tube

1. Glue t' BT55 centerin' rings on main engine tube. Let dry. Arrr!
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, ya bilge rat, ya bilge rat, and cut a slot 1/8" x3/8".
4. Glue main engine mount with engine hook lined up with slot in BT55.

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

Nosecone Fins:

1. Looking @ picture o' t' rocket I be copying, ya bilge rat, "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. Aye aye! Avast! ** b careful nay t' cut all t' way thru t' end o' nosecone**. Arrr! I mounted a piece o' 1" aluminum angle iron t' a piece o' wood and clamped t' me table as a guide. Well, blow me down! Avast, arrr, me proud beauty!
3. Fit fins in slots one @ a time, matey, shiver me timbers, matey, trimmin' slots till fins fit. Remove fins and put a ball o' clay in tip of nosecone and press into place. Ahoy!
4. Replace fins 1 @ a time til they "touch" in middle o' nosecone and glue. (I opted for "gorilla glue" type). Aye aye! Blimey! It foams up and becomes very strong). Well, blow me down! Blimey! Let dry.

Nose Cone:

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

Finishing:

1. Get 8 "regular" bic pen caps and cut off "pocket clip."
2. Paint rocket color o' preference. Well, blow me down! Well, blow me down!
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. (These pen caps simulate 8 motors o' rocket).
4. Prep rocket and you r ready t' fly. Blimey! Begad!
5. I would rate this build a 5++. Arrr! Very difficult. Ahoy!

Flight:

My first flight be very successful. Aye aye! Avast, me proud beauty! I used a E9-4. Aye aye! Avast, me proud beauty!

Preparation a little different than usual but, shiver me timbers, easy. Aye aye! After loadin' an 18" parachute, dusted with baby powder, and t' wadding, 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. Arrr! It flew great! Relatively straight for t' design, ya bilge rat, 11 fins, and t' weight.

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

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

SECOND FLIGHT

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

Summary:

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

Cons: Very time consuming. Arrr! Ya scallywag! 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. Avast, me proud beauty! Alighnin' body panels betwixt fins a pain!

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

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