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

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

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

Construction:

PARTS LIST:

• 24mm engine block
• 1 engine hooks
• 1 sheet o' foam board, 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, shiver me timbers, & 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. Avast! 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, I would be very curious as t' t' result. Blimey! I did use EMRR "Calculators" for t' shrouds and centerin' rings. Arrr! Well, blow me down! I thank Nick for makin' available because without them, couldn't have made this design.

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

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. Ya scallywag! Arrr! " 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. Avast, me proud beauty! Options exist.

**Not happy with way main "body shroud" turned out. Begad! Aye aye! 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, make templates, and gather followin' tools: sharp razor knife, metal ruler, scissors, ya bilge rat, carpenters square, 2 "spent D" engines, adhesive spray, (worn out windshield wiper. Avast! Aye aye! For engine hooks)., ya bilge rat, protractor, and compass.
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. Arrr! I have increased length from 3 t' 3 ½ inches or longer, arrr, 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. Blimey! Blimey! I'm sure you can use one but, matey, matey, have t' "dry fit" b 4 assembly.*** I've discovered that with t' aft "body panels", extendin' an inch, me bucko, it's very difficult t' use an engine hook. Well, shiver me timbers, blow me down! Blimey! I've since elected t' slip "main motor" into booster engine mount, arrr, and tape. Ahoy! T' tape will require a "slit" into it, ya bilge rat, so makes easy separation. Blimey! Blimey!
3. Glue 24mm engine block into end o' engine tube w/engine hook stickin' into it. Avast, me proud beauty!
   • Option*** This designed as a "two stage". Ahoy! If you want an easier conversion t' single stage, ya bilge rat, you may want t' insert "booster engine tube" in a section o' BT-55. Begad! Then usin' a BT-55 coupler, ya bilge rat, fasten t' engine tubes together. (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. Well, blow me down! Begad! Let dry.
2. You'll want t' "dry fit" main engine mount and make sure "spent engine" recessed inside BT55 about ¼". Begad! Blimey! Begad! Blimey!
3. Mark Bt55 where "engine Hook" will be, me hearties, matey, and cut a slot 1/8" x3/8". Begad! Ahoy!
4. Glue main engine mount with engine hook lined up with slot in BT55. Arrr! Blimey! Arrr! Blimey! Blimey! Blimey!

Booster Engine Mount

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

Nosecone Fins:

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

Nose Cone:

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

Finishing:

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

Flight:

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

Preparation a little different than usual but, matey, easy. After loadin' an 18" parachute, me hearties, arrr, matey, 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, 11 fins, and t' weight. Aye aye!

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

Parachute deployed perfectly and landed about 30 yards away.

SECOND FLIGHT

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

Summary:

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

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

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

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