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. Ya scallywag! I gathered some cardboard, posterboard, shiver me timbers, and second hand parts, me hearties, etc. Avast, me proud beauty! It would have been ten times harder without t' EMRR "Calculators", for shrouds, etc. Avast! Avast! I chose cardboard figuring, "If I can get this t' fly without a cad program, me bucko, from t' heaviest material, I surely will be able t' build one in t' 24 MM scale. Also, cardboard a little easier t' work with than "foamboard."

My 1st test flight was a disaster. Ahoy! 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. 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, shiver me timbers, that u intend t' use on your final version." Mine did fly but, ya bilge rat, would have saved a lot o' aggravation and speeded up t' build. Also, Highly recommended buildin' a prototype, ya bilge rat, ya bilge rat, arrr, especially in me case. Arrr! 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, matey, ya bilge rat, 20x30x1/4"
• 2 sheets o' poster board, me hearties, 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, matey, 4"x"36"x1/8 balsa sheets/basswood
• 1 "quest" egglofter nosecone
• 1 (18") parachute, me hearties, & 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. Aye aye! 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, me hearties, I would be very curious as t' t' result. Avast! Well, ya bilge rat, blow me down! I did use EMRR "Calculators" for t' shrouds and centerin' rings. 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 hearties, with express permission o' myself, matey, Glenn Roth. Blimey! Blimey! 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. Avast, me proud beauty! Well, blow me down! " 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. Blimey! Options exist. Begad!

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

Main Engine Tube

1. Glue t' BT55 centerin' rings on main engine tube. Avast, arrr, me proud beauty! Let dry.
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, and cut a slot 1/8" x3/8".
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. Aye aye!
2. Lay "flat" side o' hook inline with slot and tape. Ya scallywag! Blimey! *** I used a long piece o' old wiper blade for hook and cut t' length later.
3. Cut out 3 "rear shroud centerin' rings. ***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. Blimey! Then inserted engine in tube for support. Ahoy! Avast!
4. Take largest aft rin' and glue over aft engine mount WITHOUT coverin' slot in t' mount. Ya scallywag! Be careful nay t' get glue on motor!!
5. Glue middle and end centerin' rings and remove spent motor and let dry. Well, blow me down!
6. While drying, cut out aft shroud. (You will see I include pattern, showin' a "saw tooth design" on inside radius o' shroud. Begad! Cut design in shroud. Much easier t' glue.)
7. Shape shroud, tape together on inside.
8. Fold "teeth" over t' inside and make a sharp crease. Aye aye! Straighten out. Begad! Begad!
9. After center rings on engine tube have dried, me bucko, take some glue and apply t' edges o' rings. Avast! Well, blow me down! Blimey!
10. Take shroud and slip over engine assembly. Avast! Be sure t' get completely in. Well, blow me down!
11. Spread some glue on smallest centerin' rin' and fold shroud "teeth" down, me hearties, matey, me bucko, holdin' till set. Ahoy! Begad! You may only be able t' do a few @ a time. Let dry Thoroughly. Arrr!
12. Put a spent engine in "Main and aft " engine mounts.
13. Slide together, linin' up "slots" in engine tubes. Blimey! T' aft engine tube should slide over t' Main engine about ½" and stay in place. ***Make sure aft Booster engine is as far forward as it will go WITHOUT disengagin' t' booster.
14. Mark t' aft engine hook , me hearties, me hearties, ya bilge rat, cut and bend t' correct size. Arrr! Avast!
15. Cut shock cord mount and glue shock cord t' it.
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. Ya scallywag! 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.
19. Cut out Main Body centerin' rings. (u can take spare piece o' BT55 t' check fit). Aye aye!
20. Take t' "fin template" and mark 3", me bucko, 3.5" rin' where it will engage each fin. Begad! Well, blow me down! ****Note: you can mark 4" rin' but, me hearties, me hearties, because o' size, matey, it won't line up with other two rings. Begad! You will have t' do slots on this rin' once it is mounted. Arrr!
21. Take care, cut a ¼" deep slot x 1/8" wide into each ring.
22. Mark 1st slot on each rin' with a #1 for reference.
23. Make a fin from 1/8" "Basewood/plywood" as a guide t' check fit o' fins. It will also b used t' as guide for slots, shiver me timbers, 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. Begad!
2. Use fine guide and cut slots in each fin: 1" from aft o' fin, ya bilge rat, 1x1/4 deep. Avast, me proud beauty! Well, arrr, blow me down! Next one 7" from end. Avast, me proud beauty! Arrr!
3. Last slot is 2.5 " from previous slot and only 5/8" deep. Aye aye!
4. These r initial slots. You may have t' widen for proper fit. Aye aye! Blimey! Blimey! Blimey!
5. Slide center rings on BT one @ a time. ***If seems tight or binds, increase size o' hole slightly. Aye aye! Ahoy! You can use a piece o' BT55 t' "shape" hole. Aye aye! (you want t' maintain a fairly tight fit). Begad!
6. Space rings approximately same distance as slots on fin. Aye aye!
7. "Orientate" all 3 rings with #1's lined up. Arrr! Blimey!
8. Take your "Guide Fin", shiver me timbers, ( t' one made from plywood), ya bilge rat, 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, me bucko, till ready t' glue on fins, due t' a "redesign", shiver me timbers, and linin' up o' fin with "center ring slots," I made for simplicity. Aye aye! (make recess higher, ya bilge rat, me bucko, about 1 ¼"). Well, blow me down! Aye aye!
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. Begad! Ya scallywag! (I kept breakin' balsa fins, 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). Avast!
11. Take guide fin and check next set o' slot, me hearties, adjustin' for correct fit. Ya scallywag!
12. Then glue 3 center rings in place. Aye aye! Begad!
13. Glue all 8 fins in place, checkin' fit first with "guide fin". Ahoy!
14. Cut out two "body templates". Avast! Make a slice at end o' each one ¼-3/4" deep, 1" from end on each side. Ya scallywag! Aye aye! Fold over @ slices and straighten out.
15. Dependin' upon which set o' fins you start with, will determine what size template t' use, shiver me timbers, arrr, medium or large. Ahoy! Ya scallywag!
16. Lay template betwixt fins, and gently push down. It should hang out rear, shiver me timbers, betwixt fins 1", ya bilge rat, up to "slices."
17. Check front o' template and mark where template extends past fin. Blimey!
18. Cut on t' mark, shiver me timbers, down t' ¼" fold mark on each side. Cut a "saw tooth" pattern in sides of body templates. Avast, me proud beauty! Ya scallywag! Makes for easier gluin' and smoothin' out. Aye aye! ***see photo"***
19. Before gluin' fins, I made "fin supports," ½" x 1 ¼", matey, and glue betwixt ends of fins. Also, made a bevel on each end. Avast! **See photo**
20. Glue in place and repeat for each set o' fins. Begad! ***remember t' check fit! (Center on BT) too. Well, blow me down! T' aft o' body template should be about ½-3/4" above body and aft shroud. Begad!
21. Cut out "body templates," with "saw-tooth" design on edges and glue betwixt fins. Aye aye! Begad!
22. Main Body Shroud: As I stated in beginning, me hearties, 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. Also, use same "saw-tooth" design for edges before gluin' in shape o' cone. Begad! Begad! Once glue, let DRY THOROUGHLY. Avast, me proud beauty!
23. I fitted over main body tube t' fins. I marked where touched fins and cut slits about 1" long, shiver me timbers, in shroud. Keep fittin' till you get a tight fit into slots, then glue and let dry thoroughly. Begad! Blimey! Blimey!
24. Now comes a tricky part. Well, blow me down! Blimey! Blimey! Blimey! Blimey! Blimey! Seams that r formed betwixt "fins, body templates, arrr, main shroud have t' be "filled." I opted t' use "Elmers wood filler" and nay happy with result. Avast, me proud beauty! Blimey! Blimey! Blimey! Friend recommended these tiny silicone beads you mix w/epoxy. Avast, me proud beauty! Blimey! Blimey! Blimey! Strong, light, and easy t' sand after hardened.
25. After seams dry, sand till smooth. Begad!

Nosecone Fins:

1. Looking @ picture o' t' rocket I was copying, "upper fins" aren't really in nosecone but, I liked this location better. Arrr! (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. Well, blow me down! ** 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. Arrr!
3. Fit fins in slots one @ a time, trimmin' slots till fins fit. Blimey! Remove fins and put a ball o' clay in tip of nosecone and press into place.
4. Replace fins 1 @ a time til they "touch" in middle o' nosecone and glue. Begad! (I opted for "gorilla glue" type). Begad! It foams up and becomes very strong). Let dry. Arrr!

Nose Cone:

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

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, shiver me timbers, sand a flat spot on each "pen cap," and glue in place betwixt each fin above booster shroud. Blimey! (These pen caps simulate 8 motors o' rocket). Avast, me proud beauty! Aye aye!
4. Prep rocket and you r ready t' fly. Arrr!
5. I would rate this build a 5++. Very difficult.

Flight:

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

Preparation a little different than usual but, easy. Aye aye! After loadin' an 18" parachute, dusted with baby powder, and t' wadding, me hearties, I loaded t' engine. Well, blow me down! 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. Blimey! Blimey! It flew great! Relatively straight for t' design, shiver me timbers, arrr, ya bilge rat, 11 fins, and t' weight. Avast!

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

Parachute deployed perfectly and landed about 30 yards away. Avast, me proud beauty!

SECOND FLIGHT

Another story. Avast, shiver me timbers, me proud beauty! I designed this rocket t' be an optional 2-stage. Avast, me proud beauty! I prepped t' parachute t' same way. Begad! Then taped t' booster, a D12-0, t' t' main motor, a D12-3, with scotch tape, and put a small slit in it, me hearties, t' help with separation. Aye aye! Aye aye! 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. Well, blow me down! Ya scallywag! 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, it flew down range, weathercocked. Aye aye! 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. Aye aye! 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. Well, blow me down! A D12-0 Booster, matey, 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. Well, blow me down! Blimey! Motors ***all t' way in*** main rocket. Arrr! Arrr! 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! Ahoy!

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. Well, blow me down! Alighnin' body panels betwixt fins a pain!

At almost 14 ozs., I would opt for a E30-4 motor for 1st flight. Avast, me proud beauty! (E9-4) went well today. Ya scallywag! (use a spent motor in main body and tape E t' it in booster stage, (friction fit spent motor). Ahoy! Arrr! *****1/4" launch rod only!!****. 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! Aye aye! Used two 1/4x 2" soda straws on a fin for launch lugs.