Eric needed a new rocket. Arrr! Earlier in t' month I had launched his Lil’ Nuke on an H128 and it vanished. I told him we could buy a new one or he could design a rocket. Arrr! Well, blow me down! He likes short stubby rockets like t' Minie Magg and Fat Boy and since I couldn’t afford a Warlock he designed this:

It’s built usin' LOC Precision components. Aye aye! Blimey! T' construction is straight forward, basic, me hearties, and sturdy. Arrr! Blimey! T' rocket is designed t' fly on an G64 through J350. Blimey! Blimey! This would make a nice starter kit for someone who is wantin' t' expand beyond t' low and mid power kits available.

T' 21 1/2" BT needs t' be slotted for t' fins. Markin' t' BT is easy. Arrr! Tape 2 sheets o' notebook paper together lengthwise t' make one sheet about 14 inches long. Blimey! From t' 8 1/2 inch edge, ya bilge rat, measure two marks; One at 107mm and one at 214mm. Wrap this long sheet around t' BT so t' edges line up perfectly around t' circumference. Ya scallywag! Now transfer t' marks, shiver me timbers, includin' t' paper edge t' t' BT. Blimey! Aye aye! T' end o' t' paper and t' two marks should all be 107mm from each other.

To cut t' slots we utilized a length o' angle stock t' draw straight lines and use as a cuttin' guide. Ya scallywag! I taped t' angle t' t' BT and then used a very sharp x-acto t' make t' tube slots. Ya scallywag! Well, arrr, blow me down! T' slots are 7 3/4 inches long and 1/8th wide startin' at 1 inch from t' bottom o' t' BT.

Fin, ya bilge rat, arrr, Centerin' Rin' (CR) and Motor Mount Tube (MMT) T' fins are through t' wall (TTW) but do nay extend t' t' motor mount. Avast! Aye aye! We were usin' a set o' Minie Magg fins from a kit o' leftover parts. Arrr! Ya scallywag! (Crash repair) T' fins are locked into t' centerin' rings and are very sturdy. First slide t' CR’s into t' BT and make marks through t' fin slots onto t' edge o' t' CR’s. Also, make an index mark on t' BT and both CR’s so they can be oriented t' same way in t' future. Blimey! On t' upper CR, matey, arrr, me bucko, cut slots 8mm deep t' same thickness as t' fin material (1/8th in.) On t' fins cut slots 8mm deep and 1/8th in. Arrr! wide at 1 inch from t' top o' t' tab. (see photo)

Now, ya bilge rat, arrr, me hearties, bond t' upper CR into t' BT. I used Elmer's Yellow Wood Glue for all t' CR bonds. Avast! Glue t' fins t' t' upper CR t' locate it evenly and hold it in place while t' upper surface fillet dries. Aye aye! Turn t' rocket over and apply a fillet t' t' lower side o' t' CR.

Time t' think o' motor retention: Drill two 3/16 holes, me bucko, one on either side o' t' motor hole (1/4 - 1/2 inch away) in t' aft CR. Arrr! Ya scallywag! Apply a small amount o' CA t' t' wood surface and in t' hole. Begad! Seat t' "T-nuts", 6/32 x 1/4, into t' upper surface o' t' CR.

T' fins require internal fillets for strength. Aye aye! Arrr! (see photo) I found tiny moldin' at t' hobby store but small scraps o' balsa (1/8 x 1/8 x 6 in.) would work just as well. Avast, me proud beauty! Bond these strips t' t' fins and BT t' form a structural fillet. Avast, me proud beauty! Begad! When this is complete t' MMT and aft CR can be installed. Ya scallywag! Cut slots in t' aft CR t' capture t' fin tabs. T' slots need t' be as deep as t' fin tab sticks through t' BT wall at t' very bottom. Arrr! Ya scallywag! Smear glue on t' inside edge o' t' motor hole on t' upper CR and on t' MMT near t' top. Begad! Start t' aft CR onto t' MMT (at t' bottom end, me hearties, nay t' glued end) and insert this as a unit into t' upper CR. Arrr! Push t' MMT through t' upper CR. Blimey! Seat t' lower CR into t' BT until it hits t' fins. Avast, me proud beauty! (DO NOT ENGAGE THE SLOTS) Push t' MMT up until it’s only protrudin' down 1/4 inch from t' lower CR. Let t' rocket dry upside down, this will form t' fillet on t' upper CR, lower side. Ya scallywag! (If you put on enough glue)

Now t' aft CR can be removed with a wire hook in t' fin slot hole. Blimey! Smear glue on t' MMT, matey, BT, fin tabs and some on both edges (inner and outer) o' t' aft CR. Slide t' aft CR into place, arrr, engagin' t' fin tabs in t' slots. Begad! Aye aye! Let t' rocket stand upright t' form fillets on t' upper surface o' t' aft CR. Begad! Aye aye! Later, me bucko, apply fillets t' t' bottom o' t' aft CR at t' BT and MMT.

Recovery SystemMake a bulkhead / baffle out o' a CR or cut your own. Ahoy! If a stock CR is used a block plate must be cut t' plug t' big center hole. Arrr! Plywood is bonded over t' hole for this. Blimey! Avast! (see photo). Begad! Well, blow me down! Install a "U"-bolt or eyebolt (with t' big washer) into t' bulkhead after drillin' 12 1/4" or 8 3/8" holes in it. Arrr! I use strips o' fiberglass t' strengthen t' bond with t' BT but this is nay required. Another method is t' use a tube coupler installed above t' bulkhead t' keep it from de-bondin' under stress. Have t' kids finish their Cheerios or you finish t' Coco Puffs and cut a hunk o' t' box 3" x 12 3/8" and form it into a 4" dia tube. Well, me bucko, blow me down! Bond t' bulkhead into t' BT 6" down from t' top. Arrr! Make a fillet around t' edge and then bond t' coupler into t' tube above t' bulkhead.

I use 9/16" wide tubular nylon webbing, shiver me timbers, stock no. Avast! 472315 purchased on-line from REI for t' shock cord. Avast! 12 - 20 feet is about right. Ya scallywag! Attach it t' t' lower anchor with a quick-link. Well, blow me down! Attach t' chute near t' middle but nay exactly (off 2 feet) with a quick-link attached t' a loop tied into t' tubular.

Nose Cone Now for t' nose cone (NC): Cut t' base o' t' NC off within a 1/4 inch o' t' radius at t' bottom. Begad! Begad! (see photo) You want an open ended NC with as long as shoulder as possible. Avast, me proud beauty! Drill several (20-30) 1/16" holes in t' tip end o' t' NC 1/2" apart from one another. Blimey! Well, blow me down! All these holes should be within 2 1/4" from t' tip. Ya scallywag! Wrap several short (4-6") strips o' 1" maskin' tape around t' NC t' seal off t' holes. Now for t' epoxy or fiberglass resin. Aye aye! Mix up 3 ounces o' resin. Ahoy! Well, blow me down! Pour a small amount down into t' tip and swirl it around t' completely wet t' tip area and fill all t' little holes. Blimey! Begad! Now, arrr, mix chopped carbon fibers (wood fibers/sawdust/chips will work too) into t' remainder o' t' resin and pour it into t' NC. Take your eyebolt and run a nut down on t' small washer about 1/2 t' way t' t' eye. Ya scallywag! Drop it into t' resin and secure it straight up and down. Ya scallywag! Avast! Some paper lightly formed around it will do. Aye aye! This is where t' shock cord will attach with a quick-link.

Finished Rocket



LAUNCH REPORT:

Wednesday, November 18th, shiver me timbers, me hearties, arrr, 1998
Snohomish River Valley, Everett, me bucko, WA
55 degrees f, shiver me timbers, matey, gentle southerly breeze o' 5 knots
Noonish

T' weather was goin' t' cooperate and Eric had only a half day o' school. Ya scallywag! He assembled t' RMS G64-4 while I loaded t' truck and we were off. Well, blow me down! T' rocket sat on t' pad for a minute while we cleared an airplane and then it was off with a roar. Perfect boost with no weather cock t' about 800 feet. T' 4 sec delay was right on as t' chute was expelled just as t' rocket reached apogee and tipped over t' horizontal. Begad! It came down as expected with t' nose cone touchin' down first in t' soft dirt. Well, blow me down! It landed squarely on t' base so t' fins are nay goin' t' be prone t' damage. Avast, me proud beauty! It's just beggin' for=more power. I've got a couple o' I211's t' use and we will if t' weather holds for our waivered launch in Monroe in a few weeks.