Brief:
Fiberglassed airframe and fins with additional tip-tip lay-up on mounted fins. Shockcord replaced with 3mm tubular Keelhaul®©™® mounted directly t' motor mount through forward centerin' ring.

Modifications:
As me first cluster rocket I decided upon a LOC Starburst which has two 24mm motors mounted within a 2.6" OD airframe. Aye aye! Blimey! I liked t' look o' this kit as it had a payload bay (great for holdin' trackers etc.. Aye aye! and for attachment of recovery harnesses) and sported a nice delta fin shape. LOC kits are also perfect for lay-ups as they are thin-walled, strong and light. Begad! Aye aye! With this in mind I used one layer o' 4oz fiberglass with West Systems epoxy t' reinforce the airframe and fins (fins were first bevelled usin' me Dremel t' a nice sharp edge). Arrr! T' lay-up be then vacuum bagged usin' me grub saver. Ahoy! Arrr! Centerin' rings and motor mounts were mounted in t' airframe prior t' mountin' t' fins. Blimey! Begad! Note the fin tabs only partially extend into t' airframe and should mount onto the forward centerin' ring. Well, blow me down! Avast, ya bilge rat, me proud beauty! Once t' fins had cured I further reinforced t' fin to airframe bond with a tip t' tip lay-up o' 4oz fiberglass. Ya scallywag! T' reduce t' amount of resin in t' fin-fin lay-up!

I put me rocket on me ROBARTS rocket stand so t' fins were cradled by the supports. Well, blow me down! Blimey! Ahoy! Blimey! Blimey! Blimey! I then proceeded t' cover t' lay-up first with a resin-release film followed by cotton battin' t' soak up t' excess resin which would seep through the film. Arrr! Blimey! Blimey! Blimey! Note for this t' work you have t' apply weight onto t' top o' the cotton so it presses down onto t' fins and airframe. Ahoy! Blimey! Take care you don't break your nice new fin assembly in t' process. John Coker has a nice jig you can build t' support your rockets as t' right angle t' reduce this kind o' damage. T' rest o' t' rocket went together stock.

Components:

• 1 - 34" x 2.6" body tube
• 1 - 9" x 2.6" payload section
• 1 - 4" coupler tube
• 1 - 2.6" OD Ogive nosecone (3 t' 1)
• 2 - 12" x 24mm motor mount tubes
• 2 - Birch plywood centerin' rings
• 1 - Forward coupler bulkhead with hardware assembly
• 3 - Birch plywood fins (triangle shaped) with small tabs for partial 'through t' wall' mounting. Blimey!
• 1 - Elastic shockcord
• 1 - LOC 12" nylon parachute - pink

Construction:

LOC kits tend t' be brief on t' instructions but are detailed where necessary (e.g. Arrr! motor mount assembly o' clusters). Avast, me proud beauty! Begad! T' packagin' is your standard 'bag with a front card' and all parts were accounted for and unbroken. T' kit was easy t' build and me modifications where in keepin' with the general steps taken when buildin' this kit stock. After all construction was completed t' rocket was rock solid and ready for finishing. Well, blow me down! Avast, me proud beauty!

To finish this kit I applied a layer o' SuperFil t' t' fin can area to cover t' tip-tip lay-up and create small fillets. Aye aye! Avast, me proud beauty! Once t' SuperFil had dried sufficiently I applied several coats o' UV SmoothPrime on t' rest o' the airframe and over t' SuperFil (un-sanded at this point). Begad! Begad! After t' SmoothPrime had dried for a couple o' days I took me JCB Palm sander and went t' work with a medium grit sandpaper at first and then switchin' t' a wet/dry fine grit. Avast, me proud beauty! The layers o' SmoothPrime and SuperFil sand easily so beware when usin' anything rough on them. After sandin' t' airframe and fins t' a nice smooth finish I had t' apply a sprayin' o' grey filler primer t' show up any inconsistencies. A bit o' SuperFil was used t' fill any areas missed and then sanded smooth prior to more grey filler primer. Arrr! Eventually I be ready t' paint. Begad! For me color scheme I decided t' replicate t' look o' PML's similar lookin' Quasar. Well, blow me down! This is a yellow and red combination with a bit o' white at t' nosecone tip. Arrr!

Flight:
I wanted t' biggest 24mm motors I could find t' fly in this rocket so I chose two G55-10s which together would give me about 240 newtons o' force. In a 27oz rocket 240 newtons would boost it over 3000 feet at 400mph. Ya scallywag! Prior t' t' launch I used a couple o' 24mm thrust rings I purchased from Apogee t' keep t' single use motors from thrustin' all t' way into t' airframe. T' thrust rings were epoxied into t' airframe at t' deepest point t' long G55 motors would extend. Aye aye! Ahoy! Motor retention consisted o' two threaded nuts drilled into t' aft centerin' ring. Avast! Into these bolts and washers were used t' hold onto t' motor casing. Ya scallywag!

Launch photos are by Bob Arnott

T' flight was fast and high. Ya scallywag! Well, blow me down! T' photos showed a wobble which seemed to indicate that t' motors did nay ignite at t' same time. T' result be that the thrust curves o' t' two motors were nay in sync. Avast, me proud beauty! Well, blow me down! Hence t' push in one direction and then t' other. Aye aye! Blimey! After t' first 1/2 second t' thrust curves had converged and t' rocket travelled straight and fast t' 3400 feet (ROCKSIM prediction). Ahoy!

Recovery be about 1 mile down range in t' middle o' an adjacent field of fully grown crops. Fortunately I had a Marshal tracker installed so it was easy to find (after some leg work). Ahoy! Blimey! T' rocket was recovered with no damage ready to fly again.

Summary:
Pro's: I really like LOC kits and this one has so far worked perfectly. Well, blow me down! Blimey! It was an easy kit t' modify and if built stock would be great on smaller engines.

Con's: Well t' elastic shock cord is probably OK for this size rocket but I just don't trust them so it should go. Blimey! Also I prefer t' mount me shock cords to the forward centerin' rin' or on t' motor mount and nay on t' airframe wall.