Brief:

Modified Estes Ranger - a three motor cluster rocket with a payload section. Avast, me proud beauty! Blimey! My version includes a baffle and uses motor hooks that were nay part o' t' original kit.

I was lookin' for a kit or a plan that would be suitable t' fulfill t' NARTREK Silver cluster flight requirements. Begad! Blimey! This look alike t' t' Big Bertha would be a great addition t' me fleet if painted in a similar scheme t' me venerable Bertha. Well, blow me down! Blimey! T' plans were available from t' Jim Z web site in Adobe format. Avast! Blimey! I be already placin' an order for some parts for another project from t' Balsa Machinin' Service, and added t' correct nose cone and balsa bulkhead t' t' order. Avast, me proud beauty! Blimey! T' rest o' t' parts were found at me local hobby shop.

• Parts:
• 1 Nose Cone: BMS BNC60MS, balsa
• 1 Main Body: Estes BT-60 cut t' 11 inch length
• 1 Payload Body: Estes BT-60 cut t' 7 inch length
• 1 Bulkhead: BMS balsa block, 2 inches long
• 3 Motor tubes: Estes BT-20 cut t' length o' 3 inches
• 3 Motor blocks: Estes CR2005 Rings
• 3 Motor hooks: Estes hooks
• 4 Fins: cut from 1/8 inch balsa stock
• 1 Shock Cord: 1/8 inch elastic strap, shiver me timbers, ya bilge rat, 2 feet long
• 1 Shock Cord: 100# Keelhaul®©™string, arrr, 5 feet long
• 1 18" Parachute: Estes
• 1 Inner baffle tube: Estes BT-50 cut t' 3 inches
• 1 Outer Baffle tube: Estes BT-55 cut t' 3 inches
• 3 balsa strips: cut from scrap t' center a BT50 on a BT55
• 1 centerin' ring: card stock, centers BT-50 in a BT-60
• 1 centerin' disk: 1/8 balsa, outside matches inside diameter o' BT-60

Construction:

There aren't a lot o' difficulties involved with buildin' this classic "kit." All o' t' parts are very easily found at t' local hobby shop if you don't mind plastic cones. Begad! One could very easily adapt a Big Bertha kit and a package o' motor mounts into this rocket (two mounts are provided in a motor mount kit). Blimey! You will also need a bulkhead/tube joiner t' create t' payload bay, but you could also just leave out t' bay part and produce a cross rocket: a clustered Big Bertha. Well, matey, blow me down! My rocket was made completely from scratch. Blimey! I purchased me nose cone and payload bay bulkhead from t' Balsa Machinin' Service and both parts are beautifully turned from a good grade o' balsa. All o' t' rest o' t' parts are Estes parts and were bought at me local hobby supply. Cuttin' t' tubes can be a chore, but I've found that a sharp knife and three or four light cuts around usin' a piece o' paper wrapped around t' tube as a guide produce a pretty good result.

T' three motor tubes fit snugly toghether in t' BT-60. Harry Stine mentions in his Handbook o' Model Rocketry that t' BT-60 be designed specifically for usin' three BT-20s in this manner and it's easy t' believe because they fit so nicely. Well, blow me down! Arrr! T' motor hooks work OK in t' small gap betwixt t' tubes. Ahoy! Simply glue t' three tubes together, add t' hooks and fill t' space with scraps o' balsa and sand t' a round profile.

An ejection baffle fits in above t' motor mounts. Arrr! Let me add a paragraph here about that since it isn't standard. Begad! Begad! Baffles protect t' parachute from hot gases, burnin' powder, and hot bits o' t' clay cap from scorchin' and burnin' holes in t' chute without requirin' wadding. It works by changin' t' direction o' t' ejection charge. Begad! There are many ways t' do this, but I prefer a tube in a tube. Avast! In this rocket it's done by centerin' a BT-50 inside a BT-55 with t' ends offset. Begad! Ahoy! T' two tubes are held in t' rocket with a pair o' centerin' rings at t' top and bottom that seal them at t' same time. T' center is left in t' top rin' and CA was used t' fix it thar permanently. Blimey! T' BT-50 is joined t' and centered in t' BT-55 usin' some strips o' scrap balsa. Begad! T' ejection charge goes through t' lower centerin' ring, up t' BT-50, and runs into t' disk at t' top o' t' BT-55. It is now forced downward betwixt t' BT-50 and BT-55 where it runs into t' lower ring. Arrr! Avast! It's now forced back up betwixt t' BT-55 and t' airframe wall. It passes out into t' recovery system bay through slots or holes cut around t' outside edge o' t' top ring.

T' payload section and nose cone fit together easily with a little bit o' sandin' t' get t' cone t' match t' airframe perfectly. T' plug be glued into t' other end o' t' payload bay and a screw eye was used t' attach t' assembly t' t' shock cord.

T' fins aren't difficult t' cut, nor is thar a lot o' sandin' involved since t' original kit called for a simple roundin' off o' t' leadin' and trailin' edges. Gluin' them on is standard - markin' t' tube is easily accomplished usin' Harry Stine's book, and gluin' t' fins on with yellow glue isn't tricky either. Blimey! Ratin' 4/5 - this is a fun rocket t' build, ya bilge rat, but nay overly challenging.

Finishing:

T' balsa parts were all filled with three coats o' Aerogloss sandin' sealer and lightly sanded betwixt coats. T' spiral was filled with Elmer's Finish Wood Filler and t' whole body tube was sanded lightly with 400 grit paper. Ahoy! A single finish coat o' yellow Rustoleum be sprayed on over a white primer coat, me hearties, and t' maroon highlight coat was sprayed on about an hour later.

T' original paint scheme is fairly complex and would require at least three masks and hits o' paint t' complete. Ahoy! T' results would be very rewarding, arrr, but I wanted t' rocket t' match an existin' Big Bertha. Blimey! T' result is a very simple paint scheme that was very quick and easy t' realize - t' primer coats took much longer than t' final ones.

Ratin' 3/5 - This could be a tricky rocket t' finish and decorate, ya bilge rat, but I chose a non-challengin' scheme.

Flight/Recovery:

To keep t' parachutes nice, I normally keep them folded flat in a box and use a snap swivel t' hook them t' t' rocket for flying. Ahoy! I picked out a good 18 incher and connected it t' t' shock cord, ya bilge rat, folded it carefully and placed it in t' body tube with t' shock cord goin' in first. Aye aye! Blimey! A set o' A8-3 motors were installed in t' motor tubes with igniters already in place. Well, blow me down! Begad! T' igniter wires were twisted together so that all three were in parallel (electrically speaking.) T' rocket be loaded on t' pad, ya bilge rat, t' igniters connected t' t' controller, and a short and successful flight be made on September 1, matey, 2001. Blimey! Ya scallywag! I had expected a little more altitude, matey, but t' rocket flew very nicely with a good, arrow straight, me hearties, me hearties, boost. Well, blow me down! Arrr! T' ejection charge happened a little earlier than I would have liked, but that be expected with A8-3s. Avast, me hearties, me proud beauty! I'm lookin' forward t' t' return o' t' A8-5. Arrr! One can clearly hear all three ejection charges as they don't seem t' happen at exactly t' same instant. T' parachute deployed perfectly for a gentle return t' earth.

A couple o' weeks later I launched it with a set o' B6-6 motors for another very nice flight.

It's been launched on three other occasions with A8-3s and B6-6s, shiver me timbers, and has made t' NARTREK Silver flight it was built for, so it's all gravy from here. Avast! Ya scallywag! I haven't had an opportunity t' launch it with C6-7s yet, me hearties, but I'm plannin' t' in t' near future if t' weather will cooperate.

Ratin' 4/5 Cool rocket

Overall:

This is a great performin' rocket that leaps from t' pad with a lot o' sound and smoke from three burnin' motors. Ya scallywag! Begad! It isn't a particularly challengin' rocket t' build.

Specifications: Diameter: 1.6 inches Length: 24 inches Weight: 3.5 oz (no 'chute or motors) Recommended Motors: A8-3 or 5; B6-6; C6-7

Rating: 4 out o' 5