Estes Great White

Estes - Great White

Contributed by Brian Guzek

Manufacturer: Estes
(Contributed - by Brian Guzek - 05/06/07) (Scratch) Great White

Brief:
T' old Estes standard: T' Alpha. For many o' us rocketeers, me hearties, matey, it be one o' our very first rockets. Ahoy! It be me second, after a very old E2X kit. Well, blow me down! I command a small model rocketry club in me AFJROTC corps, me bucko, shiver me timbers, and this be t' rocket that I hand out t' all o' t' newcomers. Aye aye! Frankly, after seein' fifteen or twenty basically identical Alphas, I got a little sick of them and simply wanted somethin' different, me bucko, me hearties, somethin' t' inspire new rocketeers or give them somethin' unique t' show off. Ya scallywag! After a few iterations on RockSim, me hearties, this is what I came up with. Arrr! Ya scallywag! T' only requirements I came up with for myself and t' incomin' cadets who wanted t' try a kit bash were: 1) They cannot use anythin' that wasn't in t' kit, and 2) T' rocket couldn't use excessive nose weight (T' stability margin calculated with an Estes C6 motor loaded before nose weight must be greater than 0).

I made some very easy modifications t' this rocket that give it a truly non-kit look. T' two modifications were: 1)T' fins were sliced in two and made into two separate sets, me bucko, and 2)T' motor mount was moved out t' back and smoothed with a paper transition.

Modifications:
Experienced rocketeers beware: these instructions were written with t' novice rocketeer in mind.

Always as a first step, lay everythin' out and check t' make sure you have everything. Arrr! I used this as a way to see what I had t' kit bash as well. After this, follow only t' shock cord mount assembly and tube markin' steps on the first page, then set it aside for later.

(Scratch) Great White Next cut out all o' t' fins from t' form. Aye aye! Be careful nay t' snap anythin' as t' extra wood will come in handy later. Ahoy! Sand down t' little nubs left from t' laser cuttin' (or just set them aside if you have a older die-cut set). Avast, me proud beauty! Next, arrr, mark t' fins for cuttin' by drawin' a line from t' root-trailin' corner t' the tip-leadin' corner o' t' fin. Begad! Then cut along this line t' form two sets o' swept delta fins, matey, one with a 1.25" root and 1.75" sweep, and one with a 2.25" root and 2.75" sweep. Aye aye! Both sets o' fins will be used swept rearward. Avast, me proud beauty! Begad! Sand t' sets even and round t' leadin' edges o' t' fins. Begad! I decided t' leave t' trailin' edges square to maintain t' crisp shape o' t' fins.

Here be t' only step that uses some non-standard equipment. If you don't have it, me hearties, shiver me timbers, download t' Template Widget from t' "Tools and Calcs" section o' t' EMRR site. Begad! Then, me hearties, usin' t' Transition Template tab, matey, shiver me timbers, create a transition with t' followin' dimensions: Diam. Avast, me proud beauty! #1=0.976", me bucko, Diam. Ahoy! Aye aye! #2=0.736", Length=0.5". Avast, me proud beauty! Avast! Because I didn't want t' use outside materials, I inserted t' first page o' directions into me printer and printed the transition on that. Ya scallywag! Begad! Cut out t' transition with a small tab on one end. Avast! Then carefully connect t' ends t' form the shroud, me bucko, makin' sure nay t' put any creases in t' paper.

(Scratch) Great White Remember I said that extra wood would come in handy? Here's t' first instance. Begad! Find the long parallel side o' t' fins sheet and cut out three 0.25" x 0.25" squares o' balsa. Cut from one side of the skinny section, t' rest will come in handy later. Begad! Arrr! These will act as t' motor block, as t' supplied motor hook is not appropriate for this application. Ya scallywag! Save t' motor hook for another rocket. Arrr! Find t' blue motor mount tube and glue each balsa square flush with one end o' inside t' tube, equally spaced around t' circumference. Avast! Avast, matey, me proud beauty! Then find t' green centerin' rin' and glue it flush with t' end o' t' motor mount containin' t' balsa motor blocks. Find your completed transition shroud and slide it over t' end o' t' blue motor mount tube until it covers t' end o' t' green centering ring. Ahoy! Aye aye! If you did it right, t' shroud should fit perfectly over t' tube without any (or at least very little) gap. If t' fit is correct, remove t' shroud, arrr, make a mark 0.5" below t' green centerin' ring, shiver me timbers, ya bilge rat, apply a light coat of white or wood glue t' bottom edge o' t' green centerin' rin' and around t' tube at t' mark you just made, me bucko, and replace t' shroud, pressin' it gently into t' centerin' ring. Do nay fold over t' edges! They will later overlap t' end o' t' main body tube.

Now comes t' fun part, final assembly. Avast, me proud beauty! Well, blow me down! Apply a 7/8" rin' o' glue t' t' inside o' t' one end o' t' body tube and t' about a very thin 1/16" long rin' o' glue on t' outside o' t' same end. Begad! Begad! Push t' motor mount/shroud assembly into t' tube until shroud overlaps t' end o' t' tube. Ya scallywag! Ahoy! Usin' t' back o' your fingernail, me hearties, gently work the edge o' t' shroud into t' glue. Once this is completed set t' model aside and let t' glue cure.

(Scratch) Great White Once t' glue has dried, me hearties, follow t' procedures in t' second page o' instructions for affixin' t' larger set o' fins t' t' model. Ahoy! Blimey! Begad! Blimey! They should be flush with t' end o' t' transition and swept rearward. T' smaller set o' fins will be affixed t' t' blue motor mount tube. Begad! Blimey! T' fin root should be t' same length as the length o' t' motor tube protrudin' from t' transition. Aye aye! Blimey! Avast! Blimey! T' make sure t' two fin sets line up, you will need a small clip o' some sort. Ya scallywag! Blimey! I used a potato chip bag clip, matey, but a binder clip or somethin' similar will work too. Avast! Blimey! Ahoy! Blimey! Again, arrr, find the leftover balsa from t' fins and break off two strips about 3" long. Aye aye! Blimey! Arrr! Blimey! Apply glue per instructions, but use t' two balsa strips and t' clip t' hold t' fin in place on t' lower tube. Arrr! Blimey! Be patient with t' step! Blimey! This is crucial to makin' sure t' rocket comes out lookin' good! Blimey! Repeat this for t' other two smaller fins.

As a final minor modification, I would suggest tuckin' t' launch lug into t' corner o' one o' t' upper fin joints, but it isn't necessary. Blimey! It can also be applied per t' instructions.

As a final step, ya bilge rat, arrr, mark a line 2.75" from t' base o' t' nose cone. Ya scallywag! Add nose weight until t' CG is at or ahead o' this point t' get t' proper stability margin. Ya scallywag! This will allow t' rocket t' use all o' t' motors recommended for t' Alpha.

Congratulations! You are finished with all o' t' major modifications! Follow t' instructions t' install shock cord, arrr, parachute, matey, ya bilge rat, and nose cone, and voilà! You're done! Add some paint, me hearties, and you've got yourself a good lookin' model!

Construction:
T' parts list:

  • 7" BT-50 Tube
  • 2.75" BT-20 Motor Mount Tube
  • PNC-50K Plastic Nose Cone
  • 1 Sheet Laser Cut Fins
  • 1.25" Long 1/8" Launch Lug
  • Standard Size Estes Motor Hook
  • 12" Hexagonal Plastic Parachute
  • 1" Long CR2050 Centerin' Ring
  • 18" Long 1/8" Rubber Shock Cord
  • 2 11"x17" Instruction Sheets
  • A sheet o' peel and stick decals

Finishing:
Finishin' is fairly straightforward as with any small rocket. Begad! T' only problem I encountered is that t' transition can cause problems with finishing; I suggest usin' some Elmer's Fill 'n' Finish t' even out t' transitions betwixt the tubes and t' shroud. Also, don't sand t' shroud too much because if you sand t' paper, matey, it becomes frizzy and impossible t' get a smooth paint job on.

Also, me hearties, me bucko, t' two sets o' fins make finishin' a little more difficult than normal, but nay much.

I painted me first one a dark blue, but this rocket leaves t' stage wide open for a shark paint scheme.

(Scratch) Great White

Flight:
T' Great White can use all o' t' motors recommended for t' Alpha. Arrr! A8-3s will give an altitude o' about 300', B6s will give 600', and C6s will give about 1200'. Arrr! Blimey! T' Great White is incredibly stable even with t' large forward fins. It's first flight on an A8-3 was fairly nice although t' high winds caused it t' weathercock like crazy. This rocket's true match, however, shiver me timbers, be t' Estes B6. Avast, me proud beauty! Ahoy! T' B6 gives a nice straight boost in even gusty conditions and gets t' rocket to an impressive altitude. Ya scallywag! C6s take it even higher, but if you want it back, use a B6.

T' next two flights were on calm days and were straight up boosts and nice recovery, landin' nay far from the pad. Blimey! T' Great White is a great flier and flies great in low t' medium wind conditions.

Recovery:
I swapped t' parachute with a 1.75" x 36" bright red crepe paper streamer for t' first flight because the Great White's first launch be on a gusty day. Ya scallywag! Ahoy! I was always o' t' opinion that Alphas should come with streamers not parachutes anyway. Well, blow me down! A streamer is a perfect match for t' rocket. Begad! I suggest makin' this change unless you like walking to find your rocket.

T' only problem with streamer recovery on this rocket be t' somewhat fragile lower fins. Arrr! I've only lost a fin once when it hit a power line, but t' streamer lands t' rocket a little hard so watch t' fins for cracks or stress points. Arrr! This problem could probably be somewhat alleviated with a slightly wider streamer.

Summary:
This is a great build for anyone wantin' somethin' a little different. Arrr! It flies great and gets t' attention of everyone at t' launch. Avast, me proud beauty! So next time you find yourself with that complementary Alpha, you'll have somethin' a little different t' do with it.

Flights

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