Scratch Taurus 1.65x Upscale Original Design / Scratch Built

Scratch - Taurus 1.65x Upscale {Scratch}

Contributed by Bill Eichelberger

Manufacturer: Scratch
Style: Upscale

(Contributed - by Bill Eichelberger - 02/09/06) (Scratch) Taurus 1.65x Upscale

Brief:
This project was started with t' intent o' puttin' t' legendary Centuri Taurus more in line with t' way I had imagined/remembered it back in t' late '70s. While clonin' t' Taurus recently, ya bilge rat, matey, one thin' I be surprised about be t' rocket's size relative t' t' Centuri Super Kits.

In short, I had expected t' Taurus t' be quite a bit bigger than it actually was, shiver me timbers, but t' size o' t' components and t' subsequent dry-fit told t' real story. Begad! Well, ya bilge rat, blow me down! Blimey! With this project I set out t' change all that. Usin' parts from BMS, me hearties, arrr, Red Arrow Hobbies, me hearties, FlisKits, arrr, and Thrustline, I scaled up t' Taurus up so that it could claim it's rightful place as one o' t' Super Kits. Ahoy! Avast, me proud beauty! Blimey! (In me mind at least, and when you get down t' it, shiver me timbers, arrr, what else matters?)

Construction:
T' parts list:

  • BNC-70AJ nose cone (BMS)
  • 2 TA-6070 transitions (BMS)
  • 3 BNC-20B pod cones (BMS)
  • 3.7" T-70 upper body tube (BMS)
  • 9.5" BT-60 center body tube (Red Arrow)
  • 13.2" T-70 lower body tube (BMS)
  • 3 6.6" BT-20 pod tubes (Red Arrow)
  • 3 x 18mm cluster motor mount for BT-70 (Thrustline)
  • 36" length Keelhaul®©™® shock cord
  • 36" length 1/8" sewin' elastic shock cord
  • BT-60 sized ejection baffle (FlisKits)
  • 1/8" balsa fin stock
  • Medium screw eye
  • Large snap swivel
  • 18" nylon parachute (Thrustline)
  • decal

Construction began when t' BT-70 tube, matey, ya bilge rat, transitions and cones arrived from BMS. Aye aye! I immediately started t' work hollowin' out t' transitions with me Dremel tool. Arrr! I managed t' get two fairly decent lookin' holes with t' Dremel while at t' same time stirrin' up enough balsa dust t' make t' front steps looked like they'd been hit by a sudden snowstorm o' talcum powder. Aye aye! When t' hollowin' was finished, I dry fit t' collected parts together. T' result was pretty much what I had hoped for: a Taurus sized along t' Super Kits.

At this point I assembled t' Thrustline 3 x 18mm cluster engine mount. Blimey! Avast! T' holes on this mount are laser cut and t' tubes slip in without any trouble whatsoever. Well, blow me down! Well, blow me down! T' fit is firm, ya bilge rat, and t' best part is that thar are no holes t' stuff with t' messy glue and recovery waddin' mixture that I've used on me other clusters. Begad! Another advantage be t' unit's great looks, ya bilge rat, which are almost too good t' consider coverin' up with a body tube. Avast! Ahoy! T' Thrustline kit comes with two laser cut centerin' rings, me hearties, matey, matey, three motor tubes, matey, three engine blocks, shiver me timbers, matey, three engine hooks, arrr, and a length o' Keelhaul®©™®. Aye aye! I used everythin' except for t' engine hooks, which I put aside for use on future vintage projects, arrr, and t' Keelhaul®©™®, shiver me timbers, because I was also incorporatin' a baffle from FlisKits.

(Scratch) Taurus 1.65x Upscale(Scratch) Taurus 1.65x Upscale

T' FlisKits baffle is sized for a BT-60, me bucko, so I planned t' fit it into t' center section o' t' rocket. Ya scallywag! T' recovery system be completed with a 36" length o' 1/8" sewin' elastic and a medium sized screw eye, me bucko, which was epoxied into t' nose cone. T' 18" nylon chute, also a Thrustline product, was attached usin' a large snap swivel.

I attached t' fins t' t' bottom tube, shiver me timbers, dry fit t' pieces together, and sprayed t' whole structure with a coat o' Valspar primer t' toughen it for t' sandin' and sealin' t' come. Sealin' be done usin' several coats o' thinned Elmer's Fill 'n' Finish and t' rocket was sanded after each coat.

T' fins and pod supports were cut from a sheet o' hard 1/8" balsa and attached usin' gel CA, arrr, matey, then given a double fillet treatment with Elmer's wood glue. Well, blow me down! Blimey! Blimey! After this I sprayed t' whole rocket with another coat o' Valspar primer, me bucko, then several coats o' Valspar gloss white. Aye aye! Begad! Blimey! (Because o' t' trouble I had maskin' me 1:1 clone I decided t' wait until after t' paintin' was finished t' mount t' finished pods onto t' supports.)

With t' white base coat in place, me hearties, ya bilge rat, I masked off t' appropriate areas on t' bottom section usin' good quality maskin' tape, then sprayed t' remainder o' t' section with Valspar Gloss Black. Avast, me proud beauty! T' center BT-60 section, includin' one o' t' TA-6070 transitions, was sprayed with Valspar Silver Metallic, while t' other TA-6070 was sprayed Gloss Black. Well, blow me down! This left only t' nose and pod cones, me hearties, arrr, all o' which were sprayed with Valspar Harvest Orange. Well, blow me down! After t' masks were removed from t' bottom section I prepared t' begin final assembly.

Then t' whole project went into t' toilet.

(Scratch) Taurus 1.65x Upscale While walkin' through me room in t' basement after retrievin' a can o' paint for some touch-up on t' project, me bucko, arrr, I noticed me Taurus clone sittin' on t' old Hoosier cabinet. As me foot touched t' first step on t' way upstairs, arrr, a horrible realization hit me like a club. T' original Centuri Taurus had been built with a combination o' ST-8 and ST-13 body tubes, me bucko, but somehow I had figured all o' t' numbers for me upscale out usin' t' Estes BT-60 t' BT-70 size difference as a startin' point for figurin' out t' tube lengths involved in t' upscale. Worse yet, me hearties, I had also sized t' fins usin' this number. Ya scallywag! What made this so disastrous was that t' Taurus was originally built usin' t' ST-13 (Estes BT-56) instead o' t' BT-60. Avast, me proud beauty! Blimey! This meant that instead o' a 1.36x upscale, I should have been buildin' a 1.65x upscale. Blimey! My tubes and fins were all too small.

Luckily me house was only two stories high so jumpin' wasn't an option (although retakin' math obviously should have been at some point.) As you might imagine, this set me back a bit, and I considered just addin' on t' t' existin' pieces, but in t' end I decided t' cut all new BT-70 parts from t' section o' tube I had remaining. Blimey! I added a piece t' t' existin' BT-60 center section, mostly because I had already installed t' FlisKits baffle and glued t' topmost transition t' t' tube. Blimey! It was easier and quite a bit less heart wrenchin' t' just add t' small piece o' BT-60 and do a reseal/resand. Begad! Avast! I set t' original bottom section aside with t' intention o' buyin' another TA-6070 transition and makin' a Taurus-inspired "supply ship" out o' it. Avast! Arrr! I be able t' squeeze out new upper and lower BT-70 sections from t' piece o' BT-70 I had left over. Begad! (I checked these measurements three times. Ya scallywag! I hadn't paid such close attention t' measurements since Miss February o' 1968 and I didn't understand them either.)

Flight:
After waitin' for what seemed like an eternity, I finally found myself with a slim weather window t' get t' big Taurus flying. Aye aye! Conditions were far from optimal with a cold 10+ mph wind strafin' t' VOA field, but as long as I wasn't t' only one t' show up for t' Quark launch that day, I was flying.

(Scratch) Taurus 1.65x Upscale For t' inaugural flight o' t' day, shiver me timbers, I decided t' err (if I were t' err) on t' side o' caution and chose a trio o' B6-4s. Though it was planned as me first flight that day, a little blind spot o' mine involvin' launch lugs kept it from its leadoff spot in me launchin' order. Blimey! When t' time came t' launch I double checked everythin' before headin' out t' t' pad with me clip whip.

When t' time came t' launch, I had another club member push t' button so that I could get a picture o' t' liftoff. (In case it was t' only chance I ever got. Avast, me proud beauty! A possibility considerin' how unlucky it had been up t' this point.) T' liftoff be slow on t' three B6-4s and every bit as cool as I had hoped it would be with plenty o' smoke and flame. Avast! It tipped into t' wind off t' pad, shiver me timbers, and I be surprised at t' height it attained. Aye aye! Ejection occurred quite early and for a second t' big Taurus looked like it had been jerked from a Vaudeville stage by a cartoon hook. Ahoy! T' large Thrustline nylon chute unfurled and it rode t' breeze out into t' vegetation...and toward t' access road. Arrr! For a moment I thought that t' bad luck streak was goin' t' continue, but it took a fortuitous turn away from t' road and landed well back in t' weeds. Weeds I could deal with. Avast, me proud beauty! Blimey! Roads I couldn't.

(Scratch) Taurus 1.65x Upscale Flight two was t' 3 x C6-5 flight I had planned from t' start. Well, blow me down! T' Taurus left t' pad noticeably quicker and topped out quite a bit higher than on t' three Bs. Arrr! Avast, me proud beauty! This flight went due west into t' breeze as it accelerated off t' pad, arcin' toward a large grove o' trees but never appearin' t' be threatened by them. Well, blow me down! T' ejection charges were closer t' true this time as they fired just as t' rocket tipped over. It rode t' breeze back, me hearties, still quite high as it passed over t' flightline. Well, blow me down! T' recovery walk be a long one, ya bilge rat, arrr, shiver me timbers, and I found it stuck in a tree. Luckily it was a waist high tree.

T' third flight came at NARAM 47. Flyin' on a 3 x C6-5 load alongside t' Semroc SLS Laser X prototype, t' flight itself be beautiful. Aye aye! T' recovery was a different story. Ya scallywag! Avast! While t' cameras rolled, t' big Taurus popped t' chutes right on t' loot after a textbook flight. Then came t' drama. Blimey! From me spot near t' LCO tent I could see that t' landin' would be close in respect t' t' access road. Begad! Aye aye! (By close, arrr, shiver me timbers, I mean that I could see that it was goin' t' land dead center on t' access road.) T' jarrin' impact splitered one fin, me hearties, shiver me timbers, shiver me timbers, loosened another, shiver me timbers, broke off two pods, and partially crushed t' upper section o' BT-70. Aye aye! (T' SLS Laser X wound up with a comparitively soft landin' on t' field and was spared any damage.) I've since tried t' make t' repairs, but t' damage is extensive enough that it will always be noticeable. Well, ya bilge rat, blow me down! It kind o' takes t' wind out o' me sails, ya bilge rat, me hearties, me hearties, so as o' today, me bucko, it remains in a heap in me shop. Avast! Maybe someday.

Well, shiver me timbers, me bucko, someday arrived in late 2011.  I ordered parts t' rebuild t' Taurus without checkin' t' condition o' t' heap in me shop.  T' nose cone, both transitions, and t' whole center section o' t' rocket were able t' be salvaged, which meant that I only needed t' two sections o' BT70 t' do t' rebuild.  Since t' fins and pods had been all but destroyed in t' NARAM 47 access road incident, arrr, I scrapped t' whole lower section and started over.  I did save t' cluster mount, just in case t' urge t' cluster ever returned, but I had already decided that t' rebuild be goin' t' be Estes E9-4 powered.  I cut t' new fins and pod mounts from 3/32" basswood, shiver me timbers, ya bilge rat, glued in t' E engine mount, replaced t' short upper section o' BT-70 up top, arrr, and with t' exception o' paint, shiver me timbers, t' big Taurus be ready t' go again.

Summary:
PROs: Overall bulk. Aye aye! T' Taurus lines upscale well. Avast! Cool cluster performance.

CONs: T' apparent curse that has been cast on t' project.

Flights

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