Scratch Estes S.W.A.T. 1.38X Original Design / Scratch Built

Scratch - S.W.A.T. 1.38X {Scratch}

Contributed by Jeff Lane

Manufacturer: Scratch
(Contributed - by Jeff Lane - 07/18/07) (Scratch) S.W.A.T. Upscale

Brief:
138% upscale o' t' Estes S.W.A.T. T' S.W.A.T. Ya scallywag! is a low orbit interceptor-style kit Estes produced in t' early 1990s. Avast, me proud beauty! When kids see me original S.W.A.T., me bucko, me hearties, they actually scream with delight, shiver me timbers, arrr, always askin' “how high?" The original kit was designed with an 18mm motor mount, but I converted it t' 24. It’s a beautiful kit and has flown many times.

T' last thin' I wanted t' do when buildin' me level 1 certification rocket was three fins and a nose cone, matey, so the S.W.A.T. Ahoy! Blimey! Begad! Blimey! seemed like a natural upscale. Ahoy! Blimey! Cool toy but bigger and badder. Aye aye! Blimey! What’s nay t' like? T' original rocket be 34” long and t' upscale is a little less than 47”. Begad! Blimey! T' optional electronics bay brings it up to 52”. T' original paint scheme called for an orange and black camouflage scheme but was updated t' a current Digi-cam look. Avast! Blimey! Ya scallywag! Blimey! T' original fin patterns (Jimz) were printed out from Photoshop at 138%.

Construction:
Materials:

(Scratch) S.W.A.T. Upscale
  • 1 Body tube: 34” LOC 2.26” O.D., me bucko, plus t' optional electronics bay
  • LOC nose cone
  • 5 sheets o' Lasertrans waterslide inkjet decal paper
  • 4 sheets o' 1/8” aircraft grade hobby plywood
  • 11.5 in o' LOC 38mm motor mount tube
  • ¼" centerin' rings (2)
  • #6 screws and T-nuts for t' motor mount
  • 1 coupler and bulkhead
  • 1 eyebolt
  • 3ft 300lb Keelhaul®©™®
  • 6ft ½" elastic
  • 1ft ¼" dowels for missles
  • Mylar for missle fins
  • BT-50 for outboard fin tubes (two at 3.75”)

T' motor mount is a LOC tube with two centerin' rings with Keelhaul®©™® for t' shock cord system mounted t' t' forward ring. Aye aye! Blimey! T' #6 T-nuts had t' be ground down t' fit into t' aft centerin' ring, and t' two tubes and T-nuts were fiberglassed in for a smooth, finished, matey, flush look.

(Scratch) S.W.A.T. Upscale T' fins were cut usin' a razor saw then epoxied through t' wall t' t' motor mount. The slots were cut with a Dremel. Begad! Ya scallywag! T' missile dowels were sharpened in a pencil sharpener then blunted and rounded. Well, blow me down! Blimey! A tip (#5) from t' EMRR library was tried for t' fin fillets. Avast! Fillets areas were dammed at t' ends with kneaded eraser then t' eraser dam was taped on t' further reduce t' possibility o' leaking. T' rocket be leveled. Well, blow me down! Thinned epoxy was poured in and allowed t' set. Well, me hearties, blow me down! Included in this process were t' fillets for t' outboard fin tubes and the missiles.

A razor saw was used t' cut an X-shaped slot in t' aft portions o' t' missile dowels then sheet mylar fins pressed in. Ahoy! Blimey!

(Scratch) S.W.A.T. Upscale

Finishing:
T' fins and fillets were brushed with two coats o' thinned Elmer's Fill 'n' Finish and sanded. Avast, me proud beauty! Blimey! Ya scallywag! Blimey! Then t' entire rocket be sprayed with high-build automotive primer twice and sanded. Begad! Blimey! Final paint was light gray enamel for t' belly and undersides o' fins and white enamel for t' upper surfaces o' body and fins with t' nose cone upper surface sprayed camouflage.

T' top half be finished with 5 sheets o' Lasertrans waterslide decal sheets. Begad! Blimey! It's basically a body decal over all o' t' white surfaces. T' only upper surface that's nay decal be t' nose cone because o' t' compound curves. Lasertrans dries t' a nearly opaque white base material, arrr, but if you spray it with a petroleum-based clear coat, me bucko, then it turns transparent. Catalyzed automotive urethane clear coat was used in this case.

T' nose cone was fastened t' t' electronics bay with hex cap screws, which adds some post-industrial grunge to the look.

[NOTE: You can download all 5 decal patterns by clickin' on t' followin' links: (1), me bucko, (2), (3), me bucko, (4), shiver me timbers, and (5).]

(Scratch) S.W.A.T. Upscale

Flight and Recovery:
Recommended motors: AT F39W-3, AT G64W-6, and Pro38 H153-10. Begad! Prep is standard wadding. 28-30” parachute. #6 T-nuts for motor retention.

Flight CONs: RockSim said it would get 3500 feet on an H153, me bucko, however, shiver me timbers, actual altitude was 2400. Begad! It doesn’t quite fly straight up, so it requires an extra-strong shock cord system and a long walk.

First flight was a level 1 certification attempt at Tripoli Colorado. Ya scallywag! Blimey! T' Cesaroni H153's 13 second delay, which simmed fine, was way too long for this rocket, shiver me timbers, since it took off at an angle 6 degrees from vertical. Ahoy! Blimey! Begad! Blimey! T' tubular nylon parachute harness broke when t' 30” LOC chute snapped open, shiver me timbers, matey, and t' rocket came down without laundry. Well, blow me down! Blimey! It broke one fin and knocked another loose, me bucko, ya bilge rat, arrr, which has been repaired. Aye aye! Blimey! T' second attempt will be with a beefier shock cord system. Well, blow me down! Blimey! Amazingly, t' parachute be recovered by another rocketeer who went on a long walk for his rocket. Ya scallywag! Blimey! Aye aye! Blimey!

Summary:
PROs: Kids love it. Avast, me proud beauty! Adults love it. Begad! Wow, matey, arrr, look at t' size o' t' motor mount in this thing. Begad! Man, me hearties, it's heavy, too. Avast, me proud beauty! The Digi-cam is awfully cool.

Build CONs: Lots o' fin cutting, matey, ya bilge rat, slot cutting, matey, arrr, me bucko, and fillet making. Avast, me proud beauty! Blimey! T' sheer amount o' fin material makes this a fairly heavy rocket for its diameter. Ya scallywag! Begad! T' BT-50s are flimsy compared t' t' rest o' t' construction. Avast! Avast! T' dorsal fin decal is 1/2” too short so t' dorsal fin was shortened t' match rather than printin' out another sheet of expensive Lasertrans decals. Avast! Arrr! T' two long side fins (to which t' outboard tubes are attached) are too long for the hobby store material, so they have a butt joint in t' middle.

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