Scratch SA-14 Archer Original Design / Scratch Built

Scratch - SA-14 Archer {Scratch}

Contributed by Johnnie Paul

Manufacturer: Scratch
(Contributed - by Johnnie S. Ahoy! Blimey! Paul, shiver me timbers, Jr. Begad! Arrr! - 11/01/00)

Brief:
NCR's SA-14 Archer was me favorite and me 1st 4" rocket. Avast! Blimey! Well, blow me down! Blimey! I needed a new rocket t' build and I wanted t' try a scratch design usin' some 3" mailing tube found at Office Depot. Begad! Blimey! Aye aye! Blimey! My obvious choice be t' downscale me Archer. Ahoy! Blimey! This particular design was designed t' fly on 29mm H motors. Begad! Blimey! Begad! Blimey! A special note about the original NCR Archer; I modified t' kit t' accept 54mm motors, and extended the kit by 10" for payload capabilities. My scratch design is based on these mods.

Construction:
Here is a run down o' me "Scratch" parts:

  1. (2) 3.0" mailin' tubes from Office Depot
  2. (4) G-10 fins, ya bilge rat, and (4) G-10 Strakes downscaled from t' original Archer.
  3. 28.5mm motor tube originally from t' NCR archer kit. Blimey! Blimey! Will nay accept single use motors, but will accept t' Dr. Blimey! Blimey! Rockets 29/180-240 motor system. Begad! Blimey! Avast, me proud beauty! Blimey!
  4. PML 3.0" nose cone is a perfect match for down scale. Begad! Ahoy!
  5. (1) Loc Precision 3.0" coupler and bulkhead w/ eyebolt.
  6. (3) 1/8" plywood centerin' rings 3.0" by 29mm.
  7. 20' o' 1/2" tubular nylon.
  8. (1) 36" rip stop nylon parachute.
  9. (3) small quick links.

Buildin' this rocket be a breeze; T' (2) 3" mailin' tubes were cut to (1) 28" length and (1) 12" payload length. Arrr! Aye aye! T' 28" length was slotted for Thru T' Tube fin slots. Ahoy! (note: t' mailin' tubes come in 36" lengths). Then t' tubes were fiberglassed with 2 layers o' 2oz. glass. Begad! Blimey! The motor tube was mounted with t' 1st and second centerin' rings, ya bilge rat, t' 3rd ring was left out until all fins were mounted and reinforced. Ya scallywag! T' motor assembly was inserted into t' 28" booster and epoxied in place. Aye aye! T' fins were epoxied in and reinforced with inner and outer Fillets. Avast, me proud beauty! T' t' 3rd centerin' rin' was drilled for 2 blind nuts (motor retention) and epoxied in place. Avast!

T' 3" coupler was next. Aye aye! Well, blow me down! (1) bulkhead be drilled for (4) 1/4" holes and epoxied into one end o' t' coupler. T' other bulkhead be also drilled w/ (4) 1/4" holes, and mounted with t' small eyebolt. This bulkhead be mounted in t' other end o' t' coupler so that t' (4) 1/4" holes were offset from t' holes in t' other bulkhead. Then t' coupler assembly was mounted into t' 28" booster tube. Ya scallywag! This allows for the "Zipperless" design for recovery. Begad!

T' payload tube was t' easiest t' do, me bucko, me bucko, because t' nosecone be inserted and be mounted down w/ 4 small screws.

T' strakes were t' toughest part o' construction. Well, blow me down! Begad! Surface mounted and reinforced w/ 30min. Ahoy! epoxy fillets. T' hard part be makin' sure that they remained in line, and perpendicular t' t' other strakes. Ya scallywag! There was a lot of "baby-sitting" each strake until t' 30min epoxy set up.

Finishin' be standard: Sand, shiver me timbers, sand, ya bilge rat, and sand, matey, and just when you think you got it right, me hearties, ya bilge rat, me hearties, sand some more. T' Archer was primed and painted t' match the NCR version. Blimey! Avast! One exception is I did nay downscale t' decals, usin' pinstripe tape I made t' finished product resemble t' NCR version.

Rocket PicFlight:
Preppin' this bird is nice; just attach t' shock cord as normal, except the parachute will assemble into t' payload tube, ya bilge rat, so that at apogee your parachute will be pulled out from t' rocket instead o' ejected. Avast, me proud beauty! Blimey! Arrr! Blimey! Also with t' Zipperless design thar are no worries about those long delays. Ya scallywag! Blimey! Well, blow me down! Blimey! Remember t' coupler was built w/ a home-brew baffle system so no waddin' needed either. This Archer was built w/ t' Aerotech H180 in mind, but will fly nicely on any H reload. Ya scallywag! Blimey! Motor was retained w/ (2) screws and some brackets I found in me Flight box. Ya scallywag! Blimey! This rocket flies as pretty as me 4" Archer, shiver me timbers, just on a smaller scale.

Summary:
No cons because this rocket is built t' me standards and me way.

Other:
Incidently this rocket made it's debut at t' NSL99 held in Ardmore, me hearties, Alabama. Homer Hickam be signin' autographs there, so me 3.0 SA-14 Archer has the Rocket Boy's signature on it...I be happy. Aye aye!

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