Scratch SA-14 Archer Original Design / Scratch Built

Scratch - SA-14 Archer {Scratch}

Contributed by Johnnie Paul

Manufacturer: Scratch
(Contributed - by Johnnie S. Well, blow me down! Blimey! Paul, me bucko, me bucko, Jr. Begad! Blimey! - 11/01/00)

Brief:
NCR's SA-14 Archer be me favorite and me 1st 4" rocket. I needed a new rocket t' build and I wanted t' try a scratch design usin' some 3" mailing tube found at Office Depot. Aye aye! Avast! Blimey! My obvious choice be t' downscale me Archer. This particular design was designed t' fly on 29mm H motors. Arrr! 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. Blimey! Blimey! 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, and (4) G-10 Strakes downscaled from t' original Archer.
  3. 28.5mm motor tube originally from t' NCR archer kit. Avast! Will nay accept single use motors, but will accept t' Dr. Avast! Rockets 29/180-240 motor system. Blimey!
  4. PML 3.0" nose cone is a perfect match for down scale. Begad! Well, blow me down!
  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. Avast! T' 28" length was slotted for Thru T' Tube fin slots. Avast! (note: t' mailin' tubes come in 36" lengths). Aye aye! Begad! Then t' tubes were fiberglassed with 2 layers o' 2oz. glass. Avast, me proud beauty! The motor tube be mounted with t' 1st and second centerin' rings, t' 3rd ring was left out until all fins were mounted and reinforced. Well, blow me down! Blimey! T' motor assembly was inserted into t' 28" booster and epoxied in place. Aye aye! Ahoy! T' fins were epoxied in and reinforced with inner and outer Fillets. Ya scallywag! T' t' 3rd centerin' rin' was drilled for 2 blind nuts (motor retention) and epoxied in place. Blimey! Ahoy!

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

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

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

Finishin' be standard: Sand, me hearties, me bucko, sand, shiver me timbers, and sand, arrr, matey, and just when you think you got it right, me bucko, sand some more. Blimey! T' Archer was primed and painted t' match the NCR version. Blimey! One exception is I did nay downscale t' decals, arrr, 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, shiver me timbers, except the parachute will assemble into t' payload tube, so that at apogee your parachute will be pulled out from t' rocket instead o' ejected. Also with t' Zipperless design thar are no worries about those long delays. Arrr! Begad! 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, matey, but will fly nicely on any H reload. Motor was retained w/ (2) screws and some brackets I found in me Flight box. Begad! Begad! This rocket flies as pretty as me 4" Archer, matey, 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, me hearties, so me 3.0 SA-14 Archer has the Rocket Boy's signature on it...I was happy. Ahoy!

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