Scratch SA-14 Archer Original Design / Scratch Built

Scratch - SA-14 Archer {Scratch}

Contributed by Johnnie Paul

Manufacturer: Scratch
(Contributed - by Johnnie S. Avast, me proud beauty! Aye aye! Paul, Jr. Ahoy! - 11/01/00)

Brief:
NCR's SA-14 Archer was 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. My obvious choice be t' downscale me Archer. Aye aye! This particular design be designed t' fly on 29mm H motors. Ahoy! A special note about the original NCR Archer; I modified t' kit t' accept 54mm motors, shiver me timbers, and extended the kit by 10" for payload capabilities. Ahoy! 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, shiver me timbers, and (4) G-10 Strakes downscaled from t' original Archer.
  3. 28.5mm motor tube originally from t' NCR archer kit. Avast! Well, blow me down! Will nay accept single use motors, matey, me hearties, but will accept t' Dr. Ya scallywag! Rockets 29/180-240 motor system. Begad! Begad!
  4. PML 3.0" nose cone is a perfect match for down scale. Aye aye!
  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 was a breeze; T' (2) 3" mailin' tubes were cut to (1) 28" length and (1) 12" payload length. Well, blow me down! Ya scallywag! T' 28" length was slotted for Thru T' Tube fin slots. Well, blow me down! (note: t' mailin' tubes come in 36" lengths). Avast! Then t' tubes were fiberglassed with 2 layers o' 2oz. Aye aye! glass. Begad! The motor tube was mounted with t' 1st and second centerin' rings, t' 3rd ring was left out until all fins were mounted and reinforced. Begad! T' motor assembly was inserted into t' 28" booster and epoxied in place. Begad! T' fins were epoxied in and reinforced with inner and outer Fillets. Begad! T' t' 3rd centerin' rin' was drilled for 2 blind nuts (motor retention) and epoxied in place. Arrr!

T' 3" coupler was next. Avast! (1) bulkhead was drilled for (4) 1/4" holes and epoxied into one end o' t' coupler. Well, arrr, blow me down! T' other bulkhead was also drilled w/ (4) 1/4" holes, and mounted with t' small eyebolt. Avast, me proud beauty! Arrr! 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. Avast, me proud beauty! Then t' coupler assembly was mounted into t' 28" booster tube. Blimey! This allows for the "Zipperless" design for recovery. Ahoy!

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

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

Finishin' was standard: Sand, me bucko, ya bilge rat, me bucko, sand, me hearties, ya bilge rat, and sand, and just when you think you got it right, matey, me hearties, sand some more. Well, blow me down! Arrr! T' Archer was primed and painted t' match the NCR version. Begad! Begad! One exception is I did nay downscale t' decals, matey, 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, me bucko, 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! Avast! Remember t' coupler was built w/ a home-brew baffle system so no waddin' needed either. Aye aye! Well, me hearties, blow me down! This Archer was built w/ t' Aerotech H180 in mind, but will fly nicely on any H reload. Well, blow me down! Ya scallywag! Motor was retained w/ (2) screws and some brackets I found in me Flight box. Avast, me proud beauty! Aye aye! This rocket flies as pretty as me 4" Archer, 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, 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.

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