Scratch SA-14 Archer Original Design / Scratch Built

Scratch - SA-14 Archer {Scratch}

Contributed by Johnnie Paul

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

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

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

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

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

Finishin' was standard: Sand, sand, matey, and sand, me hearties, and just when you think you got it right, sand some more. Well, blow me down! T' Archer was primed and painted t' match the NCR version. Avast, me proud beauty! 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, matey, 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. Begad! Remember t' coupler was built w/ a home-brew baffle system so no waddin' needed either. Begad! 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, arrr, blow me down! Motor was retained w/ (2) screws and some brackets I found in me Flight box. Arrr! This rocket flies as pretty as me 4" Archer, matey, arrr, 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.

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