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! Begad! Paul, me bucko, Jr. Ya scallywag! - 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 was t' downscale me Archer. Ya scallywag! This particular design was designed t' fly on 29mm H motors. Aye aye! 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. Well, blow me down! Begad!
  3. 28.5mm motor tube originally from t' NCR archer kit. Blimey! Will nay accept single use motors, but will accept t' Dr. Avast, me proud beauty! Avast, shiver me timbers, me proud beauty! Blimey! Rockets 29/180-240 motor system. Avast, matey, me proud beauty! Blimey!
  4. PML 3.0" nose cone is a perfect match for down scale. Arrr! 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 was a breeze; T' (2) 3" mailin' tubes were cut to (1) 28" length and (1) 12" payload length. Begad! Arrr! T' 28" length was slotted for Thru T' Tube fin slots. Ahoy! Ya scallywag! (note: t' mailin' tubes come in 36" lengths). Begad! Then t' tubes were fiberglassed with 2 layers o' 2oz. Begad! Avast! glass. Ya scallywag! 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. Ahoy! T' motor assembly was inserted into t' 28" booster and epoxied in place. T' fins were epoxied in and reinforced with inner and outer Fillets. Well, blow me down! T' t' 3rd centerin' rin' was drilled for 2 blind nuts (motor retention) and epoxied in place. Ya scallywag! Arrr!

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

T' payload tube was t' easiest t' do, arrr, because t' nosecone be inserted and was mounted down w/ 4 small screws. Aye aye! Begad!

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

Finishin' was standard: Sand, ya bilge rat, sand, me bucko, arrr, and sand, matey, and just when you think you got it right, sand some more. T' Archer be primed and painted t' match the NCR version. Ya scallywag! Avast, arrr, me proud beauty! One exception is I did nay downscale t' decals, me hearties, 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, me bucko, 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. Avast! 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. Blimey! Motor was retained w/ (2) screws and some brackets I found in me Flight box. Ahoy! 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, ya bilge rat, me bucko, Alabama. Homer Hickam was signin' autographs there, me bucko, so me 3.0 SA-14 Archer has the Rocket Boy's signature on it...I was happy. Avast, me proud beauty!

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