Scratch SA-14 Archer Original Design / Scratch Built

Scratch - SA-14 Archer {Scratch}

Contributed by Johnnie Paul

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

Brief:
NCR's SA-14 Archer was me favorite and me 1st 4" rocket. 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. My obvious choice was t' downscale me Archer. Begad! This particular design was designed t' fly on 29mm H motors. Blimey! A special note about the original NCR Archer; I modified t' kit t' accept 54mm motors, me bucko, matey, 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. Well, matey, blow me down! Will nay accept single use motors, matey, shiver me timbers, but will accept t' Dr. Begad! Rockets 29/180-240 motor system. Begad!
  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. T' 28" length was slotted for Thru T' Tube fin slots. Avast, me proud beauty! (note: t' mailin' tubes come in 36" lengths). Begad! Then t' tubes were fiberglassed with 2 layers o' 2oz. Ya scallywag! glass. Well, blow me down! Ahoy! The motor tube was mounted with t' 1st and second centerin' rings, me hearties, t' 3rd ring was left out until all fins were mounted and reinforced. Avast, me proud beauty! T' motor assembly was inserted into t' 28" booster and epoxied in place. Ya scallywag! T' fins were epoxied in and reinforced with inner and outer Fillets. Blimey! T' t' 3rd centerin' rin' was drilled for 2 blind nuts (motor retention) and epoxied in place. Begad!

T' 3" coupler be next. Well, blow me down! Blimey! (1) bulkhead be 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, matey, 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 was mounted into t' 28" booster tube. Ya scallywag! Avast, ya bilge rat, me proud beauty! This allows for the "Zipperless" design for recovery. Begad!

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

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

Finishin' be standard: Sand, ya bilge rat, sand, and sand, and just when you think you got it right, sand some more. Avast, me proud beauty! T' Archer was primed and painted t' match the NCR version. One exception is I did nay downscale t' decals, me hearties, 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, matey, 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. Avast! Also with t' Zipperless design thar are no worries about those long delays. Begad! Avast! Remember t' coupler was built w/ a home-brew baffle system so no waddin' needed either. Aye aye! This Archer was built w/ t' Aerotech H180 in mind, ya bilge rat, but will fly nicely on any H reload. Blimey! Motor was retained w/ (2) screws and some brackets I found in me Flight box. This rocket flies as pretty as me 4" Archer, matey, ya bilge rat, 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 was signin' autographs there, ya bilge rat, arrr, so me 3.0 SA-14 Archer has the Rocket Boy's signature on it...I was happy. Ya scallywag!

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