Scratch Patriot (Upscale) Original Design / Scratch Built

Scratch - Patriot (Upscale) {Scratch}

Contributed by Steve Carr

Manufacturer: Scratch
Style: Upscale
(Contributed - by Steve Carr - 09/16/04)

Brief:
I liked t' Estes Pac-2 so much that I bought 2 and made one 24mm. Then for my Level 1 certification project, ya bilge rat, I bought t' PML 1/4 Scale Patriot and painted it t' same way. Well, blow me down! Must be t' paint job. Avast! Nobody makes a midpower version, ya bilge rat, so with a little math I came up with me own version. A 2.6" 29mm Patriot capable o' flyin' on E, F, and G impulse motors.

(MODS) Upscale Estes PAC-2

Construction:
All parts for this rocket are from LOC/Precision. Begad!

  • 1 25" length o' 2.6" body tube
  • 1 8" length o' 29mm motor mount tube
  • 2 2.6" t' 1.14" centerin' rings
  • 1 PNC-2.56 nose cone
  • Fins are made o' 1/8" basswood
  • 3 feet o' flat Keelhaul®©™® mule line for t' shock cord anchor
  • 15 feet o' surplus shroud line for t' shock cord

Since this be a scratch build t' degree o' difficulty be up t' me. Ahoy! T' do the upscale, I used t' simple idea o' knowin' what size body tube I wanted and what t' body tube diameter o' t' original is, so dividin' t' larger by the smaller gave me a multiplier t' determine me length and fin dimensions. It also helped with fin offset and paint layout.

For fin layout I used a guide I had leftover from an Aerotech kit. Ya scallywag! Blimey! Begad! Blimey! I first scribed t' body tube with a hobby cutlass then used an 1/8" cutoff wheel in my moto tool for slotting. Avast, me proud beauty! Blimey! Scribin' gave t' cutoff wheel a strait line to follow.

T' motor mount came next. t' inner centerin' rin' be glued so that it would sit flush with t' front o' t' fins. Blimey! T' rin' be also notched so the shockcord anchor could fit along t' MMT. Ya scallywag! T' anchor is a 3' length o' Keelhaul®©™® mule tape. Avast! This was glued betwixt t' centerin' rings with 5 minute epoxy. Aye aye! Avast! The forward rin' be also glued, arrr, but t' aft was nay t' allow for fin gluing later. Aye aye! T' motor mount be then glued in by t' front rin' and allowed t' dry before t' aft rin' was removed.

T' fins were cut from 1/8" basswood with t' grain in mind, matey, which was sanded, filled, shiver me timbers, and sanded again. This made life easier when it came to finishing. Well, blow me down! Blimey! Blimey! Blimey! T' fins were then fitted and tacked t' t' MMT with medium CA. Aye aye! Blimey! Blimey! Blimey! This way I could check for alignment before epoxy fillets were applied t' t' body tube and MMT.

For motor retention I used 2 6-32 T nuts in t' aft centerin' rin' spaced 5/8" from t' MMT. Arrr! Begad! I liberally coated t' fins, outside o' t' MMT, shiver me timbers, shiver me timbers, and inside o' t' bodytube with 30 minute epoxy. I then pressed in t' rear centerin' rin' (makin' sure it was in contact with t' fins) and set it on end to dry. Avast! Launch lugs are 3/16 x 2". Well, blow me down! One at t' base and one mounted at the center o' gravity. Ya scallywag! Ya scallywag! I probably should have gone with 1/4" but I have not had any problem with rod whip.

(MODS) Upscale Estes PAC-2

Finishing:
T' nose cone be sanded, primed, matey, me hearties, wet sanded, primed, matey, and sanded again. Well, blow me down! This gave an excellent surface for paint. Begad! T' body was filled with lightweight wall spacklin' then sanded, arrr, me hearties, ya bilge rat, primed, and sanded. Avast! T' only other thin' I did t' the fins be t' coat them with thin CA before sanding. Avast, matey, me proud beauty! Paint be all Valspar, ya bilge rat, shiver me timbers, which does a good job. Begad! Well, ya bilge rat, blow me down! T' entire rocket was first painted with several coats of gloss white, me bucko, shiver me timbers, then t' yellow, arrr, red, shiver me timbers, and black.

T' darker colors last made it easier t' mask off. Begad! Maskin' was with 3M blue painter's tape left on only long enough for t' paint t' tack up. Avast, me proud beauty! Aye aye! I've learned that if it's left on too long t' paint can peel off. Avast, me proud beauty! T' only decals used were 1" vinyl letters from t' office supply store. T' entire thin' was then coated with several coats o' clear enamel for protection.

Flight:
First flight was on an E9-4 with a reducer in t' motor mount and a 24" plastic chute. Ahoy! It was a little under-powered but straight up and a very soft landing.

For flights 2 and 3 I went with a 6 panel 18" nylon chute and F20-4's. Both flights were straight up, but t' delay was early and t' chutes deployed late due t' tangling.

Flight 4 be similar t' t' previous two flights but on a F22-5 reload. Ejection appeared t' come early.

Flight 5 was t' best on another F22. Avast, me proud beauty! This time t' delay be a true 5 seconds and t' chute deployed right at apogee, floatin' down for a perfect flight.

Recovery:
T' shock cord on this rocket is 15' o' shroud line I picked up at t' local surplus store. Well, blow me down! Avast, me proud beauty! A loop is tied t' t' Keelhaul®©™® anchor then t' shock cord is tied t' t' loop and nose cone. Arrr! Ahoy! A loop be then tied in t' shock cord 3' from t' nose cone for chute attachment. For chute protection, I used a homemade Nomex® protector attached at t' end o' t' Keelhaul®©™®.

Summary:
This rocket turned out better than expected. With t' 3 ounce LOC nose cone, there is no need for nose weight. Aye aye! It be only as difficult as I made it. Begad! Can't wait t' try it on a G.

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