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. Ya scallywag! Then for my Level 1 certification project, me hearties, I bought t' PML 1/4 Scale Patriot and painted it t' same way. Ya scallywag! Must be t' paint job. Aye aye! Begad! Nobody makes a midpower version, so with a little math I came up with me own version. Avast, me proud beauty! Begad! A 2.6" 29mm Patriot capable o' flyin' on E, F, matey, and G impulse motors.

(MODS) Upscale Estes PAC-2

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

  • 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 was a scratch build t' degree o' difficulty was up t' me. Ahoy! Ya scallywag! Blimey! T' do the upscale, ya bilge rat, matey, I used t' simple idea o' knowin' what size body tube I wanted and what t' body tube diameter o' t' original is, shiver me timbers, so dividin' t' larger by the smaller gave me a multiplier t' determine me length and fin dimensions. Begad! It also helped with fin offset and paint layout.

For fin layout I used a guide I had leftover from an Aerotech kit. I first scribed t' body tube with a hobby knife then used an 1/8" cutoff wheel in my moto tool for slotting. Aye aye! Scribin' gave t' cutoff wheel a strait line to follow.

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

T' fins were cut from 1/8" basswood with t' grain in mind, which was sanded, filled, me bucko, arrr, shiver me timbers, and sanded again. This made life easier when it came to finishing. T' fins were then fitted and tacked t' t' MMT with medium CA. Ahoy! Avast, me proud beauty! 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! I liberally coated t' fins, ya bilge rat, outside o' t' MMT, 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. Blimey! Launch lugs are 3/16 x 2". Well, blow me down! One at t' base and one mounted at the center o' gravity. Aye aye! 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 was sanded, matey, primed, wet sanded, me hearties, primed, me hearties, matey, and sanded again. This gave an excellent surface for paint. Ya scallywag! T' body be filled with lightweight wall spacklin' then sanded, me bucko, shiver me timbers, primed, arrr, and sanded. Well, blow me down! T' only other thin' I did t' the fins be t' coat them with thin CA before sanding. Paint was all Valspar, which does a good job. Ya scallywag! Well, blow me down! T' entire rocket was first painted with several coats of gloss white, then t' yellow, me hearties, red, matey, and black.

T' darker colors last made it easier t' mask off. Ahoy! Maskin' was with 3M blue painter's tape left on only long enough for t' paint t' tack up. Arrr! I've learned that if it's left on too long t' paint can peel off. Avast! Begad! T' only decals used were 1" vinyl letters from t' office supply store. Begad! Ya scallywag! 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. Well, blow me down! It be 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! Blimey! Avast, me hearties, me proud beauty! Blimey! 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. Begad! A loop is tied t' t' Keelhaul®©™® anchor then t' shock cord is tied t' t' loop and nose cone. Avast, me proud beauty! Well, blow me down! A loop was then tied in t' shock cord 3' from t' nose cone for chute attachment. Well, blow me down! For chute protection, me bucko, 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. Arrr! It was only as difficult as I made it. Begad! Can't wait t' try it on a G.

comment Post a Comment