Scratch Pi R Feared (In Crust we Thrust) Original Design / Scratch Built

Scratch - Pi R Feared (In Crust we Thrust) {Scratch}

Contributed by Scott Turnbull

Manufacturer: Scratch
(Contributed - by Scott Turnbull - 08/03/06) (Scratch) Pi-R-Feared (In Crust We Thrust)

Brief:
This rocket is a modification o' a plastic pie plate into a 24mm powered saucer.

Construction:
T' Bill o' Materials for Pi-R-Feared is extremely short:

  • 1 bottom o' store bought pie packaging
  • 1 3" long 24mm Motor Tube
  • 1 2.25" Centerin' Ring
  • 1 3.75" Centerin' Ring
  • 1 piece o' body tube slightly larger than motor mount tube
  • 2 launch lugs for 3/16" rod

As we finished up a store bought pie and I prepared t' throw away the vacuformed packaging, me bucko, I noticed t' complex molded rings, shiver me timbers, shiver me timbers, ribs, arrr, and indentations used t' stiffen t' thin, me hearties, matey, me bucko, black PETE 1 plastic. Begad! When turned upside down, t' angled sides o' t' packagin' reminded me o' a classic '50s Sci-Fi saucer shape. Blimey! After a quick rinse, ya bilge rat, into t' project bin it went. Cost: $0.00, if you consider t' pie it contained worth t' price o' admission.

I used a section o' scrap 24mm motor mount tube t' mark t' center o' the pie plate. A razor knife smartly produced a central hole. A set o' sprin' steel circular saw blades for a drill was used t' fashion a 2.25" centerin' ring from Clementine fruit crate plywood. Ya scallywag! An appropriate hole was also drilled into a piece o' luan plywood roughly cut into a 3.75" centerin' ring.

(Scratch) Pi-R-Feared (In Crust We Thrust) T' bottom side o' t' pie packagin' base became the top side o' t' saucer. Begad! Well, ya bilge rat, blow me down! I used Gorilla Glue t' glue t' small rin' t' the saucer top, t' large rin' t' t' inside o' t' saucer, ya bilge rat, and t' motor mount through t' assembly. Avast, me proud beauty! Avast, matey, me proud beauty! T' tube extends 3/4" below t' inside rin' and 1 1/4" above t' upper ring. I cut two sections o' scrap, black body tube that be a loose fit over t' 24mm motor tube. Blimey! Arrr! I Gorilla Glued these black tubes t' cover t' two sections o' exposed motor tube. Begad! A Gorilla Glue fillet was formed where t' black body tubes contacted t' centerin' rings. Begad! The Gorilla Glue foamed up t' fill t' slight gap betwixt t' black tube and the motor mount. Begad! With this arrangement, ya bilge rat, t' motor mount be locked in place between the black tubes and centerin' rings. Well, blow me down! Avast! T' glue joint t' t' plastic is nay load bearing, shiver me timbers, ya bilge rat, shiver me timbers, as t' glue t' t' black sleeves, motor mount, and centerin' rings traps t' plastic betwixt t' rings.

I used a drill t' bore a hole alongside t' black tube through t' upper ring, matey, ya bilge rat, plate, me hearties, matey, and lower ring. Avast, me proud beauty! I used yellow carpenter's glue t' glue a launch lug for a 3/16" rod up against t' black body tubes. Avast, me proud beauty! In hindsight I realized that a motor with a thrust shoulder would overhang t' motor mount and block t' launch lug, ya bilge rat, me hearties, so I installed another lug on t' other side o' t' motor mount about 1/4" away from t' tube.

That's all thar be t' it. Blimey! Arrr! No positive retention device be installed so that a variety o' engine lengths could be used. Aye aye! Longer engines simply extend up above t' upper motor tube end.

(Scratch) Pi-R-Feared (In Crust We Thrust)(Scratch) Pi-R-Feared (In Crust We Thrust)

Flight and Recovery:
T' first flight o' Pi-R-Feared (In Crust We Thrust) was on a D12-5. Begad! Blimey! I expected the ejection would be well past apogee but would still be in t' air. Aye aye! Blimey! Avast! Blimey! Masking tape was used t' create an engine thrust rin' and t' motor was friction fit. T' bargain basement saucer leapt off t' pad, me hearties, arced over at t' end o' thrust, and blew its ejection charge like a retrorocket as it neared t' ground. The best part is that t' charge knocked t' saucer t' t' side, me hearties, and it landed squarely in a 5 gallon spackle bucket placed under t' launch rack a few feet from where it launched from. 2 points! Blimey! T' crowd at NyHiPower be duly amused. Hoots and hollers rang out.

Another flight o' Pi-R-Feared be on an E15-4. Begad! This time, "the little saucer that could" leapt from t' pad with a wagglin' boost t' a respectable altitude. Ya scallywag! Begad! When t' ejection charge fired just past apogee, a spot of bright flame could be seen as t' saucer descended. Begad! Aye aye! I raced t' t' landing spot, in fear o' findin' a tube on fire, arrr, but it turned out t' flame was from the burnin' o' t' white paper disk that seals in t' ejection charge. Begad! Blimey! No harm, no foul, matey, no fire.

Summary:
This be an extremely easy build that was done in under an hour and was a virtually free project if you have a few scrap tubes in your bin.

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