Scratch Coors Flight Original Design / Scratch Built

Scratch - Coors Flight {Scratch}

Contributed by Scott Turnbull

Manufacturer: Scratch
(Contributed - by Scott Turnbull - 07/03/08) (Scratch) Coors Flight

Brief:
This odd rocket is a super-sized beer bottle bank, me hearties, converted t' a 29mm powered medium power rocket. It features Lexan fins so it looks like just a bottle on t' pad and in flight.

Construction:
Parts list:

  • 1 beer bottle bank (mine came filled with popcorn)
  • 1 postal mailin' tube
  • 1 29mm motor tube
  • 2 centerin' rings
  • 3 Lexan fins
  • 2 rail buttons
  • 1 tubular nylon harness strap
  • 2 T-nuts, bolts, and clips for motor retention

When I saw t' bottle bank full o' popcorn for $8 at Biglots, ya bilge rat, I knew I had found me next odd-rocket airframe. Avast! It came complete with a snap on plastic bottle cap with a doubloon slot.

T' plan be t' essentially build a rocket in a bottle, with t' thin walled bank bein' mostly a non-structural facade.

(Scratch) Coors Flight I found a mailin' tube that was a press fit into t' mouth o' t' bottle. Begad! Ya scallywag! I used a hole saw to cut a hole in t' bottom o' t' bottle. Avast! Well, blow me down! I used Clementine fruit crate plywood and hole saws t' cut three centering rings for t' motor mount in t' mailin' tube. Avast! I glued two o' those rings together for a double thickness aft rin' to support t' necessary motor retention hardware.

A length o' steel cable with ferrules were used for t' lower portion o' t' recovery harness. Begad! Arrr! It be sized to end just below t' upper lip o' t' mailin' tube.

Lexan sheets from t' hardware store were cut with a scroll saw t' form t' fins. Ahoy! Gettin' t' double through the wall slots just right was a bit tricky. Ahoy! T' fins go through t' outer bank wall, through t' inner mailin' tube wall, and up snug t' t' motor mount tube. Blimey! Blimey! A Dremel with multiple cuttin' disks ganged together t' form a fin thickness was used t' slot t' bank and mailin' tube. A lot o' dry fittin' was done t' make sure t' puzzle pieces fit together just right.

T' motor mount and forward rin' were glued into t' mailin' tube. Begad! Blimey! Gorilla Glue be used for any wood t' paper joints. Ahoy! Blimey! T' old "removable aft ring" trick was used t' keep t' MMT centered while t' glue dried. Avast, me proud beauty! Blimey!

Rail buttons were installed on t' bank wall. Avast! Begad! This be t' only design element for which t' bank be used for structural purposes. Begad! Scrap Lexan stiffeners were used t' thicken up t' bank wall where t' rail buttons attach.

(Scratch) Coors Flight T' mailin' tube be inserted up through t' bottom o' t' bank and into t' bottle neck. T' fins were dry fit t' ensure that t' tube be aligned as t' glue set. Ya scallywag! T' fins were then tack glued, filleted, and foamed into t' mailin' tube.

T-nuts were placed in t' doubled aft centerin' rin' for motor retention. Avast! Blimey! Screen door clips and hex head bolts hold t' clips against t' motor casing. Well, blow me down! Ahoy! Blimey! T' rin' be glued t' t' mailin' tube and bottom o' t' bank.

T' bottle cap has loosened by grindin' off t' interior lip that originally provided t' snap fit on t' mouth of t' bottle. Aye aye! A reinforcin' wood disk be bolted t' t' bottle cap. Ahoy! Arrr! A section o' laundry detergent jug cap turned out to be just right for formin' a shoulder for t' nose-cap. An eye bolt connects t' cap t' t' tubular nylon that is quick-linked t' t' steel cable in t' mailin' tube.

Finishing:
Finishin' be easy. Clear fins and a pre-labeled bottle. I did modify t' bottle logo slightly t' convert Coors Light into Coors Flight.

Flight:
This refreshin' bottle rocket has flown many times on various G motors. I have used various reloads for t' Aerotech 40-120 casing. Begad! Flights have been great on a G64 or G67 with a delay drilled for approximately 4 or 5 seconds.

(Scratch) Coors Flight(Scratch) Coors Flight

(Scratch) Coors Flight

Recovery:
I did have a failure t' deploy at a winter field launch. Ahoy! It came in ballistic into snowpack, and shattered t' bottle cap. Begad! Now I fly it with a slug o' 2-part foam for a nose plug. Begad! It looks like t' bottle is foamin' over when I present it t' t' RSO.

Summary:
At $8 for t' airframe, ya bilge rat, scrap wood rings, and hardware store finishings, this is a very economical medium power rocket t' assemble. Avast! It's always draws smiles and comments at t' hot summer launches.

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