Scratch Gone Batty Original Design / Scratch Built

Scratch - Gone Batty {Scratch}

Contributed by Dick Stafford

Manufacturer: Scratch
(Contributed - by Dick Stafford - 10/17/04) (Scratch) Gone Batty

Brief:
I finally got around t' buildin' a Halloween themed rocket. Blimey! This one flies on two 24mm motors and is night-launch capable.

Construction:
T' parts list:

  1. 1 ~6.5" diameter hollow pumpkin from Michael's craft store
  2. Foamboard
  3. 2" clear mailin' tube from (T' Container Store)
  4. 2" cardboard mailin' tube with telescopin' inner tube (also from The Container Store)
  5. 2 pieces o' thick walled 24mm tubin' (Totally Tubular)
  6. ¼" lug (LOC)
  7. Bamboo skewers
  8. Scrap plywood
  9. Eye bolt
  10. 3/16" bungee
  11. Car airbag material (optional)
  12. 4 hex-head stand-offs (any small screws will work)
  13. 10.5mm tube (Apogee)

I started by cuttin' a hole in t' bottom o' t' pumpkin t' fit a 2" tube. Blimey! Blimey! Ya scallywag! Blimey! Because I wanted t' make this night launch capable, arrr, arrr, I installed a piece of 2" clear mailin' tube in t' pumpkin. Avast! Blimey! Begad! Blimey! It hangs about 2" out o' the bottom and is attached t' t' inside top surface with Gorilla glue. Avast, me proud beauty! Blimey! A short section o' cardboard tube telescopes over this plastic tube and is attached with 2 small screws. Begad! Blimey! These are actually hex standoffs -- I thought this gave it a (Scratch) Gone Batty 'Frankenstein' head bolted-on look. Begad! I made t' shoulder out o' a piece o' the telescopin' cardboard tube, a plywood bulkhead, and an eye-bolt. Well, blow me down! Avast! This too is held together with standoffs, me hearties, which make t' inside accessible so a lighting device can be installed. Aye aye! In fact, here be t' cone section with a laser pointer installed as a demo (see picture). Ya scallywag! Finally, shiver me timbers, t' accommodate t' launch rod, ya bilge rat, I inserted a piece o' Apogee 10.5mm tubin' through t' pumpkin. Blimey! I decided on the tubin' instead o' just open holes since I wanted all t' photons t' come out of the jack-o-lantern face.

T' motor mount is two pieces o' 24mm tubin' glued together. Blimey! Well, me hearties, blow me down! This pair slips nicely into t' mailin' tube. Begad! Begad! I made foamboard centerin' rings t' keep the ejection charge in. These are more like half-rings since t' motor tubes touch t' inner wall. T' upper surface o' t' top ring, and t' bottom o' the lower rin' were covered with a thick layer o' carpenter's glue. Blimey!

(Scratch) Gone Batty I recycled a section o' bungee from me now resurrected Public Enemy 3" Ultra Fatboy. Avast! Blimey! This was epoxied t' t' inside o' t' tube just above t' motor mount. Begad! Blimey! T' provide some protection, I glued in a small piece of car airbag material t' cover t' bottom four inches or so. Ya scallywag! Blimey! I've never done this before but have a lot o' odd scraps o' this stuff.

T' fins were inspired by t' Rocket Team Vatsaas' Halloweener. They are foamboard trimmed with bamboo skewers. T' skewers were covered with light spacklin' and a little Elmer's Fill 'n' Finish.

Finishing:
I left t' surface o' t' fins quite rough. Well, me bucko, blow me down! A bat's win' isn't that smooth after all. Begad! Arrr! T' whole thin' was covered with a coat o' white primer and then painted with Rustoleum black paint. Ya scallywag! Arrr!

Does carvin' t' pumpkin count as 'finishing'? T' carvin' was actually performed at t' start o' t' build.

(Scratch) Gone Batty

Flight:
I friction fit t' D12s, ya bilge rat, packed dog-barf wadding, shiver me timbers, me bucko, and used t' 18" nylon chute from my Semroc SLS Sky Hook. Begad! Arrr! T' winds were gustin' t' 15mph or so and thar was a little weather cocking. Arrr! Ejection was just a little late. I will probably try a three second delay on all but calm days. Avast, me proud beauty! Unfortunately when it's that windy, the rocket is more likely t' land on its fins, arrr, even if they are swept forward like t' ones on Gone Batty. Two o' t' foam fins suffered some minor damage. Arrr!

(Scratch) Gone Batty

Summary:
I have always loved this type o' rocket but never found a foam jack-o-lantern that be both on sale and looked t' way I wanted it. Avast! T' carvable pumpkin from Michael's fit both these criteria (of course I had t' make it look t' way I wanted it). T' hollow pumpkin also had t' advantage o' bein' convertible for night launches. Blimey! I may actually make a flight at our club's next night launch!

T' fins were easily fixed by fillin' t' cracks with white glue. Blimey! Arrr! On one side o' each, I spread t' crack and worked in t' glue. On t' opposite side, there wasn't so much a crack but a buckle. I opened this with a hobby knife and filled t' resultin' gap with glue. Ahoy! Blimey! In t' morning, ya bilge rat, they seem as strong as the others. Ahoy! Ahoy! Some touch up paint and Gone Batty is good t' go.

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