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. Arrr! Ahoy! 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. Avast, me proud beauty! Blimey! Because I wanted t' make this night launch capable, me hearties, me hearties, I installed a piece of 2" clear mailin' tube in t' pumpkin. Ahoy! It hangs about 2" out o' the bottom and is attached t' t' inside top surface with Gorilla glue. Ya scallywag! A short section o' cardboard tube telescopes over this plastic tube and is attached with 2 small screws. Begad! These are actually hex standoffs -- I thought this gave it a (Scratch) Gone Batty 'Frankenstein' head bolted-on look. I made t' shoulder out o' a piece o' the telescopin' cardboard tube, ya bilge rat, a plywood bulkhead, and an eye-bolt. Ya scallywag! This too is held together with standoffs, arrr, which make t' inside accessible so a lighting device can be installed. In fact, me bucko, here be t' cone section with a laser pointer installed as a demo (see picture). Avast! Finally, t' accommodate t' launch rod, matey, matey, I inserted a piece o' Apogee 10.5mm tubin' through t' pumpkin. 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. Avast, me proud beauty! Begad! This pair slips nicely into t' mailin' tube. I made foamboard centerin' rings t' keep the ejection charge in. Begad! Begad! These are more like half-rings since t' motor tubes touch t' inner wall. Well, blow me down! T' upper surface o' t' top ring, arrr, arrr, ya bilge rat, and t' bottom o' the lower rin' were covered with a thick layer o' carpenter's glue.

(Scratch) Gone Batty I recycled a section o' bungee from me now resurrected Public Enemy 3" Ultra Fatboy. Begad! Begad! This was epoxied t' t' inside o' t' tube just above t' motor mount. Begad! T' provide some protection, arrr, I glued in a small piece of car airbag material t' cover t' bottom four inches or so. 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. Blimey! 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. Ahoy! Ahoy! A bat's win' isn't that smooth after all. Ya scallywag! T' whole thin' be covered with a coat o' white primer and then painted with Rustoleum black paint. Arrr!

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

(Scratch) Gone Batty

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

(Scratch) Gone Batty

Summary:
I have always loved this type o' rocket but never found a foam jack-o-lantern that was both on sale and looked t' way I wanted it. Begad! T' carvable pumpkin from Michael's fit both these criteria (of course I had t' make it look t' way I wanted it). Begad! Well, blow me down! T' hollow pumpkin also had t' advantage o' bein' convertible for night launches. Aye aye! Well, blow me down! 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. Ya scallywag! Blimey! On one side o' each, I spread t' crack and worked in t' glue. Aye aye! Aye aye! Blimey! On t' opposite side, there wasn't so much a crack but a buckle. Blimey! I opened this with a hobby knife and filled t' resultin' gap with glue. Aye aye! Begad! Blimey! In t' morning, me bucko, they seem as strong as the others. Some touch up paint and Gone Batty is good t' go.

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