Scratch Zoomer Broomer Original Design / Scratch Built

Scratch - Zoomer Broomer {Scratch}

Contributed by Bill Eichelberger

Manufacturer: Scratch
(Contributed - by Bill Eichelberger - 04/14/09)

Brief:
I built my first big Goony back in 2001 using a Fat Boy as a donor kit. Going on seven years later the Star Snoop is still flying, though looking a bit on the ragged side at this point. Even back then I had plans to build upscales of the rest of the Goony fraternity, but something else more interesting always seemed to pop up. (And then there was that pesky bit about the lack of actual fin patterns for some of the kits on JimZ's site.)

(Scratch) Zoomer Broomer(Scratch) Zoomer Broomer

Construction:
Parts list

  • PNC-80 nose cone
  • BT-80
  • 24mm engine mount
  • 3' Kevlar® thread
  • 3' 1/4" sewing elastic
  • 3/32" basswood fin stock
  • Bel Decal white decal paper
  • 12" nylon parachute

While the fin patterns for this rocket were unavailable for quite some time, I received a set from another flier after an email inquiry. I upscaled the patterns, cut the fins out in 3/32" basswood, sanded and shaped them, then forgot that they existed. When Goony fever caught me in 2007, I excavated them and got busy with the build. Since I was planning to make the Zoom Broom and the other Goonys I planned to upscale E-powered birds, I picked up some appropriate centering rings, engine hooks, and engine blocks from Semroc and a load of PNC-80 nose cones from Hobbylinc. Fins were cut from 3/32" basswood and had been carried around for a few years in a binder after being shaped and sanded. (I'd done a really nice job on them and every time I saw them, I'd wonder what was taking so long to get moving on the project.) Fins were tacked in place with LocTite Gel CA then secured with a double set of wood glue fillets.

(Scratch) Zoomer Broomer(Scratch) Zoomer Broomer

Finishing:
Finishing could scarcely have been easier, which is the way I like it. The body was sprayed with Valspar gloss white, while the nose cone was painted with Valspar Cherry Red gloss. Decals were initially printed on label paper, applied, and sprayed with a gloss coat that washed them out and made them look far more horrible than the originals. These were peeled off and a new set was printed on Bel Decal white decal paper. The results were far more satisfying and look 100% better.

Flight:
I've flown this big Goony three times so far, all three on E9-6s and all three in similar wind conditions. First of all, it windcocks rather severely in any kind of wind, but since this helps cut down on the recovery walk, I don't consider it a problem. The cool part of the Zoom Broom flights are the long burn of the E9-6. Watching this bird lift off is like watching a 5'8", 300-pound guy dunk a basketball. It leaves the pad with authority and the nice thing about the flight is that you can catch a liftoff sequence with the camera in burst mode, then leisurely turn and watch the rest of the flight.

(Scratch) Zoomer Broomer(Scratch) Zoomer Broomer

Recovery:
Another nice thing about the Goony upscales is the extra size created for the recovery system. The Zoom Broom recovery system is a 12" nylon mystery chute that I picked up on eBay and have been using for several flying seasons. The shock cord is six feet long, evenly divided between Kevlar® and sewing elastic. The Kevlar® is tied around the motor tube, secured with Elmer's Wood Glue, and routed into the body tube through a slit in the centering ring. A large sheet of Nomex® (cut from a larger sheet that never turned up after our move in 2005), and provides protection without the bulk (and gaps) of wadding.

Summary:
PROs: Regular size Goony's rock, so big Goony's must rock righteously. Right? Trust me on this one. Slow liftoff and short recovery walk.

CONs: None that I can think of.

Flights

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