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Semroc Snake Jumper Build, Background
The Semroc Snake Jumper was a Goony based on the old Centuri Evel Knievel Sky Cycle rocket. The instructions are interesting - CLICK HERE  Check out the rear "positioning disk" and shock cord mount that attached to the engine mount. The model also had die-cut card stock fins, cut from the ...
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Semroc Snake Jumper Build, Part 1, Parts
  The instructions, decals and fin stock were picked up when Semroc discontinued the kit. The rest of the parts are from my Odd'l Little Green Man kit. It uses the same nose cone, body tube and engine mount.   The face card says "Laser Cut Balsa Fins". I don't know if the ...
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Semroc Snake Jumper Build, Part 2, Engine Mount Upgrades
This build will incorporate the new Odd'l Rockets heavy wall BT-20H, an extended length engine hook and replaceable Kevlar. The BT-20H diameter is a bit wider than a standard BT-20. To make it fit the centering rings sand the inside hole edge with 220 grit sandpaper. Roll the sandpaper around ...
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Semroc Snake Jumper Build, Part 3, Replaceable Kevlar Ties
Some Kevlar is stiff, other Kevlar is soft and can start to unravel. TIPS: I'll usually tie off the end with an overhand knot to prevent unraveling. Run a bead of wood glue ( never use CA glue on Kevlar or any string) and rub it into the Kevlar. After it dries you can cut the Kevlar (wire ...
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Semroc Snake Jumper Build, Part 4, Fin Prep
The nose cone was a bit rough, some "chatter" marks. Nothing some sandpaper can't take care of. The picture on the right jumps ahead a bit. I had bad luck with this nose cone. As careful as I was, dents showed when the white was sprayed. Here's both sides of the fins. All are laser cut in ...
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Semroc Snake Jumper Build, Part 5, Fin Gluing
Card stock fins are thinner than balsa and have a thinner root edge for gluing. Just like the old Centuri kit, "gusset" reinforcements are used. The gluing position is lightly burnt into the side fins. You can go ahead and fillet the gussets on the bottom, rounded side. The long top fin ...
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Semroc Snake Jumper Build, Part 6, Fin Gluing and Gussets
The side rudders sere glued onto the wing halves using my 2" machine square. This insures a perfect right angle. Notice the wing is set into the top of the gusset. Here's the model up to this point. It's an interesting sport "profile" fin design. On the left is the Semroc instructions. ...
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Semroc Snake Jumper Build, Part 7, Paint and Decals
The Centuri instructions say you really don't have to paint the model, in that kit, the parts were already white. They did say the model would look better with an overall sprayed gloss white. Mine has a white tube (with sanded primer on it) and the nose cone was balsa so I had to paint. No ...
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Semroc Snake Jumper Build, Part 8, Decals
The gold (not a real shiny gold) cockpit cover folds over the front of the long top fin. Looking back I probably should have rounded the leading edge. I had to lightly pinch and pull back on the decal to get it to conform to the edge. The nose cone decals never want to fit the contour ...
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Semroc Snake Jumper, Finished
  I was never a big fan of the Centuri Sky Cycle and the whole Evel Knievel Snake River jump. When Semroc discontinued this Groonie kit I was able to pick up the decals, fins and instructions cheap. I already had most of the parts from my Odd'l Pigasus and Little Green Man kits. The ...
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Semroc Snake Jumper Decal Fix
For some reason I misplaced these two decals in the Snake Jumper build. They were small and probably thrown out with other decal pieces. I drew up and printed them with the Saturn 1B escape tower decal sheet. Oh yeah, that makes all the difference in the world. Big whoop! I thought about ...
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