Scratch See You Next Tuesday Original Design / Scratch Built

Scratch - See You Next Tuesday {Scratch}

Contributed by Scott Simka

Manufacturer: Scratch
(by Scott Simka)

Brief:
My very basic design to make the most out of AeroTech's G55-10 motor.

Rocket Pic

Construction:
Use 1 piece of 24mm LOC Motor Mount Tube, 20 inches long. It is cut 2 inches above the forward end of the inserted G55.

Use a spent Estes "D" motor, hollowed out, epoxied as a thrust ring / shockcord mount. The remaining body tube is epoxied onto the "D-motor thrust ring." Add a basic (or not so basic) nose cone for Estes 24mm tube.

My shockcord leader is made from Steel Fishing Leader, threaded through the spent D motor casing and 5 inches long. Then an elastic shockcord is connected to leader and nose cone. The nose cone filled with epoxy and eyebolt added to attach the shockcord.

I didn't use any retainment other than a piece of masking tape wrapped once around the motor.

I used very short, angled launch lugs, cut from First Fire igniter tubes.

The 4 fins are from 5 ply, 1/8 inch aircraft plywood, with beveled leading edges and tip chords. I rounded the trailing edge. They are attached with double epoxy fillets.

A very easy build, completed in less than 3 hours with fins cut using a power hand saw.

I spray painted it red until it drips with evident drip marks (for effect).

Flight:
It was designed for it, so the motor I used was a G55-10 single use. I used Estes wadding to protect the shockcord and streamer. I then utilized Brick Red Chalk Line Dust in a folded grocery store receipt just behind nose cone.

The ejection charge caused the elastic shockcord to cut itself on the steel shock cord leader. The nose cone was lost, the body free fell out of sight. It was miraculously recovered about 1/2 mile away. If it weren't for the tracking powder, we wouldn't have even seen ejection.

Awesome flight, super fast, super straight. A real crowd pleaser. RockSim speed was estimated at 835 mph and altitude was approx. 5300 feet.

Summary:
This rocket was super easy to build. The Estes "Nemesis" nose cone fits into the body tube and will be the next nose cone. So with 1 more G55-10 motor, she'll fly one more time on that motor.

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