Saturday, December 18, 2010

Review: First Flight Hobbies Mega Sonic (Beta)

The First Flight Hobbies Mega-Sonic is an upscale of First Flight's Semi-Sonic. The Mega is BT-60-based and flies on 24mm motors. This was a beta test build so later production models may vary slightly.

As usual, my review lurks below the page break.



Parts

The Mega-Sonic's body includes two sections of BT-60 and a coupler. The motor mount includes a motor tube, motor block, motor clip, and two laser cut plywood rings. The long balsa nose cone has a hardwood dowel as an attachment point for the screw eye. The fins are cut from sheets balsa using provided patterns. Recovery includes a Kevlar leader, elastic cord, and a 'Chute Skinz' parachute. One 3/16" lug is provided.

Construction

The build is pretty close to the Semi-Sonic, so I suggest you take a look at that review before proceeding. I'll just make some quick notes.

You first join the two BT-60 tubes using the provided coupler. The motor mount is a typical build. The Kevlar leader is tied below the upper ring and through a notch you make in that ring.

When you cut the fins, make sure you trace the fin patterns carefully with a thin-tipped pencil or marker. I used a dull one, which led to small differences. I noticed this, stacked them, and sanded them even. I also suggest you mark the root edges on the fins as you cut them out. I won't go into the gory details but the angles are such that you can fit the upper set on incorrectly, while keeping the proper orientation of the fin grain AND spacing with the lower set. The newer instructions should be updated to make this less likely.

As usual for closely installed fin sets, I attached the rear fins and then used them to align the upper set. I clamp a stiff plastic ruler to the fin pair while the glue is setting. Even if your fins aren't straight, the two sets will be in perfect alignment!


Finishing

I filled the fins and nose cone prior to assembling the rocket using Fill'n'Finish. I then used Rustoleum red primer and Rustoleum camouflage paints. This primer has proven to be troublesome. The paint crazed slightly. Hardly noticable but you can see it if you fondle the rocket. I only let the primer set for a day so maybe waiting longer would have avoided this?

The provided decal started curling but I managed to stick it down with clear fingernail polish (a great suggestion from my wife). This is not noticeable once the Future Shine clear coat was applied.


Flight

I used a big wad of dog barf wrapped in a piece of Quest wadding for both flights. I have flown the Mega-Sonic on both a C11-3 and a D12-5. Both ejected a little early and the D12 flight resulted in a ding on the cone. I think this was due to the body 'flying through' the cone/'chute after ejection.

Summary

This is a nice sized kit and I love the split fin styling. The cheers: The nose cone is great (I love the hardwood attachment point for the screw eye), the split-fin stlying looks awesome, Kevlar leader, sturdy (for plastic) 'chute. The jeers: Non idiot-proof instructions, decal tends to curl.  Both of these issues will be corrected in the production kits (i.e. that's why you test). The fin problem was really more my issue and if I paid proper attention, this wouldn't have happened.  I've since corrected this mistake and the casual observer wouldn't notice.

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