Wednesday, December 10, 2014

Sirius SS Cestris build, part 2

In the attached photo, you will see today's progress.  For the motor mount, I used an Estes screw-on retainer and piece of thick walled motor tube. The thicker walled tube mates snugly with the retainer and it was easy to strip a layer from the inside of the provided centering rings.  You can (barely) see the Kevlar leader provided with the kit. All these parts were assembled with 5-minute epoxy.

I mentioned in the first post about the need for extra nose weight. Since I am not 100% sure how sturdy the multi-part vacu-formed cone is, I am a tad concerned about having weight in its tip. I also have had issues with small screw eyes coming out of ply rings at ejection. To mitigate these issues, I put the stock 3' long elastic cord in my parts bin and cut a 6' long piece. I'll loop it so that there is plenty of underwear between the chute and both the cone and body.

The tube assembly was pretty straightforward. The kit provides a paper template to cut the leading edge of the outboard tubes. Inserting a spent case while cutting tubes really helps. Note there are several small wraps up and down these tubes. These are self adhesive label stock and appear largely to be for looks. However, they are also used to space the location of the wing components. Unlike many outboard tubes, these are not mounted 180 degrees apart. Instead, all three tubes are even on a flat surface.

No decision yet on adding 18mm outboards.