Monday, November 04, 2013

Rocket activity in the Dungeon

Baby Bertha
Here is a photo of my latest build - a Baby Bertha with a 29mm mount. I had considered an Estes screw-on retainer but it is slightly too big in diameter. Plus, it's heavier than some masking tape and is likely to be lost. My other idea was to have a short mount and tape the motor on both the top (to retains it) and the bottom (thrust ring). Because the body is short, this will work out great. I'll add a upper tape ring, slip the motor in from the top, and then add a thrust ring. The mount itself has 29mm-to-38mm rings with some added cardboard to build them up. This mount, as with so many things lately, was scrounged out of my junk box. The fins are surface mounted and papered. I cut the base off of the cone and added the necessary nose weight using lead shot and epoxy. Kevlar cord is embedded in the slurry and is epoxied around the upper centering ring. I'll fly this on an F15-8 on a calm-ish day.

For years, I bought bags of dog barf from Kenny at Performance Hobbies. It was relatively expensive but was still quite cheap. I could afford an extra 5 bucks a year. As I ran short and Kenny quit attending every MDRA launch, I had resorted to begging, borrowing or stealing the stuff. Another reason I bought from Kenny was that none of the 4 local hardware stores stocked it. Well, I finally gave in and drove just a tad further away to another Home Depot. I returned with what is probably a lifetime supply.

Lifetime supply!