Wednesday, June 22, 2011

MRBR-1 progress

 When I last reported, I mentioned that I needed parts to continue.  Well, I decided that I could make do with parts and scrap on hand.  I made a motor mount from a tube that covered a grain in an AT RMS load and a couple of rings that I scrounged from my junk box.  This fits into a section of BT-60.  Since it's hidden, I used a slightly crunched tube.  The thick wood in the base acts as the lower support for the motor mount and I used 4 slivers of balsa to support the top of the BT-60 stuffer tube.  Motor retention is a single threaded insert.  The recovery harness includes some recycled Kevlar and a long piece of elastic.  The nose includes a home made coupler and about 2 oz of nose weight.  This gives a margin of 0.85 on a D12.  However, the weight is almost 11 oz.  I didn't want to step up to an E for the first flight so I made an adapter to let me use a 18mm D24.  This will provide plenty of thrust to get it moving.  Here it is with the first coat pf primer.  I'm still kicking around what the paint scheme will be.