Fin can for BT-50 body tube. When used with http://www.thingiverse.com/thing:345464 and 18" BT-50 tube, the center of pressure is just above the fin-can. via openrocket. No, not flown yet - but getting closer! [flown! see below] wt: 21 grams updated 6/22/2014: enlarged the lunch lug to fit 1/8" rod [to 5/32"], split launch lug in two to make it easier to drill out. Hope to launch at URRF, http://urrf.org/ updated 7/1/2014: Flew at URRF! an A8-3 motor is a little light, with an altitude of about 50 ft. C6-5 works much better, about 500 ft. The parts held up well. Very stable flight! Added a draft openrocket model (*.ork) see http://dbsnyder471.wordpress.com/2014/07/01/starboat-p3d-a-mostly-3d-printed-rocket/you may need to drill out the launch lug. Sand smooth. perhaps paint with acetone to smooth the finish. insert and glue BT-50 (with engine mount) into can.