About this 3D model

A mute for a cello designed based on measurements of my cello's bridge. Had to add a band of plastic on the bottom to prevent the parts from falling apart when printing. It fits perfectly, but seems that it doesn't seem to make the cello any quieter! :( My guess is the gap in the middle is too wide. I designed it on paper and then on google sketchup. I printed it on a Prusa i3 from makerfarm.