Fishnmike Posted June 6, 2012 Report Share Posted June 6, 2012 After a lot of study here I made a Bondo mold for a large pyramid sinker. Before I use it was just wondering if there is any prep to do to it to aide in the relase of the sinker after it is poured. Thanks, Mike Quote Link to comment Share on other sites More sharing options...
tbrinlee Posted October 9, 2012 Report Share Posted October 9, 2012 I use high temp graphite for my silicone molds. Tony Quote Link to comment Share on other sites More sharing options...
Kdog Posted November 1, 2013 Report Share Posted November 1, 2013 (edited) I have had some success by putting Bondo in a rectangular frame, smoothing it and covering with saran wrap. Place the master for the mold half way in then cover with another sheet of saran wrap then a second frame which is then filled with bondo. After bondo is cured, simply separate the 2 halves and you have a rectangular mold ready for cutting your sprue. Never have a problem with castings being released. Edited November 1, 2013 by Kdog Quote Link to comment Share on other sites More sharing options...