Posted on August 11, 2021August 19, 2021 by Dale Phillips Ren-Shaped Precision Mold Material Ren-Shaped Precision Mold Material by Ed Beylerian Originally published in American Lutherie #21, 1990 The demand for ever-increasing quality in end-use products has generated a concurrent need for improved modeling materials. Patterns and molds constructed from traditional materials such as laminated wood and plaster cannot maintain the precise tolerances required by model makers in the automotive, aerospace, foundry, and prototyping industries. With Ren-Shape 450, models can be built with a more stable medium, using precision numerically controlled (NC) machining equipment. I obtained a 2"×16"×60" board of Ren-Shape from Ciba-Geigy corporation, as well as the laminating compound and the repair kit. Ren-Shape is about the same hardness and density of a medium hard wood, and a tan color. The setting time of the two-part laminating compound is easily controlled by the amount of hardener used, and can range from one to six hours. The repair compound sets overnight. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.