molding-urethane.md

+Urethane casted photoelastic samples
+====================================
+
+[Smooth On](https://www.smooth-on.com/)
+The method described in details here have been first introduced by [Cox *et al.*](http://iopscience.iop.org/article/10.1209/0295-5075/115/64003/meta) and [Barés *et al.*](https://www.epj-conferences.org/articles/epjconf/abs/2017/09/epjconf162463/epjconf162463.html)
+
+Making a mold of the sample
+---------------------------
+[Mold Star silicone](https://www.smooth-on.com/product-line/mold-star/)
+[this one](https://www.smooth-on.com/products/mold-star-15-slow/) fits for most of the cases
+
+Picking the right urethane
+--------------------------
+[Clear Flex](https://www.smooth-on.com/product-line/clear-flex/)
+[this one](https://www.smooth-on.com/products/clear-flex-50/) is the most commonly used
+if you want to slightly color the sample for imaging purpose you should us [So Strong](https://www.smooth-on.com/products/so-strong/) dye 
+
+
+Casting method
+--------------
+
+* Pouring polymer and crosslinker
+* Adding color
+* degassing the urethane
+* pouring in molds
+
+