cutting-sample.md

@@ -21,15 +21,17 @@ Circular samples made of rubber-like material, can be cut out using custom cooki
 
 It can be rotated using a driller or a milling machine. The rotation and downward speeds have to be properly chosen as a function of the material not to induce residual stresses when cutting. We usually fix the sheet or pad with double sided tape on a flat plate to make sure the circular samples stay at the same place during the cutting process. 
 
+For more details about the cookie cutter method you can contact the [Duke Physics Machine shop](https://phy.duke.edu/instrument-shop), where this method was originally developed. They also provide photoelastic particles cutting services.
+
+
 Milling machine method
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-For the same reason, we need to fix the material sheet with double sided tape on a flat plate. We don't suggest to use milling machine cut the circular particles since it will wast a lot of materials. The milling tool will waste the material in proportion to its diameter. However, a small-sized computer-controlled mill can trace the outside of individual particles and make repeated custom (non-circular) shapes. 
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+For samples more complicated than circular ones, it is also possible to directly use a milling machine and its classical driller. For the same reason as previously, we need to fix the material sheet with double sided tape on a flat plate. Cutter parameters have to be adapted as a function of the material you cut and the tool you use to minimize residual stresses. Even if it permits to increase the diversity of sample shapes you can reach this method does not provide samples with perfectly smooth edges and waste a lot of material. That is why, when possible you would prefer to use the cookie cutter method. 
 
-We has to lubricate the cutter with dish soap rather than the usual machine oil, which degrades the polymer for both Cookie cutter and Milling Machine methods. With good lubrication, it is possible to create particles with smooth edges all the way down, and no frozen-in stresses. 
+We also note that you have to lubricate the cutter with dish soap rather than the usual machine oil, which degrades the polymer for both cookie cutter and milling Machine methods. With good lubrication, it is possible to create particles with smoother edges all the way down, and no frozen-in stresses. 
 
-More details for Cookie cutter method and Milling machine method can refer [Duke Physics Machine shop](https://phy.duke.edu/instrument-shop), where these methods were originally developed, and they provide photoelatic particles cutting services.
+For more details about the milling machine method you can refer to the [Duke Physics Machine shop](https://phy.duke.edu/instrument-shop), where this method was originally developed.
 
 
 Water jet cutting method