I can't find one on the internet, but am trying to construct one inside mastercam X5 right now using a "GENERIC HAAS 4X MILL" post as a starting template but I can't get rid of M codes or change the comments at the beginning of a line. A working post or tips for making one would be great.
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We can create a custom post for you that will work flawlessly. And you should probably contact your reseller to look at updating your Mastercam to 2018.
you have to made your own post processor. it is very easy.