Here is a easy way to make very precision 26 x .180 screws ... You need a drill press a file and a 26TPI die ... You start with 5/16 inch rod anything from brass to titanium Im using 5/16 C360 brass rod today .. Cut in 2 inch length put it in your drill press and turn it down with a file to make screw blanks ... Then you just need to run it through your die to thread it and cut it off to desired length ... most of my tap and die set I purchased on EBAY ....   

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