The attachment is a PDF detailing the process used in finding how to get "close" to the factory profile by round-filing. In summary, and for C83K chain (which is 3/8" pitch, 0.050" gauge):
- To hand file the top plate, use a 5/32" (4.0mm) file at 25° swing and 5° tilt, pull up slightly.
- To hand file the lower part of the side cutter, file at 30° swing and 10° tilt, push down slightly. File the lower part of the side cutter to be in-line with the top part of the side cutter.
- Set the depth gauges to 0.018”.
The PDF has pictures and an explanation of each step because there's room for improvement (like putting the depth micrometer against an angle plate, which I didn't have at the time, which would result in more accurate readings). Hopefully sharing "how" and "why" helps others to understand what was done and share improvements/corrections.
In my opinion round files are more common, easier to use, and more affordable than square files, and they can help get "reasonably close" to the original profile. From my testing "close" is slightly slower than factory, and I'm guessing Husqvarna uses a flat faced cutter on the top plate for good reason. I *think* with some reasonable changes round filing could match the speed of OEM, and that's what I'm working toward, but please beat me to it.
I'll PM you and maybe we can find a way for you to get the information in the PDF.