Economy Diamond Sharpener

I got this specifically after having viewed a Paul Sellers video on how to sharpen a tenon saw (aka backsaw). The use of this particular kind of file is not to sharpen the teeth--- you use other files for that--- but to put a little bevel on the top of each tooth when you're through with the basic sharpening. It worked fine. I will caution that in that application, and perhaps in some other application of your own, the edge of the diamond plate sticks out a bit over the plastic backing and furthermore the very edge has diamonds on it. Thus the edge will tend to cut into anything that it's rubbed against. That would have been a problem for me so I filed the diamonds off of the edge using another (not too precious) diamond plate. It was sort of a contest as to which diamond tool would lose it's diamonds first but before too long I had rid the edge of this tool of diamonds and I could use it on my saw without damaging the teeth that I had just sharpened.