I'm a little confused with the sharpening angles of crosscut saws.
Hi. After having sharpened 3 ripsaws I'm now delving into sharpening another 3 crosscut saws. I was thinking of 5, 7 and 9 TPI (would it be more appropriate to talk about PPI?) to have saws for coarse, medium and fine cutting and I wanted to sharpen them with the rake angles appropriate for the task, which I suppose should be different on each saw, since with the 5 TPI one what I want is to cut fast and with the 9 one I want a clean cut. I've seen the Blackburn Tools article with the attached table of sharpening angles, but I need to understand it all a little better. I understand that the lower the rake the faster it will cut, and the more fleam the cleaner, but I don't know how much fleam affects cutting speed and even less the implication of slope beyond creating a more resistant point. I also see that in the table the file angle that determines the rake should be less than the final actual rake of the tooth, although I don't understand why this is so. I work almost exclusively with hardwoods and I was trying to determine the 3 sharpening angles (rake, fleam, slope) that would be most convenient for my case. I know that a choice of angles chosen a bit by eye is going to work, but surely a well thought out one would be capable of better results and would help me understand this matter better.
P.S. is the file size for sharpening crosscut saws the same as for ripsaws?