So, a new(for me) backsaw arrived this week the result of yet another trip to eBay. It's in pretty good shape but it needs sharpening. My eyes have never been my strongest asset and now in my late fifties they are worse than ever. Any thing smaller than 10tpi I cannot see clearly, I've been thinking of using a watchmakers loupe,anyone got a better idea and if you have gone down this road what magnification proved useful.