As you guys already know...one of the great things about the saw blade is its sharp spine. The spine makes a great little scraper and fire steel (ferrocerium rod) striker. I use mine to scrape off those annoying stickers that seem to come on everything. The 90º spine is usually pretty sharp, with a fine burr on it. This makes it work a bit like a bench scraper. (albeit one with some sharp teeth sticking out of the top....)However, like awl things that get used, the spine needs to be resharpened. Preferably back to a perfect 90º. I'm curious to know how you guys sharpen the spine of your SAK saws....without damaging the teeth of the saw itself, or your hand, for that matter.I think I need to up my game here. Right now I just freehand the spine with a mill file and then hone it with a smooth steel designed to roll the burr over. (Same way I do for a bench scraper.) Sometimes I become more ambitious and use a diamond plate. But, I think I could do better and I'm looking for more reliable methods. I have a few ideas, but am interested in what other SAK knights have found helpful. Please share your saw sharpening technique!
On a flat surface. No angle. Hard sharpening stone. Wet/dry sandpaper taped to a sheet of glass maybe. Make sense?
Maybe you don't want to modify all your saws into Felix Imler specials? Just smooth out the burr created by filing spine. Marcellus
Not at awl... I want that burr! The burr is essential for a scraper (in this case saw spine). It's the burr that does the cutting. That's why I used a honing rod after sharpening: to curl the burr over and harden it. As a scraper is used, the burr can become folded back. Often just honing a burr with a slick metal rod or piece of glass can roll the burr back to 90º or better and get the scraper working again. The first step for me when a saw spine (or bench scraper) seems less than aggressive in cutting (while scraping) is to hone the spine with a rod or smooth piece or round glass. Here is my honing rod and a plain steel rod that seems to work fairly well, too:(Image removed from quote.)OK, seems like you're all set. I wasn't sure all what you wanted your saw to do. I suspect hand sharpening the saw spine with a diamond file would work well for you.
I suspect hand sharpening the saw spine with a diamond file would work well for you.
Thanks. I'm thinking about way to make a jig. Or to use my vise in a jig-like manner. I feel pretty confident freehand sharpening a knife edge, but I have found that it can be a bit trickier to precisely sharpen a saw spine or bench scraper to 90º...with a decent burr. On a knife edge, I don't want a burr....right? Just a clean cutting edge. But...as you and Felix note....the burr on the spine is a real asset.