How to sharpen a benriner mandoline blade
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It's probably cheaper to buy a whole new mandolin than the replacement blades, btw. My coarse blades are all but shot. Can't sharpen those. Flat blades go for around $10 -15.
There are a lot of very smart bladeheads here. Have some patience; someone will chime in. My humble advice :
I let the blade angle guide me and do it by hand on water stones. I have a jewel magnifier, and inspect the blades insuring a flat even surface.
Don't forget about removing burr on the opposite side.
I've not seen nor heard of this mentioned here by bladeheads. Not everybody uses it. I do simply to double check my angles and make sure I've removed enough material. Not very scientific or precise. Just an observational tool.