Russian flat-cutter or ploskorez Fokina (Fokin hoe) needs to be sharpened often for comfortable and effective work.
Sandstone sharpener is a good and handy tool to sharpen a flat-cutter or any other garden tool like hoe, scythe or kitchen knifes.
And wooden handle will make the sharpening process more comfortable and protect your hand from cuts.
For sharpening tips please watch the video: https://youtu.be/MkWMM_Q25Uk
More info about ploskorez Fokina here: https://ecominded.net/fokin-ploskorez