Making this type of hide scraper is easy. First score around the edge of a reindeer/caribou "skovle" (what we call the flat pieces of the antler here). Brek off the irregular front and then score along the sides. As usual, using hot water will help you a lot. Split the piece along it's lenght. Tidy it up and make the lower edge sharp.
This type of scraper is quite effective, but the width is too large for my strength at least. Adding a long handle to it would make it better of course, since you then could put a lot of weight into it. It is used with a chopping motion, or by forcing the corners under though points. These scrapers were used to scrape both the flesh and hair side of the skin of the new coracle/currach/bullboat I've been making for the museum. A post about that will hopefully be up within very few days.