Thanks for sharing your family treasures, Dave.
Regarding the grooves, Jim Hamm has a good discussion of it in "Bow and Arrows of the Native Americans." Having made hundreds of arrows the traditional way, Hamm found that if he grooved the shaft prior to heating hardening, it greatly increased the wood surface available to be hardened, making for much straighter arrows. The grooving is easily and quickly accomplished with a grooving tool -- a four-inch section of limb or dowel maybe an inch in diameter with a shallow, vee-shaped groove in the center and perpendicular to the axis of the dowel. At the apex of the groove a nail or a piece of flint is set. With the arrow shaft lying on a flat surface, you just align the shallow groove with the arrow and pull it down the shaft. I don't know if this makes sense, but it is a very simple process.
As to the hide scraper, I have seen these made as well from a short section of ruined musket or fusil barrel with one end hammered flat and then folded over at 90 degrees to form the scraping surface.