kiwi, keep using the Norton India stone you found of your Father's. That is what I use and it works great. It sounds like you haven't fully apexed the edge and have left a burr. The manner I work that stone is, use the coarse side with mineral oil and take the stone to the ax. Work one side until you feel a burr on the opposite side. Then Change sides and work that side until you feel a burr on the other side, remove the burr.
Then switch to the fine stone and do the same. That stone is 150 grit coarse side and 400 grit on the fine side. Here's a picture that shows the manner I use the stone. When using the coarse stone I rub in both directions, back and forth. When finishing with the fine stone I rub into the edge only. Use less pressure with the fine. DM