I use Style D and E brazed ceramic lathe tools, as well hand ground HSS tool bits on my lathes for chamfering operations. The problem is the lack of clearance with all these tools if you want to chamfer the inside edge of a hole drilled using the lathe, especially if it's a small bore.
So I was searching on the internet for a tool that I could purchase, when I hit on this guys web site.
I procured some HSS 9.5mm blanks from eBay. I used the side of my surface grinder wheel to put the 45 degree point (90 degree included angle).
I used the 5C spin indexer for this operation;
Pretty much I used the same process to grind the cutting edge to the HSS blank using a 5C square block, this ensures both ground cutters are in the same plane so when installed in the quick change holder, I can rotate to square to the work or parallel to the spindle;
I use the 400 and 100 series of quick change tool holders between my small and large lathe so I made 2 of these chamfer cutting tool bits.
I'm very pleased with how these work.