No problems John.
Here is a quick C-o-C to show you the tool in graphical format (getting technical words now as well).
The first one is showing the 1/4 round, second is the back rake and the third would be classed as bottom rake.
You actually grind 1 & 3 at the same time, then put 2 on last.
Number 4 is how you finally put a razor edge on the tool. I use an Arkansas stone with oil, but you could use a diamond lap with water to stop it clogging, or just a fine emery stone with a touch of oil. This is also how you touch it up during use.
If you ever have a go at some real tough stuff, you will most probably end up with a flat on your main radius. In that situation you have to do the 1 - 3 regrind to get the curve back.
The angles are non critical, but I put a fairly large one on so that it can easily cope with a range of materials. In fact, if you were cutting brass all the time, you could do away with #2 (back rake) completely.
What I have done this morning is go into the shop and ground one up to show you a close up of the finished article.
It was a little dangerous trying to grind with my left hand, keeping one eye on the tool, and take a piccy using my other hand and eyeball. I know I am adaptable, but not that much. So what I have done is ground it up, and flatted out non essential bits with a black marker.
These pics are as they came off the wheel without final sharpening.
The radiused tip.
What I called the bottom rake.
The bottom rake viewed from the other (untouched) side.
And finally, the back rake viewed from the end.
Actually the bit marked top is really the forwards facing part of the cutter, I just marked it up that way to help with the grinding sequence. I just hope I haven't confused you all.
This is the way I grind for getting a good material removal plus nice surface finish. Just remember, start wacking this thru a bit of tough stuff, (I didn't really want to call it Darren's stuff), don't expect miracles.
Of course, flycutters have a myriad of other uses, and in those situations, they have different shaped tooling ground up.