You are saying you want that hex bolt head showing, am I right?
Thanks for all of the responses.
No the hex head wont show - I'm the only one that will know how sloppy they are.
Was simply wondering how to do the job better, am fairly sure that others would do a much tidier job than what I have done. The post was basically a "fishing trip" to initiate some discussion and find out how others approach this sort of job. ie make a clean blind excavation of a specific shape in some timber and put in a tight fitting metal insert.
If I go slow and careful with a narrow sharp chisel it looks ok but its fairly easy to slightly overcut one edge and on such a small hole even a little mistake is a big %age of the hole size and just looks ugly
FYI on another thread somebody recommended this parser tool Two Legged Parser
I thought the funny hex drill bit in the video I found is an amazing and interesting bit of gear
Metalworkers have tools called broaches that seem to do this sort of shaped blind hole very well.
I wasn't sure about how well epoxy would grip a bare threaded bar and I will give that a shot .
Thanks again for all of the various responses.