Hi Forresdweller
I am currently trying to master this also and was going to post my own question but I thought it might be ok to tell you what I know and get help at the same time.
not trying to take over your thread
I have been using what I think is hazel (its dead wood and may be mixed ?) and all the wood I am using is from one branch including the bow.
the annoying thing is I am getting a small ember and lots of black dust but in the bearing block !!
the larger flatter end is just going a shiny brown and producing no dust yet the smaller bearing end is burning !??
I have had embers drop on my finger I would just turn it over but the bearing block is about 2" thick
so the wood seems fine I just need to know what I am doing wrong ?
Ideally the bearing block should be a lot harder, but my first bowdrill ember came from a hazel on hazel set using a soft pine bearing block ( ! ) but then the recess was packed with castrol LM grease - i wasn't taking any chances
I had the bottom of the drill glaze over a few times too - there's a couple of ways of dealing with that - either roughen both hearth and drill surfaces with coarse sandpaper or make a series of tiny radial cuts with your knife before starting. The bearing end needs to be quite pointy and very smooth.
Another problem I came across was the drill jumping out of the hearth (usually out of the notch). This was caused (in my case) by either the notch being too deep or the board not being flat and therefore drilling at an angle.
I'm only just near Chester so depending where you are, you're welcome to come over for a play with it if you want to compare notes?
Best of luck,
Dom.