In Kiko Denzers book he suggests incorporating a hearth tongue protruding over the edge of your base to help with sweeping out the ash etc.
I am thinking of doing this using 25mm fire bricks for the tongue, but as the front of my base is a wooden sleeper I was wondering how hot these bricks at the very front are likely to get, and will they burn the sleeper they rest on?
I think they'll certainly get hot enough to char the wood, if not actually ignite it so I'd be a bit careful. Maybe rebate a little insulating board into the area concerned then cover it with your tongue? .