How long does it take to make a good campfire?

Depends how big a fire you want, how dry your wood is, what kind of wood you're burning, and if you're any good at building fires. I'd say half an hour is good, uming you have more wood besides what you've already set up in the teepee shape in case it burns fast. The key to roasting things on a fire is that you need to let the fire burn down to mostly coals. Once it has done that, it's as hot as it's going to be and that's what you want for roasting.