You’d think that hatching chicks from eggs would be easy – after all, birds do it. But it turns out to be a fussy business for humans, and what momma bird does naturally isn’t necessarily easy for us.

If you want to keep eggs warm to hatch, you’ll need an incubator. You could buy one off the shelf, but they’re not so complex — just a nicely-controlled warm box you could easily whip up yourself. As ...