I've never done that, but that's an awesome setup. I have 4 silkies fighting over 3 boxes right now. That would be perfect.Hatching Hens are No Problem and No worry for me. If I had enough of them going broody I would sell my Incubators. Last season I had 33 sets----some hens went broody 2/3 times during the season. Over 250 chicks hatched, I do not remember not one fertile egg that did not hatch, and every egg hatched usually in a 24/30 hr time period. No hen left any unhatched fertile egg(I do not candle their eggs for fertility till after they leave the nest).
Set your Hens just Like you would your Incubator----collect and set all fresh eggs under the broody at the same time, just like you would your incubator. DON'T add eggs or allow eggs to be added after the set day to your incubator or broody. This means for a broody----you either got to mark all the set eggs and remove any fresh layed eggs daily OR move your broody to a private place or fix her nest where no other hens can get into the nest.
Here is the way I look at it------we can go spend $100 + on a incubator and turner-----why not invest Less than that to make a broody pen---then when you get a broody---place her in the broody pen(properly)-----she will automatically turn the eggs, keep the temp and the humidity perfect through-out the whole 21 days----A Perfect incubator----not a worry in the world. Here is one of my broody pens----cost less than $100 to make----will house 4 broodies at the same time, but separately..
Great, something else to build