FYI
Small fans are readily available in old appliances if you have access to non-working refrigerators, upright freezers, or microwave ovens. Egg turner motors from the ice maker or microwave turntables , etc.
Probably a SEARS Super Hatcher. I've got one that I have had since 1973. It is a good incubator if you don't mind turning by hand. The slides in the bottom of the trays never seemed to turn the eggs enough to satisfy me.
The best thing to do for a broody hen is leave her alone. Feed & water should be in its usual place so she will know where it is and come off the nest to get it. This will let her get exercise that she needs and will help with the egg turning. She won't starve. Let nature take its course. This...
I have done this with good results many times. Eggs can still be good for several days if left in the nest if conditions are right. Duck nests are often on the ground and under something. The duck will also cover the nest with feathers or straw or whatever is available before she leaves the...
It is OK to clean hatching eggs if it is done properly. NEVER wash them. They can be wiped with a dry cloth or steel scouring pad. Do not use any liquids or chemicals. Don't worry about the stains, just the fecal matter. Rule of thumb; if you cannot feel the dirt, it won't hurt.