How much ventilation needed in a homemade incubator?

[xcalibor67]

This has been a very intimidating part of my bator build. Spent many late hours reading until my eyes hurt, trying to find that "Magical" number/equation to spell it out as to "How much ventilation" i needed for my bator. As having done HVAC for many yrs, i understood things like static pressures, CFM's, air exchange rates etc., but was never 100% satisfied with my set-up. The thing about fresh air exchange rates, humidity, etc. all goes back to the EXACT set-up you have..Infinite variables. How big your fresh air holes are, where they are placed, behind a fan? beside? etc.Does your unit even have a fan? There are honestly just so many slight differences that can change the outcome, ive decided the best bet is to look at your size of bator, and compare it to other peoples. Mine is about 16"x 17"x36" inside dimensions. with my set-up, i used 6=1/2" holes drilled where i thought best. In conclusion, there is no "Magic Number" anyone can give you. Just use your good judgement and dont over stress it..