What are the best materials to use
Welcome to the Bunnings Workshop community. It's marvellous to have you join us and thank you for sharing your question about building a budgie breeding cage with a breeding box.
What a fantastic project to be undertaking. If the cage is staying under cover, I suggest using plywood in combination with dowels, standard pine and steel mesh. Have you decided how big the cage would be? Do you want to have easy access to the breeding box itself?
If you've not yet decided on the size, I propose a minimum size of 700mm wide x 600mm high x 500mm deep. The breeding box can be 250mm in length width and height and positioned in the upper right-hand corner of the cage itself. The dowels will need to be positioned near the breeding box their bird feeder and water dispenser.
You can either use screws or nails to assemble the cage, my only reminder is to make sure to build a pullout waste catching box at the bottom. If you have a plan in mind, I suggest drawing it up on paper and sharing it with the community.
If you have any other questions we can help with, please let us know.
Id also like to say welcome to the community There are so many ideas in here its not funny!
I remember my family having an avery and breeding boxes when we were teenagers. (Take a guess who had to clean them out!)
I can remember thinking we should have built things different over the years of cleaning the cage as the cage deteriorated.
-Use timber suitable for outside (H4 and above)
-Drainage for cleaning out the cage.
-A double roof if its outside. Summer would hammer the roof and heat up the open avery like crazy. We would put old potato sacks and hose them on the roof but they would dry fast and also cause drainage issues.
Timber, small mesh that wont be chewable by whatever potential birds you have (larger then a buddgie) and a waterproof roof plus a concrete slopped bottom with no ability for water to pool against timber in answer to your question
-Make sure that the mesh you use is on the "inside" of the posts, if its on the outside then those lovely birds do like to chew
-Breading boxes I cant remember too much other then they were placed high and not to disturb them by "looking" into them frequently.