Good question. If you make a mistake or need to adjust a bend angle, you can adjust the bend or try again - no problem. After 5 or 6 bends, though, the metal will fatigue.
The holes for the perch closely match the perch dowel for a snug fit. You can increase the 'friction' on the dowel by tweeting the angle of the front and/or rear panels!
In our part of the world, the birds go crazy for sunflower seeds!
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