I have a female rat. She is still a "baby" I guess. She doesn't chew at all on anything besides her treats and things. But, if your rats keep escaping I have a question for you. Are your rats females or males? Females are more prone to escaping and males just like to hang out. This is because females' instincts are to look for food. We had to change our rat's cage because the wires were too thick and she could squeeze through them. We've had no more problems with her getting out since.