I was hoping that for a brooder I could get one of those big plastic storage bins, cut out the majority of the lid, and cover the opening in hardware cloth. I really need something cat proof, as my cat is an avid hunter of chipmunks and small birds. When is it ok to start holding them, aside from moving them into the brooder/under the heat plate?
We use the big CLEAR plastic storage totes for our brooders, right beside my little's chair in the living room. I did originally do the top as you were saying,(that would work great to keep cats out). However that didn't last long as the little needed to hold and cuddle her babies multiple times a day from the second they came out of the incubator. Especially before she went to bed. Holding and cuddling them from the second they leave the incubator/arrive at the Post office is perfectly fine. It keeps them warm in your hands and you can more easily realize when something isn't quiet right.
I found early on that I NEEDED clear totes. So I could see what was going on in there from across the room, it's hard to resist checking out those cute little chirps, instead of doing other chores. I would never get anything done if I had to constantly go over and look down on them. I like to see from the sides on their level what they are doing.
This year I got 2 different sized clear totes, the first was the shortest and longest I could find. Ended up with one you roll under the bed. It even has a flip top so that half of it can be closed at all times and the other half is folded back on it. I have the heat plate and feeder in there and then the nipple waterers that sits on top of the heat plate for less mess. They catch on instantly, the first time you show them how to use it and nothing gets in the water.
I got a second normal height clear tote for when they started getting big enough for them to jump out. When that happens they move down to this tote so they can't as easily fly out. (short one is on a table). We incubate with weekly hatches right now, so when a new batch hatches, the previous hatch (if we don't sell them first) move down and by the next week they are outside. We raise bantam and full size, we try to keep them together by size rather than age. The seramas are now 6 weeks old and feathering out but are still in the smallest tote. My little loves always having babies beside her, although she has her favorites of the grown and teen ones.
I used to coddle my babies until they were 8-12 weeks old in the house until we had a hen go broody and watched those teeny tiny babies rule the barn yard. I'm sure they thought they were scaring everyone away, but they had no fears and would wonder through the fence and away from their parents only to be hollered at to come back. They were SOOOO cute with the big ones at only a day old (and older of course). While I had big 8 -12 week old babies that had never touched grass..... I put them outside sooner when it is warmer, like within 2 - 3 weeks, in a chicken tractor away from the bigger animals, since they don't have a mommy to holler for them to come back at every second. I have a heat plate in there for them. If it is early spring we will sometimes bring them back in at night if it's going to get real cold, more because my little is worried about them than that they are in real danger.