MHP success!! After a harrowing 5 hours this morning, our batch of 23 chicks that arrived in the mail this morning are happy little campers!
To make my MHP, I used a wire shelf that was 24" x 30", and attached two of the large sunbeam heating pads to the bottom of it. I decided to use 2 since I wasn't sure my order of 25 chicks would all fit under 1. After that was done, I used bolts and washers and nuts to make adjustable feet on it. Turned it all on and tested it yesterday, looked great! Added a piece of leftover vinyl flooring to the top to protect the top of the heating pads from poop.
This morning, it took a chick about 0.2 seconds to get itself wedged between the heating pad and the wire shelf....since the heating pads are under the shelf, and the shelf has a pretty good lip on it, no idea how that happened...so modification #1 -- I put duct tape around the edges of the heating pads.
Half hour later, I pull the vinyl flooring up to verify no one else is caught between the wire and the pads, and a chick has his head stuck between the two pads where they come together. Modification #2 ensues...duct tape where the two pads come together.
Back to work for awhile, where I keep

and debating what the odds are of a chick getting their head stuck between the pads and the bungee cords. Decide I can't deal with worrying about that all the time while I'm working, so over my lunch hour modification #3 occurs - remove the bolt legs, wrap the whole thing in a large sheet, and fasten every single opening with duct tape... Then put the bolt legs back on by creating a tiny hole through the sheet where the legs go.
Everyone is happy and loving it now, and I'm reasonably sure they aren't going to kill themselves on MHP.
First iteration:
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Current iteration: wrapped in a sheet
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And some cute pics from underneath:
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