wally on our bedroom radiator
Wally on some fabric scraps on the dining room radiator
Step 1. Gather Materials
Since this is a gift for cats at a pricey time of year, my goal is to use as many leftovers and existing materials as possible. So I start in the wood pile and find a 1"x8" that's exactly long enough for the radiator to serve as the top, and some 1"x2"s to serve as the sides. I have spare fabric that used to be the curtains in the old office that will work perfectly, so it just gets washed (ironically, to reduce the cat hair). For the padding, I turn to Amazon and buy some 1" upholstery foam and batting and silicone oven pads/trivets.
Step 2. Assemble Frame and Top
First, I cut the 1x8 down to be just slightly longer than the radiator's widest points. Then I cut 2 1"x2"s to be the same length as the top, and 2 1"x2"s to span the distance from the outside of the 1"x2"s and the board. Then, using wood glue and some wood screws, I screw it together so that the 1"x2"s cap the board and are flush on top. They will prevent the board from sliding around on the radiator. This will all be covered, so ugliness isn't important.
cutting down the boards
test fitting on the radiator - everything fits
Step 3. Upholster
I cut down the foam pad to the same measurement as the frame and glue it down. (Note - you're generally supposed to use spray upholstery glue, but I didn't want to buy any. Instead, I used an old glue stick). I wrapped the pad in a thin layer of the batting, which is just meant to smooth out the pokey edges of the pad and stapled it down. Then I draped it in the fabric, flipped it over, and started stapling like crazy. The hardest part of this part was keeping Wally away - as fabric on the floor is basically his favorite thing.
1" pad on top of the board
wrapping in batting (find the cat in this picture)
batting all stapled down
fabric stapled down
Step 4. Heat proof
Once I was all finished with the fabric, I flipped it upside down and stapled on two silicone oven mit things. The goal here is both to reduce the risk of a fire by preventing the wood and fabric from resting on the hot radiator all the time (they don't get that hot, but it seems like a good safety precaution), and to prevent the box from sliding around on or rocking on the radiator every time Wally jumps on it.
an oven pad getting stapled to the underside of the bench
Step 5. Enjoy
After everything was finished, I placed it up on the radiator and set Wally up on it. He was a little uneasy at first, and then seemed to get the hang of it. I think the first Christmas gift of the year is a hit. This was totally an unnecessary project, but it only took a couple hours and like $20 - so I'm pretty satisfied with it.
check out the nice corners
Wally takes a nap