I was just going to buy a flat piece of sheet metal at Home Depot, but then I ran into this thing.
Apparently this is a storm collar.. You’ll also need some tin snips to cut the metal. If you can’t find some in the toolbox of your husband/dad/neighbor then you can buy them for about $10, too. Go get some now, because I have more uses for them coming up soon.
Cut off the part of the collar that has the metal brackets welded to it. Then CAREFULLY put the collar on and start gently shaping it by bending the metal with your hands.
Flip the collar over and use a Sharpie to draw on the underside where you want to cut away the extra metal. I didn’t do any measuring or break out the compass – a rough sketch will do. I made it the full width at the center and a little less than half the original width at the back. Mark some dots in between and then connect them with an arc.
Cut it out along the line. To make the cutting easier, bend away the metal you are removing as you cut to allow your tin snips to more easily follow the arc that you’ve drawn. If you continue to cut in a long line (instead of starting and stopping several times) you are less likely to have lots of sharp pokey bits along the edge. I bought a file to smooth the edges but didn’t even need it. Finally, use the tin snips to round the back edges to remove the sharp corners.
Seriously, removing the glue from the UPC sticker was the hardest part of this DIY!