Thank you for commenting on my blog - I was in the same boat - do I buy a new can opener. But I like my "Large-Handle Kitchenaid."
It is a bit tricky to run the sandpaper through the canopener but it can be done if you take your time. I didn't try the foil as I had sandpaper in my hand, lol. I found that it is easier to start at the top because when you turn the handle in a clockwise manner, it goes down the paper. I know, it sounds confusing but when I tried from the bottom I got nowhere real fast.
Good luck with your chosen program! It takes time but you are worth the extra effort it takes to get healthier.