I tried it, years ago, didn't work too well...There is too much pressure and the patches burn through as well, accuracy was not good....You can have any size mold made that you want, just contact one of the custom mold makers...
Are you saying the .490s are too tight with pillow ticking or denim??? If so, I would work on different patching material...When the wife goes to fabric shops, I'm always looking for something different, may even run into some linen, that works well too...