Clamp the GEM against a used Feather with vice grips, then widen the half moon notches to match using a grind stone with a cheap rotary tool (dremel type). Makes a perfect fitting blade, just take your time, light pressure with the grinding stone. - I do half a dozen or so at a time, but have two boxes of 100 to work from. (You'll mess one up now and then, but as you get the process down, it becomes easier).
I tried a punch, and it broke/cracked off pieces of the blade or distorted the blade around the cut area, resulting in more destroyed/ruined blades than those that worked. Returned the punch, it just wasn't sharp enough, or at least the one I bought sure wasn't. - That's when I thought of using my little dremel, which is so much easier. I test fit in my Hybrid, to ensure they won't cut the stops off the Core. Just go easy, as you can always grind a bit more, but it's impossible to put material back, if you grind too much in the wrong direction.
I tried a punch, and it broke/cracked off pieces of the blade or distorted the blade around the cut area, resulting in more destroyed/ruined blades than those that worked. Returned the punch, it just wasn't sharp enough, or at least the one I bought sure wasn't. - That's when I thought of using my little dremel, which is so much easier. I test fit in my Hybrid, to ensure they won't cut the stops off the Core. Just go easy, as you can always grind a bit more, but it's impossible to put material back, if you grind too much in the wrong direction.