Collet for knife

A set of modeling knives has been lying around for a long time. Everyone has a broken collet in the thread area. Most likely from diligence, I wanted to squeeze it tighter. Then I bought it with a metal collet. And now, when various knives were needed, hands reached the repair. I made models with thread M5 for a small knife type 11 and M6 for large knives.
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Upd! I removed the holes inside the thread (they were under a thin self-tapping screw 1.6, like an anchor) - it was not required. And also made a thrust wall for the upper edge of the blade in the case of Type-1 and two thrust walls for Type-2. Now the blades don't hang out.