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The slitting process requires the tool to pierce material securely and accurately while overcoming various side loads. Parting a sheet includes an amount of punch overlap in each hit where sheet resistance is partially absent. This causes the punch to try and move towards the space where material is absent. The greater the area where material is absent, the greater the side load on the punch. In extreme cases where sheet thickness is thin, the material may even be folded into the die rather than fracturing and falling away. Any of these problems can reduce sheet quality.