Punch a hole in the middle of the paper cover where the hole of the spool is. Now your hole should run through the paper, spool, and cardboard without any obstructions.
在纸片棉线轴洞的位置打个洞，这个洞贯穿了纸片、棉线轴和硬纸板，洞内没有其他遮挡物。
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The PIN digits you punch into an ATM’s keypad are leaving traces of themselves behind in the form of heat, says a paper recently presented by a team of UC San Diego security researchers.