circle cutter
thingiverse
Little helper to cut perfect circles. Additional parts required: Pin Exacto blade (https://www.amazon.com/Wedo-7821-Replacement-Blades-Hobby-Knife/dp/B000KT9C3W/ref=sr_1_1?ie=UTF8&qid=1474416355&sr=8-1&keywords=Wedo+7821) M3 bolt (minimum 6mm length)
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