This is a guide for drilling holes in 2020 aluminum extrusion. It has holes at 10mm intervals from 10mm to 100mm.

It is useful primarily as a layout and marking tool, obviously PETG is not going to keep a steel drill bit from wandering.

There are three sets of hole guides:

• 4mm - for a center punch to mark for holes
• 6mm - for drilling holes for M6 screws
• 11mm - for drilling holes to counter sink the heads of socket head M6 screws