Straightforward bracket to mount a 30mm fan by one corner screw. Fan points at a 45 degree angle.
Hole is meant to be exploited M3 Mounted 3 component cooling fans on the corners of the stage of my NEMESIS Air Delta Printer. Drawn with DesignSpark Mechanical. Source file that was drawing contained. This is an excellent simple to use FREE 3D CAd software, check it out at http://www.rs-online.com/designspark/electronics/eng/page/mechanical
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