Using a fixture plate precision hole pattern to locate irregular shapes.

[Mook]

This part is asymmetric, with no straight edges for reference points. The challenge is to cut a pocket, 1.5mm deep, exactly 12mm in from the perimeter.
To solve this, I first created a template. That let me work out three reliable locating points around the perimeter. I then marked three holes to give a repeatable position for the part. In CAD, I overlaid the part shape, making sure the perimeter touched all three pins. That setup will make programming the pocket much easier later on. Programming the pocket used dimensions from the CAD file using the centre hole as a datum.

[DIYer]

Thanks Mook! We've added your Irregular Shape Pocket Cutting Method to our Machining category,
as well as to your builder page: Mook's Homemade Tools. Your receipt:

Irregular Shape Pocket Cutting Method by Mook

tags: fixture, CAD