This is an adjustable and ergonomically pleasant chamfer plane using a standard 61 x 19 mm trapezoidal blade as e.g. available from Stanley (TM). You may adjust the cutting depth by moving the knife up or down its two mounting slots before tightening the screws.

The relatively shallow cutting angle of 30 degrees is best suited for soft wood (e.g. spruce). The marginal thickness of the blade (0.6 mm) does not allow for much steeper angles which would be more appropriate for hardwood.

Inspired by
https://www.thingiverse.com/thing:5317986
but completely redesigned.