Put a miter on a rectangular tube

Open the rectangular-tube part from the earlier guide and check its dimensions, units and material. A simple part is best here, so you can see exactly what the miter changes. Left and right refer to the part's named ends, not the left and right of your screen; rotate the view and look at the solid rather than assuming.

In Quick Features, open Left End Condition or Right End Condition and choose Miter. The menu is filtered for the current stock shape: Miter is the treatment for non-round sections, and round pipe uses the separate Miter Pipe command. If that end already has a shaped treatment, a dialog offers Replace All, Add or Cancel. Replace All clears the end's existing treatments before adding this one; Add keeps them and puts the new miter after them; Cancel leaves things as they were. For this first exercise, start on an end with no other shaped treatments.

Select the miter in the design tree to open Miter End Condition. On rectangular tube, Plane offers Top and Front. Pick the plane for the cut you want, then look at the solid. Changing the plane also resets the suggested Miter Height to the matching cross-section dimension, so check it again. Angle must be more than 0 and less than 90 degrees; type it and leave the field to apply it. An out-of-range angle snaps back to the previous value. Miter Height is the span of the wedge across the section, not the tube's wall thickness. Keep the positive height suggested for the plane for now, and inspect the whole end rather than judging from one edge.

Flip Origin changes which edge the miter is measured from on the same named end. Check the slope in the model after you flip it. It doesn't move the miter to the other end and it doesn't set a machine work offset.

The parent end node has End Prep controls, including Normalize End and Bevel. Those apply to the whole end, across all its treatments. Leave them off for this exercise. Adding or replacing an end treatment clears the end's existing Normalize End and Bevel choices, so when you prepare a more advanced end later, set them deliberately after the treatments are in place. A sloping end on screen doesn't by itself give you a torch angle, an attachment or a posted cutting program.

Suppress keeps the miter in the part but leaves its cut out of the geometry; turn it off again to bring the cut back. Delete End Condition on the miter's tree row removes that one treatment. Delete All on the parent end node clears every treatment on that end. Straight Cut is also a whole-end reset: choosing it clears that end's treatment stack rather than adding another cut or hiding the selected miter, so don't use it as a visibility switch. When the last treatment is deleted, the end gets a Straight Cut entry. None of these deletes the part. When you're happy, save the part as a .gcmprt and check the end after reopening. Adding a miter doesn't create its cutting operation, choose a post, export G-code or update a posted companion file; that all happens in the part's operations and setup, and a linear stock job still needs the part's correctly posted companion program.