I’ve been using Rhino for a few years on a low level, but I have never had this happen before. I extruded two curves straight up at a 90-degree angle in the Front view. Then I tried to make a boolean union but it keeps showing an error. When I zoom into the top right corner it shows a line of the extrusion shoots our past the edge of the extrusion surface wall. Please see the picture.
Is this why the boolean union won’t work? Why is my Rhino 6 doing this?
Boolean Union and most of the other Boolean commands almost always yield funky results. Is there another way to achieve what you are doing without using Boolean Union?
How far have you zoomed in? Can you use Distance to measure the length from the end of the line to the corner of the extrusion. My guess is you have zoomed to a very high magnification and what you are seeing is the limitations of the display calculations, not a problem with the actual geometry.