As a new user I can’t upload a short video clip so I hope the image and my description help explain this issue accurately…
I have extruded a flat ring, 3mm thick, 200mm outer diameter, 190mm inner diameter (imagine a giant 1euro coin but with the centre disc missing), on the front plane.
Using the centre point of this ring, I create a plane perpendicular to the ring, so that the plane dissects the ring (think of it as a plane offset from the top plane by 100mm). On this plane, I sketch a circle that is 5mm smaller than the diameter of the outer edge of the original ring. My intention is to cut a small slot / keyway of 2mm through the ring, at its middle, using this perpendicular sketch.
Going back to an almost front plane view, I highlight this sketch and pull it upwards by 1mm, cutting away (subtracting) a slot from upper half of the original ring. That’s what I want, well, half of what I want….
Since Shapr3D doesn’t have a ‘from mid-plane’ function, and considering I want this to be a 2mm keyway, symmetric by 1mm from either side of the middle of the disc, I assume I’d then need to re-highlight the sketch and drag it downwards by 1mm, subtracting material from the lower half of the ring and leaving me with a 2mm total slot removed from the disc.
However, this will not work. Using the mode select icon, I try ‘new body’, it adds a new 1mm disc perpendicular to the ring, but using ‘subtract’ it will not subtract from the ring. The program stalls for a second as if it is working on it, but nothing changes. I tried swapping the order of which way I pull the sketch and it will subtract in either direction, but not both, as in, I can only subtract in one direction and do nothing in the other.
This seems like a very basic thing to achieve and I’m pretty sure the approach logic is sound but it won’t work. A ‘from mid-plane’ function would do this no problem. Despite it being a bit annoying / cumbersome (requiring the extra steps of replicating what a ‘from mid-plane’ would achieve, by repeating the cut/extrude on the other side of the plane) I can live with not having it, but now this as really confused me.
Any help would be great, thank you!