Allow an override to the Sweep intersects itself error.

t_cary

When sweeping a spline that curves in and out there are times when creating a solid it is irrelevant that the same volume of space is redundantly defined.
I'm trying to sweep a coping around an irregular shaped pool.  When I sweep the perimeter every place it turns outwards causes the sweep to intersect itself. I want to disregard this.  I can work around it and make multiple paths and then do the boolean, but...  a check box to allow it... or why not simply allow it and give a warning?

lougallo

@t_cary self intersection creates bad geometry and in most cases that can be avoided with larger radii sweeps.  In some cases you might be able to get it to work with a surface but ideally the surface it creates is just going to have issues further down stream if there is overlap.  I would be happy to look at the case you have if you want to send in a ticket to my attention or post a link here and share it with our support group using the Share with Onshape Support slider.  Ticket is probably best tho.

aidan_fraser

Hi lougallo, I understand that we want to avoid bad geometry. I'm just wondering if there is any reasonable workaround for reasonable cases when the sweep intersects itself. Often increasing the sweep radius, or reducing the geometry of the swept shape can work, but that's often an unworkable compromise.

One common case I find quite a bit is trying to model a routed cut along a curved edge that has some radii/details that are smaller than the routed shape. I think it's a reasonable thing to _want_ to do, because it's pretty trivial to describe and manufacture.

Here on the right is a chamfer that's easy for onshape to handle. On the left the chamfer is at the edge of what is currently valid. I _often_ find myself wanting to go further than this. It seems easy to imagine a part that has been chamfered with a larger distance, and while there may be obvious mathematical/modelling reasons that this is difficult, as a user it _seems_ arbitrary that onshape rejects it.