Offsets in Onshape

lougallo

When sketching in Onshape, you can utilize the additive selection (no CTRL key needed) and select the entities you would like to offset and click the offset too or hit 'o'. Setting direction and magnitude is pretty straight forward. If you select a planar face you can offset all the edges of that face.


Pro Tip:
If you have connected entities and want to offset all of them, click on the Offset icon (o) and the click and drag off one of the entities and you will get all the connected entities in one shot. See examples:

Open contour:


Closed contour:


Have you noticed this behavior?

Ben_

NICE!

josh_levine445

I can't seem to get this to work. I think I am following the exact steps above - create a sketch on face of a part, click offset, try to drag arrow. When I try to offset, I get a message at the top of the screen saying "Offset could not be created at this distance." What am I doing wrong? Thanks!

shanshan

josh_levine445  this information just means this surface can not be offset with the default value "5", you can ignore it and drag the arrow to change the offset value !

Narayan_K

@ josh_levine445 ,It looks like offset not able to generate for the given offset value .Try with less offset value.if not,as a work around you can select all the edges one by one.

josh_levine445

I would have thought that any curve could be outset by any distance form 0-infinity. What are limitations for an offset? Thanks!

robert_morris

@josh_levine445,
A single curve can be offset to infinity, but with multiple connected curves there can be issues.

The problem is occurring at the inside corners of the part in your screenshot. As you offset those curves beyond a certain distance, eventually one or more of those curves ends up getting reduced to a zero length by the curves next to it. You can see this if you slowly drag the arrow closer to and then away from the part.

Onshape doesn't currently like having those curve segments being changed to zero like that. I know SolidWorks had issues with that as well.

If you want it to be offset beyond that point, you will have to offset the edges in smaller groups and then trim them manually where any of the curves intersect. Something like this quick example:

jakeramsley

josh_levine445 said:

I would have thought that any curve could be outset by any distance form 0-infinity. What are limitations for an offset? Thanks!

It looks like the shape you are offsetting is a spline and not a combination of lines/arcs.  A spline cannot loop in on itself or self-intersect which is likely to happen given some of the concave parts of it.

fastwayjim

Onshape does not seem to be able to offset multiple closed contours in a single sketch. Is this true, or am I doing something wrong?

robert_morris

In a single sketch, yes. You just can't select them both at the same time.

In other words, offset one close closed contour and enter in the dimension, then offset another contour and enter in the dimension for that one next.