How do I turn a toolpath preview into a 3D component, and why is the option grayed out?

What it does

Create Component from Toolpath Preview (Model menu) takes the current toolpath preview and converts it into a component. The new component is added to the Component List with the name Toolpath Preview. The official documentation gives two main uses:

• finding areas that were not machined, so a smaller tool can be sent to just those spots,
• building shapes that only exist because of the tool, such as fluted veins on a leaf or a texture toolpath, into the 3D model.

Educators also use it to preview glued-up or laminated looks: turn the preview into a component, then give it a realistic wood material.

Steps

1. Calculate the toolpaths and run the preview so the 3D view shows the result you want to capture.
2. Choose Model > Create Component from Toolpath Preview.
3. Optional keys held while you choose the command:

• Shift: preview areas that lie over transparent parts of the composite model are discarded. You get only the region of the original 3D model, without the surrounding waste block.
• Ctrl: the component is the difference between the composite model and the preview. It looks odd, because it is only the material the finishing tool's radius left behind. Use it to draw vectors that limit a detail pass with a smaller bit.

If the part was fully cut out and Delete Waste Material was used in the preview, only the pieces left on screen become the component. Otherwise the whole preview block is converted, scrap included.

If the option is grayed out

1. Make sure the toolpath preview is actually visible in the 3D view.
2. On a two-sided job, switch to the single side view instead of the multi-sided view.
3. If it is still unavailable, save the file, close it and open it again.

Pro tips

• The documentation notes the command only makes sense while the preview is active in the 3D view, so the component matches what you see.
• The Ctrl version pairs well with a vector boundary: trace the leftover areas and run a second finish pass only there, which saves hours compared with running a tiny bit over the whole model.
• See the entries on speeding up 3D carvings and on rest machining.