# How to cut out an access path for a 3D object?

What is the best way to cutout an access path for a solid in a second solid?
En example would be to make a cavity for a nut with rear access?
The bottom of the cavity would be identical to what can be produced with BooleanDifference, but the access path would need to be removed as well.

Hi -
The âbestâ way might be dependent on the specific situation. Generally, youâll have to model the surfaces of the access path. As a slot for an embedded nut, that might be a low cylinder that you boolean together with a box that sticks out of the overall object. Then use that new object to cut the part that you are modeling.
-wim

I am assuming the access path is straight and perpendicular to a Cplane. If the access path is not perpendicular to a Cplane create a Cplane perpendicular to the access path.

In the view with Cplane which is perpendicular to the access direction run the Silhouette command with InternalEdges=No. Join the results into a single polycurve.

Copy the solid in the desired location. Split (not BooleanSplit) the copy of the solid using the the silhouette curve.

Copy the silhouette curve in place.

Move the open surface which does not stay in place and one silhouette curve in the direction of the access path outside of the second solid.

Start the Loft command and select the two silhouette curves. Check and adjust the line for the seam of the loft if needed. It must be between same points on the two curves. Complete the loft command

Join the loft command and the two open surfaces into a closed polysurface. This polysurface surface will be used to create the access path.

BooleanDifference the second solid with the access path solid.

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Well, not necessarily - there needs to be a minimum of an allowance for tolerance and, generally, rather larger access for tooling.

Thank you! Very well explained, general solution that will likely work even with complex shapes and that does exactly what I wanted.

The intention was to conform the cavity to the shape of the nut, so that it will not rotate when the bolt is screwed in. Though possible with a hexagonal âcylinderâ as you describe, it does require manual modelling which would be complex for complex shapes (like, eg, a rounded hexagonal nut if one would want to have it 100% right).