Extend one surface of polysurface

I have an object to which I want to add some extra ‘thickness’ on one side. If I explode the object then I can move one surface out to the new position. How do I extend the other two surface edges (without distorting the hole openings) and then turn it all back into a polysurface? Or is there another way to do it?

lol…I think it may be as simple as BooleanUnion!

Assuming BooleanUnion is an acceptable way to do this, is it the correct way when taking into consideration that this object will be exported from Rhino as a step file and submitted to a machine shop for manufacturing?




from the Solid Tools just use Extrude Face, to get rid of extra edges use Merge all coplanar faces. The commands are:

_ExtrudeSrf _Pause _DeleteInput=_Yes

Avoid to use Booleans with adjacent coplanar objects in general.


The ExtrudeSrf command (with DeleteInput=Yes) worked great. But what does MergeAllFaces do? The object appears fine after the extrusion.

You can also extrude from Gumball, select subObject with Ctrl + Shift , then move and holding down Ctrl to extrude.

MergeAllFaces merge all coplanar faces.

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Here’s info on the command :
MergeAllFaces | Rhino 3-D modeling

SolidPtOn, window select the 4 points that define the side face of the block in the Top viewport, then start dragging them in the required direction and type the distance you want them moved?

Hi Raymond - select the face via Ctrl-Shift click, then Move, or use Gumball to relocate the face outward.


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ExtrudeSrf + MergeAllFaces
Selecting points and moving them
Selecting a face and moving it

All three work perfectly. Lovin’ the flexibility. Than you all…great community!