I often use hole with a specific geometry for valve and similar.
Is there a way to add this new geometry to the hole wizard?
You may be able to save it as a favorite for use later on depending on it's geometry.
You could also try looking into "Library Features". You should be able to save it out as a library feature and insert at will.
Yes. You need to go into Toolbox to create (configure) them.
You can get there a couple of ways. One of which is ...
Tools> Options> System Options> Hole Wizard/Toolbox> Configure
As already noted, you can create Favorites or override the default values in the Hole Wizard tables but you cannot create a custom profile shape. If you do want a custom set of hole elements (like a tapped counterbored hole or a complex valve hole stack), you would need SOLIDWORKS 2017 and use the Advanced Hole command.
Advanced Hole - What's New
Advanced Hole - Help topic
I agree with John Pesaturo, creating a Library feature is the best approach, as that will give you all the freedom.
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