Custom hatching pattern

I’ve been looking through the docs but can’t find the info about a way to create a custom hatching pattern. How do you approach it in Rhino? Can you create those using Rhino alone?

Rhino supports importing hatch pattern from Autocad style “PAT” files, or importing them from other Rhino 3dm files.

From the Help file article for Hatch:

Hatch patterns
  • Hatch patterns that are loaded in a model are saved with the model. Hatch patterns can also be included in template files or loaded from an AutoCAD .pat file.
  • Use Hatch properties to change an existing hatch pattern, rotation, or scale.
  • Remove unwanted hatch patterns from the file with the Purge command.

To use hatch patterns defined in another Rhino model

  • Import a model that contains the hatch pattern definitions (this can be a blank model).
  • Define hatch patterns in the template files.
  • Copy an object with the hatch pattern and paste it into your current model.
  • In Hatch Document Properties, click the Import button to load hatch patterns from a Rhino file or a .pat file.

Chiming in more as an AutoCAD expert here. Creating a custom hatch definition in an AutoCAD .pat file can be a bit daunting. But it’s achievable. The attached image shows a couple hatch patterns I made (for Revit actually, hence one for each angle; there were ways around that even but I’m risking going off on a tangent here). There’s a website called cadhatch.combut I want to express a caveat that I have never downloaded anything from that site. It looks super useful… too good to be free… there must be some catch?
My advice would be that if your hatch pattern is very simple (just lines) you can create it yourself. If it’s complex, you’ll have to dig something up on an internet search. There are a few different ways to get a hold of a ‘.PAT’ file, it doesn’t have to be straight from AutoCAD necessarily (small chance I could be wrong here). Vectorworks also uses .PAT files I believe and has many hatches not included with AutoCAD. If you knew someone with Vectorworks, you could have them export to CAD, and then import that CAD into Rhino (hopefully it works - best to import into a blank file and not a file that’s dear to you).

I’ve used a bunch of hatches from cadhatch, they’re fine. Not an incredible variety, but there are some useful ones.