Dimensions Units

In document setup I’ve set my dimension units to 1/8" fractional. When I add dimension my viewport drawing they read as mm.
What am I missing?

You’re missing formatting your dimensions in the right place. That’s done in Dimension Style not in Document Setup. The setting in Document Setup has to do with paper space dimensions as when you are moving something on the page.

Select the dimension tool or a dimension to make the settings. If you edit an existing dimension and want to apply the changes to dimensions going forward, get the Dimension tool, type s and sample the edited dimension. Those settings will now be memorized for new dimensions.
Screenshot - 12_21_2020 , 2_06_15 PM

By the way, please complete your profile with SketchUp version.

Thanks, Dave, I never would have found that!

I have been working with Make for several years but just started my trial of Pro.

If you will bear with me I have other questions/problems.

I get a message that “my computer is running a version of macOS that is not supported by SketchUp”. But I have High Sierra 10.13.6 which is the latest version. Is this going to be a problem?

I also get a message when opening work done in Make that: "The file was created in a newer version of SketchUp. You have version 17.3.116 you need need version 21.0.338”. But this is the version I just downloaded(?)

Another message: “Version Warning, this model was last saved in version 15.3.329. If you open it in the current version you will no longer be able to open it in the previous version”. I take this to mean that if I open my older drawings in Pro, and I ever decide to drop my subscription to Pro, I will never be able to access the drawings again in Make. This would be a serious loss of years of work. Is there a way I can save the drawings to prevent that?

Thanks so much for your patience!

High Sierra is, by Apple’s standards, an old version. There have been three versions released since then. SketchUp and LayOut will probably work on High Sierra but I don’t believe the current version supports the old OS anymore.

If you are still opening SketchUp 2017 Make and trying to open files created in SU21, you would get that message. Keep in mind that installing a new version of SketchUp does not automatically replace the older version.

You can use File>Save as… in the newer version and save back to an older one. If you are going to work on old files in a newer version, you might consider saving those changes as a new file with a new name so you can keep the older versions. Then if you decide your hobby work no longer needs Pro, at least you would have the older versions.