I've seen several of these designs, and used another one for years, but it broke at the obvious weak point where the chainring holder goes.

So partially to play around with Fusion360 and partially to fix the error in the previous one I've made several new versions. This is the first one I feel comfortable sharing.

I haven't actually printed this one, but it fixes some bugs in a previous version I did print but won't share.

Share and Enjoy!

Adam