Changing the default ACL of Google Cloud Storage can be a bit confusing sometimes.

After quite a bit of Googling (I know, I know) I found the solution.

Google is moving more and more interactions with their Cloud to the gcloud tool. But part of this is the older gsutil tool. That allows you to control cloud storage.

The default ACL is simply the permissions that will be given to objects that have not had any explicity defined. Great for just a image CDN etc.

So to set the default acl first install gsutil, see https://cloud.google.com/storage/docs/gsutil for details.

Then run:

gsutil setdefacl public-read gs://{your-bucket-name}

be sure to replace your bucket name. And that's it, default ACL set ! Enjoy.