Facebook Group

Groups give you threaded discussion, membership questions and a searchable archive, all free. For hobby niches like woodworking, caravanning or model railways the audience already lives there, and a group can produce more day-to-day conversation than Discord would with the same people.

The catch is ownership. Facebook decides who sees a post, can restrict or remove the group without warning, and gives you no way to export member contact details. Treat a group as a good place to meet people and an email list as the thing you actually control.