You can't do that exactly. Best bet would probably be something like:
Take a backup of the primary filegroup and the archive filegroups (you need primary), put that backup onto archive storage. Then drop the tables and then the flegroups. If you need then again though, it'll be a complex process of restoring the backed up filegroups as a separate database.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability