Building Constellation frigates on the Great Lakes

How can Constellation-class frigates be built on the Great Lakes under restrictions on military vessels there?

A suggested explanation is that they launch unarmed and receive their weapons after leaving the lakes.

Building Constellation-class frigates on the Great Lakes prompts a question about restrictions on armed vessels there. The tentative explanation is that the ships would be launched without their armament. They could then travel through the canals to the sea and receive their weapons elsewhere. The actual construction and fitting-out arrangements are not confirmed.