Modular bolt together frames

[Ratliff]

A little known fact is Sammy Miller's "Oxygen" rocket dragster used a two piece frame which bolted together behind the cockpit. This was an adaptation to the shop where it was built being too short for the full length frame.

[MCR]

Dunno.  They used bolts and rivets to hold the SR-71 together, and it was fairly reliable and pretty fast.

Welds are only safer than fasteners if you don't use the right fasteners.