Cargo strap clamp for hexagonal builds

I recently started artisan school witch includes woodworking and thought for a project that chest would be cool. Drafting from time to time I came up with a hexagonal design and made blueprints for myself for a prototype. While getting parts ready I met a challenge I really hadn't thought: How I could possibly press this nicely together? Fellow students suggested pair of cargo straps but doing so has few problems. The lock system and links would be against the product and it would be challenging to get it tightened evenly. To solve these problems I designed a clamp for the strap to slide through and keep metal parts from digging into my product.

Edit: Added a new version of largest model that includes embossed marking.