Instead of a fixed cutter, he used a trimming router mounted on a custom clamp. [Oleg] also machined three different brass nuts to go on the bolt with a fixed cutter. First left-hand and right ...

The whole thing is held together with just four bolt/washer/nut combinations. But if you don’t have access to a laser cutter, we guess you’ll have to stick to altering pre-made enclosures for now.