Non Chinese PCB makers for USA Amateurs?

[amyk]

I wonder if they're just using pieces which would've otherwise gone to scrap anyway, hence why they're "free".

[ataradov]

I really doubt that. They do such a volume that there no real point in trying to fit that into other "real" panels. It will be a huge pain to manage extraction of 5 unique PCBs from a run of 100 panelized boards.

It would be really cool if they somehow managed to make it work, and I would like to know their process for that, but I doubt that they do this.

[Berni]

Nah mass production boards are likely optimized to evenly fit into their maximum production panel size. They do their own pick and place so they also penalize the boards, so they will pick dimensions that fit well.

The point is that these cheap boards have to fit within 10x10 cm (and up to 5pcs) this makes it so that they can more sensibly be packed into the 1x1 m or so panels that run trough the production line. Of course they have some sort of highly automated system doing all this, so a computer likely penalizes all this, generates all CAM files for machines on the line, assigns tracking numbers and then the boards get packed according to the number.

But it is a pretty typical business model for giving stuff out to get users hooked, then turn some of those users into paying customers. Most websites or software have some way to get limited functionality for free just to get users in. JLCPCB just does it with physical products (where it is admittedly riskier as it can get expensive very quick)