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Okay, let's see if I can crowdsource this. Say I have a PCB with a few QFN parts on it and I really really want the whole thing to look as much like a DIP-40 as I can. I can probably either 3d-print the black epoxy bits, or 3d-print a mold, put the PCB in it and fill it with epoxy or something to get the case more-or-less right. What I can't figure out is how to do the pins. Standard headers don't look anything near correct. I could make the PCB with castellated edges and harvest the pins of existing DIP-chips, but that's a bit eek. I could really use some of those pins that thick film hybrids have, but I can't seem to buy those separately... any options I'm missing here? I can source stuff from the usual suspects as well as Taobao, by the way, and this is a very small scale production (well, prototype initially, not sure if I'm gonna do anything with it afterwards), so I don't need thousands.
Brian Danger Hicks

@sprite_tm Last I checked, Ax-Man surplus in St. Paul, MN had a box of 40-pin DIP leadframes. I don't see them on their website but maybe you can call or email them and ask. You may have to describe them or send a photo though.

@Brian Danger Hicks I'll keep those in mind, but they'd need some rework for a PCB to fit in them.

@Tube🌱Time Yeah, plan at this moment is to go with @maketvee s idea of etching. I ordered some etchant (don't have it anymore, it's been eight years and two moves since I etched my last PCB) and 0.5mm copper. I'll draw myself a mask like @Garrett Mace posted, then I'll use the toner transfer method to get the mask on and then see what happens if I throw it into an etching bath. Then either nickel-plating or just using a soldering iron to 'tin plate' them, then indeed a 3d-printed jig to bend them. Hope that gives a somewhat acceptable result. I'm a bit worried about under-etching, but perhaps by putting the mask on two sides and etching it from both makes it acceptable.

Probably will take a few weeks for the stuff to arrive; I'll update y'all when I get some result, positive or negative.

@sprite_tm Apparently you can also cut through ~1mm copper, brass, or steel with one of those cheaper galvo fiber laser metal engravers, though the process doesn't look very fast or clean. Good excuse for a new tool though.

@Garrett Mace Ah, I've actually seen people do that before, it seems like a very reproducible process that probably gives pretty clean results. Unfortunately I don't really have the place to put one of those things down safely, and the price of around 750 bucks minimum is also a bit too much for a potential one-off.

@sprite_tm $750? where? I'm thinking it wouldn't work below 30 watts or so, and fiber lasers run over $3000 for that.