My first ‘real’ panel.
It’s somewhat small, but it’s the real thing this time. I have made one panel before, but it was just 4 identical boards thrown together. It did have mouse-bites and routed board edges, but no frame, no alignment holes and no fiducials. Not that I really need fiducials… Where’s my P&P machine? This basically was an exercise, just to be able to say: “Yes, I’ve done that before.”
The boards were ordered at hackvana.
This time I also ordered a stencil for this panel, not just a tiny one for a single board.
The paste layer used for the stencil:
Rendering shown on the OSH-Stencils website during the checkout process.
As of now, you don’t have to upload a gerber file for the ‘etching’ layer (info text…) anymore. You can now enter up to three lines of text using their web interface. Makes marking stencils with a unique identifier a lot easier and faster.
In this example I used the project name and the git commit-hash for that purpose.
You see the scheme… have unique identifiers on the stencil and the circuit boards. As the project also contains the schematic, there’s almost no chance to order the wrong parts as well.
Of course this ‘idea’ is neither new nor revolutionary – it should be done like that all the time – but git makes it obscenely easy.
Below you’ll see the first real-world test with the stencil + panel. Apparently I need some more practice and / or the DFN10 footprint and / or the squeegee need improvements.
Result: 100% working boards, but only AFTER reworking 100% of the DFN10 chips. Some had shorts, some lacked solder. All other parts reflowed just fine!
I should mention that the squeegee I used was suboptimal. It resembled a tool that is usually used in the kitchen, presumably for parting batter / dough. Its edge wasn’t as uniform and smooth as I would have wished. I’m also not sure if I managed to hold it at the optimal angle.