- cross-posted to:
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- cross-posted to:
- [email protected]
This was the first time I’ve used a stencil and solder paste to build up a pcb. It was so much easier to get all the components aligned and soldered on the board (on the back, there are 38 0603 capacitors which are always time consuming to hand solder). After just had to clear a few bridges and added a little extra solder to U1.
If you happen to have photoresist and some spare etchant on hand. You can make your own stencils with a soda can. Use something like 600 grit on the outside surface, clean it shinny, don’t touch the inside at all, in fact protect it with some additional packing tape while sanding the outside. Then make your pads ~30% smaller than normal to compensate for how thicker aluminum will etch into the sides and slightly circularize each hole. Then etch with anything that will work with copper. Hydrochloric acid is nice because it is clear and easy to see through. The plastic liner on the inside of the can will flake off easily once the etch goes all the way through. Soda cans are the perfect thickness, and this makes it easy to do repairs or one off prototypes, especially when you are not doing a solder mask on a tighter footprint with traces under the chip near the pads.
I’ll have to keep this in mind if I ever go down the home PCB fabrication root.