Many factors play a role in the overall outcome of PCB assembly, especially when very small components are involved. Broadly speaking, tombstoning is a problem with very small 2-pin components (0201 caps and such) and we've filtered out the following challenges:
- proper paste application
- component placement
- designing for "good" thermal properties of the PCB with regard to tombstoning
- moon phase
It seems that the effect of moon phase is least understood and researched, so I'm now designing a small PCB that is cheap, not useless (if the assembly process was successful), and - most importantly - contains some 0201 components.
So in order to assemble one thing per week to compare results based on moon phase, I need to figure out what that thing would be. It should be cheap, contain a couple of 0201s - but not too much more to keep it cheap because I expect a lot of fail here - and it shouldn't be useless.
Feel free to make suggestions in the comments!
Once the design is decided on, I'll get a couple of PCBs made, order (or scrounge) components and build my dataset.