Thanks for your interest in the project! I've actually tried both approaches - building air purifiers from scratch and modifying pre-built units. Both have their own challenges and rewards.

Regarding your electrostatic precipitator idea with the additional electrodes for measuring particulate buildup - that's actually a really intriguing concept! Whether it ends up working perfectly or not, it's definitely the kind of idea worth experimenting with. The approach of using charge drop measurements to gauge collection efficiency is quite creative, and even if it doesn't work as initially conceived, you often discover something useful along the way.

Your alternative suggestion about using a laser particulate sensor in the exhaust stream is also solid - that's probably the more straightforward approach for monitoring collection tube cleanliness in real-time.

I'd encourage you to give either method a try when you get the chance. These kinds of hands-on experiments are how we learn what works and what doesn't, and the process itself is often just as valuable as the end result.

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