I built a few custom scientific measurement equipment over the years during my Postdoc and at a biotech startup.
System to monitor crystallization/freezing of ice in 2-5nm diameter pores within silica (coated on molybdenum mirror) by infrared absorption (https://lylegordon.ca/researchoverview.jpg).
Micro-rheometer to measure viscosity of samples as small of 3uL of liquid (this was an improvement on a NIST design that didn't require calibration of capillary diameter)
Porosimeter to measure active (flow through) pore size (5-50nm) in tiny membranes that only flow a few microliters per minute of helium (gas).
Custom time-resolved pycnometer to measure flow rates of membranes attached to a closed volume, detect leaks, and measure the internal volume.
System to monitor crystallization/freezing of ice in 2-5nm diameter pores within silica (coated on molybdenum mirror) by infrared absorption (https://lylegordon.ca/researchoverview.jpg).
Micro-rheometer to measure viscosity of samples as small of 3uL of liquid (this was an improvement on a NIST design that didn't require calibration of capillary diameter)
Porosimeter to measure active (flow through) pore size (5-50nm) in tiny membranes that only flow a few microliters per minute of helium (gas).
Custom time-resolved pycnometer to measure flow rates of membranes attached to a closed volume, detect leaks, and measure the internal volume.