Three part respirator venturi valve

thingiverse

This valve body is split into three pieces for easier printing and especially for molding to increase production. Print these three pieces, sand and paint to make glossy and fit, make silicone molds and then you can make 3-4 per hour or more in clear polyurethane or other resin. Gluing the pieces together with cyanate glues. Smoothcast 325 is clear and about $50/gallon. This way they will be view-able and cleanable. Perhaps the parts can be UV/laser/resin printed for smoothness and less finishing.