This is not a great model, but at this time it is the only trigger lock out there.  I used claude.ai to come up with the model and fiddled with it a lot.  It uses the BOSL2 library for threads.  The goal was to be able to dump cleaner in to my airbrush paint holder and run it through the airbrush without me standing there holding the trigger.  This one fits the Paasche VL.  I suspect that it can be adapted to fit a number of airbrushes by changing the ring size that fits over the airbrush.  It should be within approximately 0.33 mm of the airbrush diameter.  Too much play in the ring and it won't hold the trigger in a position where it sprays, and thus cleans.