We tried to make an adapter for both 3M and Honeywell P100 filters.  The 3M bayonet adapter is a simpler design that was fairly easy to print with FDM or SLA printers.  However, the threaded Honeywell part has proven far more difficult.  In PLA we basically gave up on this working.  The threading precision is critical or there can be leaks between the adapter and filter. We are attempting to print it with an SLA resin printer (photo below), but still had issues passing the fit test.