3M™ Bayonet to AOSafety® Threaded Filter Adapter

thingiverse

Human: 3M Bayonet to AOSafety Threaded Filter Adapter ============================================= This prototype design is a 3M bayonet to AOSafety threaded filter adapter, made to facilitate cross-compatibility between COTS filters and other manufacturers' respirators. It should be compatible with AOSafety threaded chemical, combination, and particle cartridges. I was surprised to find that people still had stockpiles of AOSafety 8051 bayonet filters, so I assumed there might also be threaded canisters available. Part Description: ================ 3M_BAYONET_TO_ASOSAFETY_THEAD_ADAPTER_GEN1.stl The adapter is a single piece construction for AOSafety threaded filters that do not require clocking. It is sized based on the threads provided by cwmendel in his AOSafety to 3M bayonet adapter: https://www.thingiverse.com/thing:4205509 3M_BAYONET_TO_ASOSAFETY_THEAD_ADAPTER_GEN2.stl The Gen. 2 model features chamfers added to the 3M bayonet to filter mating surfaces, reducing sharp edges that could wear on the 3M bayonet. It also has engraved markings on the exterior periphery to identify the adapter. 3M_BAYONET_TO_AOSAFETY_THREADED_ADAPTER_GEN3.stl The Gen 3 model features changes including reworked 3M bayonet to filter geometry for proper fitment/compression against OEM gasket in locked position, reduced OAL of adapter, and removed gusset supporting printing overhangs. Disclaimers/Risks: ================ 1. Use Proper Gaskets Requires a gasket or O-ring on the interior side to ensure proper seal between cartridge and bayonet. Source a gasket with a nominal diameter of 72 mm or ~2.83". 2. Perform Proper Negative Pressure Test Follow SSPs established by your institution or workplace for further guidance. Put on your respirator, adjust straps till taught against face, ensuring no obstructions around the periphery of the seal against face. Exhale deeply, cover inhalation ports, and inhale deeply. The mask should suck tightly against your face without any air leakages. 3. Use At Own Risk – Temporarily Solution Only Until Supply Chain Normalizes 3D printing materials are not resistant to many solvents, are water soluble, and degrade when exposed to chemicals, heat, and UV/sunlight. 3D printing this adapter is only a temporarily ad-hoc solution against biological contagions. Dev. Notes: ========== 0410/2020 - Initial model release. I do not have AOSafety threaded respirators or filters to check measurements, so please report back in comments for any fitment issues and I'll release revisions as required. 04/13/2020 - Revised model based on feedback from the 3D printing community. The following changes were made: (1) chamfers added to 3M bayonet to filter mating surfaces to reduce sharp edges that could result in wear on 3M bayonet, and (2) added engraved markings on exterior periphery to ID adapter. 04/29/2020 - Gen 3 model features the following changes: (1) completely reworked 3M bayonet to filter geometry to ensure proper fitment/compression against OEM gasket in locked position, (2) reduced OAL of adapter and (3) removed gusset supporting printing overhangs. Credits: ===== Thanks to cwmendel for releasing an AOSafety to 3M bayonet adapter that allowed me to pull reference AOSafety male side threads for reference. I created female threads by offsetting the height of 0.16" DIA.