I've made these air compressor filter housings to replace the  cheap original ones  with one that flows more air and makes less noise.I've found  out that the cheap ones have lots of flow obstructions and could be improved on significantly. I've adopted the Solberg air filter Silencer design into these housings,in a attempt to make them more silent.https://www.solbergmfg.com/filters-traps-silencers/inlet-filtration-silencing

The small filter housing uses a G1/4" or BSP ¼" thread  and is 56mm in diameter.
It uses a small round filter of 49mm diameter x 24mm height with a rubber lip on it .

The large filter housing uses a G1/2" or BSP ½"  thread and is 100mm in diameter. 
It uses a small round filter with a external diameter of 70mm and internal 36mm.The height is 36mm.I've printed 2 TPU gaskets (65mm OD x 45mm ID  ,0.6mm thick) to replace the paper gaskets that where originally on this filter to better seal against the lid.
The original housing had lid on it which was secured with a threaded rod that was attached into the G1/2" thread portion .This obviously obstructed a lot of air ,so i used the same screw on lid as i did with the small filter .The TPU gaskets need to be glued onto the filter and have  some silicone grease on the other side to make sure it slides against the lid and doesn't rupture the seal.


The large threads have extra clearance build into them but still requires a little sanding and some grease .The small G/ BSP threads have no added clearance build into them.I've just sanded the male threads a little bit and added grease and they fitted really good.

All parts except the seals were printed with Prusament PETG in a 0.20mm layer height with 0.10mm layer height on the thread portions. (Variable layer height in  Prusaslicer)
Support is needed on the bottom parts of the housings .The top parts can be printed without.
I've also added the .step files of the parts ,so feel free to adjust the design to your liking.