Hey everyone, I just wanted to share a hardware modification that I made and have been using successfully for the last few months. We were in need of better aeration of the cultures which led to us switching to 15x8 mm cross stir bars, which also lead to quite noisy OD readings due to scattering of the light on the stir bar. To increase the height of the plane where the OD is read I designed a spacer ring that can be screwed on between the “baseplate” and the mantle to give around 5 mm of additional clearance. The stl file can be found attached to the post (just remove the txt file extension) as well as a picture of the assembled set-up. Hope this can help some of you 
Best, Kai
Spacer_Ring_V2 1.stl.txt (1.3 MB)