CR-10s Pro 18mm to 8mm diameter probe sensor adapter

thingiverse

The standard automatic bed levelling sensor that comes with the CR-10s Pro v1 is an 18mm diameter capacitative probe, which unfortunately has poor repeatability due to its sensitivity to environmental factors. Many people replace this with an equivalently sized inductive probe, such as the LJ18A3-8-Z/BX - check out this instructional video for more information: https://www.youtube.com/watch?v=VH3zrRNOGfA. While replacing the capacitative probe with an inductive one is an improvement, there are still issues with repeatability. Inductive probes suffer from temperature drift, and their repeat accuracy is typically reported as a percentage of the sensing range (Sr in the datasheets). The large flat surface at the end of the wider inductive probes tends to collect more heat from the bed. When the nozzle is hot and the entire x-carriage gets warm, which in turn heats up the probe through conduction. This is an extremely simple fix that lets you fit a more accurate 8mm probe (sensing range 2mm) to the CR-10s Pro, so that the probe is thermally separated from the nozzle. For me, this is a significant improvement over the LJ18A3-8-Z/BX. The probe I purchased is the LJ8A3-2-Z/BX, and ensure you've bought the NPN-NO variant. I used a 6mm (flat tipped) grub screw to hold the probe in place.