My suggestions - forget the FSR and make the machine robust enough so that calibration, once done, persists for a while. I just built a Kossel mini and found quite a few things in the design that make calibration inaccurate.
Screwing bolts into plastic is a very bad idea. It means that you cannot tighten things up fully and they will loosen quite quickly with temperature fluctuations.
Electronics failures are often related to heat. Trying to cool down electronics under a heat bed is not an optimum situation especially given that many people will be using cheap boards with underrated FETs without heatsinks.
I suggest building an enclosure for the electronics out from under the heatbed. I consider auto levelling as a bit of a flavor of the month approach that really isn't needed if one designs the machine for stability of calibration in the first place and spends the time needed for accurate calibration.
Wood is not a stable material especially near heat. It contains a lot of moisture and will warp.
Screwing bolts into plastic is a very bad idea. It means that you cannot tighten things up fully and they will loosen quite quickly with temperature fluctuations.
Electronics failures are often related to heat. Trying to cool down electronics under a heat bed is not an optimum situation especially given that many people will be using cheap boards with underrated FETs without heatsinks.
I suggest building an enclosure for the electronics out from under the heatbed. I consider auto levelling as a bit of a flavor of the month approach that really isn't needed if one designs the machine for stability of calibration in the first place and spends the time needed for accurate calibration.
Wood is not a stable material especially near heat. It contains a lot of moisture and will warp.