[skyking1]

If you are going to be reclaiming a lot of wood something like this would easily pay for itself in one blade.
https://www.amazon.com/Detector-Sen...cphy=9033433&hvtargid=pla-1215622650706&psc=1

 

[skyking1]

It would have to act as fast as a saw stop. I don't think that would be very cheap!
That little $30 thing I linked up above is pretty cheap insurance.