Machine will not calibrate.

Check both of your motors and look at the black sensor wheels - are they running where they
should? Are they touching the surface? Are the rubber o-rings intact? If it is a problem with the o-ring, then you can order new o-rings at McMaster at http://www.mcmaster.com/#catalog/119/1043/=mslq1j (look at the left side for ordering). Use part number 3044K503 and select 5” outer diameter.