A solar cell stringer calibrator has been disclosed. In an example, a method includes loading a base having pressure sensors into a solar cell stringer to be positioned under a tacking head. The tacking head is lowered onto the base. The pressure sensors measure pressure applied by the tacking head. The method involves determining whether the pressure applied by the tacking head is within a predetermined range. In another example, a method involves heating a solder joint, and measuring a temperature of the solder joint with a pyrometer and a temperature sensor, the temperature sensor disposed under the solder joint. The location of the pyrometer relative to the solder joint is determined based on a difference in temperatures measured with the pyrometer and the temperature sensor. The method involves adjusting the solar cell stringer if the location of the pyrometer is determined to be outside a predetermined range.