Kienzle might not ring a bell for many clock enthusiasts, but it was a major German producer of clocks for the general public. Kienzle Uhren GmbH, was founded in 1822 by Johannes Schlenker in Schwenningen, in Black Forest region. Jakob Kienzle joined the family by marriage in 1883 and became the sole owner in 1897. … More Troubleshooting a Time-Side Mainspring Issue in a Kienzle Wall Clock