This is a short tutorial to show how to replace a click spring in a Hermle 1151-50 movement. The principle will apply to other Hermle main wheels as well. First, have on hand Timesavers #11617 or #19282 (click springs) and #20106 (lock washer). I had the 11617 in stock, and just cut it a little shorter with a #4 Jewelers saw blade. No temper loss that way. To remove the old lock washer, just pry up the tabs with a small screwdriver, and remove it. Take the wheel apart, and set the parts aside. Remove the old click spring (or what's left of it) by inserting a small punch into the holes on the opposite side and tapping it out. Insert the new click spring, being careful to get it on the right side of the click. On this movement, the click pushes up on the tail of the click. Just hold it and tap it into place. Check it for proper tension on the click, and bend it a little if needed. Reassemble the wheel, and place the new lock washer in place. Use a hollow punch to seat it firmly (but not too tight) against the spider spring. You're done! Easy job, and no need to hesitate to do it yourself!