<html> <blockquote type=cite cite> This goes to show, that you learn something new everyday on Pianotech. After 25 years in the business, I honestly had never heard of adjusting damper spring tension to adjust touch on a vertical. Thanks for the information. Willem </blockquote> Hi Willem,                   Your reply show's a lot of class,  I hope all is going well for you now. To even out damper spring tension, measure with a pair of calipers the distance from the leading edge of the hammer rail to the leading edge of the damper blocks, (felt excluded). Set action in cradle, and prop open the damper lift rod in several placesa to duplicate measurements.   ( making sure hanger bushings are in good shape) Check that all damper heads are in a straight line, so that you will have the same damper follow on each note. Set some samples in each register and measure the tension with a spring gauge,  note reading. Install action in piano and check for desired results. Remove action to cradle and regulate the rest to match. I like to see 2-3mm of follow. This is also interactive with spring tension, upon the touch. Spring tension varies all over the map from piano to piano. But it has to be even for even touch. Damper pick up is far more noticable on a vertical than on a grand. I have found many verticals with excessive spring tension, where damper follow was the origional problem, but some wise person has tried to eliminate damper bleed by adjusting the springs. Now that is an exercise in futility. Hope this make sense. Roger </html>