Hi Rogerio, Assuming everything else has been done: level keys, space hammers, travel hammers, jack position, repetition lever height, etc., etc., then you can think about after touch. After touch should be set only after the action has been completely regulated first, this is just a refinement. Key dip and hammer blow distance go hand in hand with each other. One effects the other. Start by setting both to "standard specifications", 10mm for dip and 48mm for blow distance. Check the amount of after touch which is defined as the amount of key movement after the jack has lost contact with the knuckle. 1.2 to 1.7 millimeters. Pick the best feel for that piano by lowering or raising the hammer blow +2mm to -4mm then changing the dip from -0.5mm to +1.0mm. You want to vary each a bit at a time but if you have to use the extremes to get what you want then there is something wrong with the action or it's geometry. Checking dip should be done with the punching under the key felts because the felt feels different than the cardboard when evaluating the amount of after touch. As you change the dip or hammer blow you need to recheck your drop which goes hand in hand with ddip/blow distances. When you have the action perfectly regulated then you can vary the dip plus or minus two of the thinnest papers you have to account for differences in the action parts. Don't over do this. Newton
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