Jon, Roger and list, Further comments on a smaller roller/knuckle. We often opt for a smaller knuckle, than the typical 10.5 mm diameter, when overhauling modern actions. This is very often possible since, for some reason, it is not uncommon for the wippen heel to be somewhat deeper than ideal, ie. the mean contact point of the capstan/heel is often slightly below the line from the wippen centre to the balance pin hole. In the event of the capstan contact being positioned below the line of centres, the installation of a smaller knuckle will improve the fiction situation for both the jack/knuckle and capstan/wippen heel contacts. I am assuming here that we talking about the typical modern action with 99mm centre distance between the wippen flange and jack centres. However, we make no changes before calculating the hammer/key ratio and the influence of any proposed changes on the friction loses throughout the entire action. Regards, Ron Overs Overs Pianos, Sydney Australia ------------------------------- Email: sec@overspianos.com.au Website: www.overspianos.com.au -------------------------------
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