At 12:18 PM 1/13/2004, you wrote: >i forget. is it always a good idea to check resistance on all action >centers and re-pin, if necessary, even if all the parts are brand new? >as i've mentioned before, i'm working on a baldwin sd-10. >and another thing, this was my second hammer filing ever, and i seem to >have taken slightly too much felt off. so i have a slightly uneven >hammer line in the bass section. > >daniel carlton Daniel, I'd say that looks a lot better than the second hammer filing that I did. Did you individually file the hammers? With new hammers I generally tend to gang file the hammers (take a strip of sandpaper wide enough to sand about 4 - 6 hammers at once). My intention is not really to take off a lot of felt but just to clean off the outside layer and to remove any cupping that came from cutting apart the hammers. By the way, when you say an uneven hammer line, I assume you mean that the hammer tops would not form a straight line when the shanks form a straight line. I would correct this in the regulation - make the hammer line straight, and let the shank line be a little uneven. Probably not better technically speaking, but some people will take notice that the hammer line looks sloppy if you leave it that way. I think it's always a good idea to check every pin in the action, even on new parts. How particular you want to be about it depends on your particular standards, the particular situation, and how much you're getting paid. My experience lately with new parts is that the pinning is not very consistent and is often not what I consider acceptable for an exacting application. Your mileage may vary. If I was doing prep for a dealer, with what they generally pay, I would just check the pins in the action to make sure that they were not extremely loose or extremely tight - for example, lift up groups of hammers and let them drop to see if there are any excessively tight ones, and run my finger along the shanks at the hammer head end and see if there's any excessive free play - see if the jacks are free and return quickly, see if the whippens swing freely, etc. If I saw any particular problem I would address those individual ones. If I'm getting paid lots of money to properly rebuild someone's piano, then I take an accurate gram gage (such as a Correx gage) and check the friction on every pin. I want them to be consistent within some reasonable tolerance. As an example, I'm currently putting new action parts on a Steinway. I'm using new Renner parts (which as you probably know cost hundreds of dollars). To take just one pin as an example - the wippen flange center - I want to see 5 grams on the gage when the flange starts moving when I put the gage arm next to the screw hole. I'll accept 4 - 6 grams. What I see from measuring the new parts out of the box is from a fraction of 1 gram (will barely move the gage) up to 10 grams. If I installed the parts on the action out of the box and checked them, the wippens would all appear to move freely. However, there would be a significant variation in pin friction. Pretty disappointing after spending hundreds of dollars, but seemingly a fact of life these days. Am I being too picky? Perhaps. If you look at that pin by itself, could the pianist feel a difference between a wippen flange friction of 1/2 gram and 10 grams? Maybe, maybe not. But if you take the sum of all the variations throughout the action that are not dealt with, then yes, a good pianist can feel the difference. I go to a lot of trouble to smooth the hammer strike weights, properly align wippens to knuckles, finely regulate, etc., etc. to try and achieve an even touch from note to note. Doing my best to make sure that pin friction is consistent just seems like part of that process to me. Some sets of parts are better than others. On some sets of parts, I've had to replace 3/4 of the pins to get the consistency that I want. Regards, Phil Ford Phillip Ford Piano Service and Restoration San Francisco, CA
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