>>Instead of trying to give you a bunch of standard things to do I'm just going to mention that if let-off is around 2 - 3 mm, key dip around 10 mm, then you will get appropriate jack release/clearance by regulating blow distance in or out . Daniel, Good advice from Ric, but don't forget to adjust the lost motion change when changing blow distance or you won't see any change in jack release/clearance. Ric, I don't think I've ever remembered hearing that jack escapement on a vertical is not aftertouch. I'm curious as to why? Seems like in both cases we are talking about jack movement after clearing the knuckle. Dean Dean May cell 812.239.3359 PianoRebuilders.com 812.235.5272 Terre Haute IN 47802 -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Richard Brekne Sent: Tuesday, June 17, 2008 5:03 AM To: pianotech at ptg.org Subject: set letoff to get acceptable aftertouch? Hi Daniel. I'd put big question marks at the end of this post as well. Instead of trying to give you a bunch of standard things to do I'm just going to mention that if let-off is around 2 - 3 mm, key dip around 10 mm, then you will get appropriate jack release/clearance by regulating blow distance in or out . You can see this very clearly in an upright. Just press the key and look at the jack top. If on a 10 mm dip with 2-3 mm let-off the jack comes clear of the knuckle but not more then just clear... then whatever bobbling you have is the result of something else. This something else could be a host of things and seems to me to be what folks should be listing up for you... i.e. causes of bobbling. I'll give you a few and let others fill in if they want. Bad back check felt, too strong return springs, too strong damper strings, too close jack stop rail, too much friction on the knuckle/jacktop interface... and just plain bad action design geometry. As far as your heavy keys.... Points in the direction of some rather obvious to find fault. What have you done to diagnose that situation ? You describe something in the nature of 50 pounds to actuate these keys, which perhaps is not quite as heavy as they really are... but still something is clearly jamming/interfering these. They are all together yes ? Not just one hear and one there ? Look for something in the action or crammed in behind it. Just did a rare cruise boat job the other day. Two Steinway B's rather new. Boat had just left South Hampton and arrived in Bergen on Saturday. Jammed key on the instrument they used for classical concerts and it happened 5 minutes into the first concert. Hammer was nearly at drop position and key wouldnt return. There was half a broken high treble string laying in the V of the plate between the treble and bass sections... I think you see where this is going.... :) Highly professional work by the fellow who changed that string. Fixed of course in 30 seconds... producer watching and aghast at the fact that 4 days of concerts had had to be canceled because of this. Dig carefully around in your action... you'll find whats hanging up those lower notes. Cheers RicB hi all would any of you ever set letoff far away enough from the strings to get acceptable aftertouch, if nothing else seems to be working? it's a crappy piano, a bradbury console. i'm need to get an acceptable regulation, but nothing more. i've tried playing with strike distance and dip and can't seem to get good enough aftertough in a small section of the bass (perhaps two and a half octaves) to avoid bobbling. also the dip is about 12 mm. is it a sin to go deeper to get acceptable aftertouch? i don't remember hearing anyone mentioning keydip that deep. oh, and another thing. some of the sharps and naturals in lower half of the bass section feel heavy. the only thing i can compare it to in my imagination is having a 3 inch sharp key, with the balance pin being 1 inch away from the player end of the key, and having a 10 pound weight sitting on the other end of the key. now can you imagine how that would feel? and it seems like the higher i have tried setting the key height to get a little more dip, the heavier it feels. ?!?! daniel carlton
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