This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment Paul, and list, I think I'm starting to get a grip on it. My suspicion now is that the = arc is perhaps to large and needs to be sanded down. I think this = because of the fact that the hammers do not increase in friction when = pushed through the backchecks, regardless how I alter the angle of the = head. Sometimes it seems that there is some improvement with head angle = change, but not significant, or consistent. Suggestions on tightening = this arc? (I know, I know, someone already posted a suggestion, but it = has gone away from my 'puter. One other issue that I'm still not convinced is not part of it, is the = jack to knuckle placement. There is still plenty of room in the window = to allow for more aftertouch, and thus more clearance of the jack from = the knuckle, but I already have about .055" of aftertouch (measured by = placing .055" of punchings on top of front rail felts and seeing that = escapement just barely occurs when the key is depressed). I hesitate to = think that more aftertouch would be appropriate. Oh yeah, I forgot, I = tried increasing it last night, and it didn't improve checking anyway. = It's late. I don't like it, but it seems the jack does get bumped out = of the way a little bit by the knuckly before checking, but I'm at a = loss as to how to solve this. As I said, the jacks really can't be = moved farther forward, and increasing aftertouch does not seem to help. Also, these are new wippens, repinned upon arrival at 5-7g. Hammer = shanks also repinned on arrival. Thanks again, William R. Monroe Madison, WI Assoc. ----- Original Message -----=20 From: Paul McCloud=20 To: Pianotech=20 Sent: Wednesday, November 10, 2004 9:15 AM Subject: Re: About Checking Hi, William: If your hammers don't find increased friction when you push them = down into check, your angles may not be correct. If you take a wedge = shaped block and force it into a crack, you'd expect it to get tight, = right? The tail is arc-ed in a radius which is less than the radius = of the hammer shank length, so that when the tail meets the backcheck, = it acts as a wedge. It's possible that the radius arc of your tails is = too long (you may need to sand a tighter curve into them). The backcheck is bent so that the tail will be caught in it. The = movement of the keystick is also in an arc which intersects the arc of = the hammershank. The movement of the hammer and keystick and their arcs = causes them to meet and interfere with each other (a good thing!). = Where these two arcs intersect should be around the middle of the = backcheck head. The bottom of the backcheck should be closer to the = hammer, and the top should be farther away (this is your backcheck = angle) This angle insures that the tail finds more friction as it goes = down into it. It sounds like your backcheck angle is insufficient to = cause this to happen. See if you can angle the backcheck back a little, = and regulate the backcheck height again, while making sure it's not = rubbing on the tail on the way up. =20 It's too bad we can't see the action up close. Sounds like a good = subject for a Guild meeting/demo. Hope this helps, Paul McCloud inSaneDiego ----- Original Message -----=20 From: William R. Monroe=20 To: Pianotech Sent: 11/10/2004 6:15:31 AM=20 Subject: Re: About Checking Joe Garrett,=20 I have already bedded the keyframe, and double checked to make sure. Tom, Already repaired the balance rail holes (Onesti system - great = tool!). Joe Goss, and Paul, Rep Springs really don't seem too strong, they have definite rise, = but do not "jump-up" from check. I will try weakening them more, = though, and see what that brings.] Terry F, Double checked jack position, by bringing it out to the point of = cheating, then just in enough to function, and no change (Drat!). Paul, Great ideas. Checks are aligned, spaced, etc. I resurfaced them = prior to regulation. Checking occurs about 1/3 of the way into the = backcheck, and backcheck height is just about even or a little below the = backcheck tail at drop, checks do not rub on tails on the rise. The one = thing that is giving me concern is that when the hammer is in check and = I push them further into check, it does not happen. I can push the = hammer pretty much through the range of the backcheck without much = increase in friction. As as mentioned earlier, maybe the hammers being = hung at a different angle are to blame (if indeed that was done). I = will be checking that, but any other thoughts on why the hammers won't = go deeper into check? Thanks everyone for your input!!! William R. Monroe Madison, WI Assoc. ----- Original Message -----=20 From: Joe Garrett=20 To: pianotech=20 Sent: Tuesday, November 09, 2004 11:35 PM Subject: Re: About Checking William asked: "Also tried varying the backcheck height, which = showed no noticeable improvement with either higher or lower backchecks. Also tried = changing the backcheck angle - again no improvement one way or the other, = hammers simply will not check on soft blows." Lost in Wisconsin: William R. Monroe Madison, WI William, If you've tried all of that, then it has to be something you = didn't try.<G> Have you checked to see if the keyframe is bedded = properly? I've known that to mess up checking. Best Regards, Joe Garrett, R.P.T. Captain, Tool Police Squares R I ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/d0/d1/71/fa/attachment.htm ---------------------- multipart/alternative attachment--
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