---------------------- multipart/alternative attachment Richard Brekne <Richard.Brekne@grieg.uib.no> wrote:Hi Bob... I took the liberty of converting them and inserting in your reply. You changed the bore by just barely under 3 mm and you got Bob Hull wrote: David, The old hammers with the bore distance of 48 mm had a blow of 44.5mm and a dip of 11.11 mm to a 10.31mm. Let off was very close, just backed down enough to not block, drop was a little much - 6.35 mm or more on some. It plays well and repeats well with this regulation. I do not want the dip to be that much with the new hammers, and I want the drop to be tiny. >>Looks to me like you could have first lowered your blow abit and regulated key dip to around 10 most places>> If you're talking about increasing the blow on the new 50.8 mm bored hammer then that is not possible since at this blow distance the shank is only .5mm off the rest cushion. >>... but that's quite the variance in dip you show... not knowing how much aftertouch variance there was makes it a bit hazy to guess at.. but I would suppose that more or less matched the variance in dip. Drop was way to much... and couple with a deep dip suggests to me that both the drop screws were regulated to low and that there wasn't a whale of a lot of aftertouch.>> You're right, the aftertouch on the old hammers and the old regulation was at .020 (.508 mm). That is with a dip of .390 (9.9 mm) The dip decreased when I regulated the glides on the center rail and the key ht. decreased. I won't be able to go much more on the dip unless I use some thinner felt front rail punchings. >> ( If let off was reasonably close to 1.5 mm at the same time then something doesn't seem right. I mean... you had standard D bore length... short blow distance, deep keydip..... at yet little aftertouch for standard let off... Perhaps its just that the drop screw was screwed down so low that real aftertouch is hard to read into this scenario. If on the other hand you had good aftertouch and very close setoff.. you could had probably just regulated closer to specs and came out just fine. Hard in anycase to understand the need to go to a near 51 mm bore distance from this perspective. Having the hammers at exactly 90 degrees to the shank, while at the same time having the shank parallel to the strings is not necessarily a big << musto >> but if you are going to first insure this, then there are a few things you need to insure first before you decide what bore length you need to make that work. David Love covered that well enough including the ref to Bob Hohfs article series. As the thread deals with overcentering... you can allow yourself a couple two three degrees of freedom with the rake of the hammer to achieve a perpedicular to string plane impact angle for the hammer itself. Unless that also means that the shank is very far from level it shouldnt be a real big problem. Just a few thoughts... I havent followed the thread real close so excuse both the intrusion and whatever I may have missed along the way Cheers RicB>> I appreciate your comments, Richard. Bob --------------------------------- --------------------------------- Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/21/2f/43/cb/attachment.htm ---------------------- multipart/alternative attachment--
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