Hi Avery, read this and a few other posts and I have a few thoughts below. Avery Todd wrote: > List, I've talked to the shop tech and he told me that he'd had to > raise thestack some because the hammers weren't hitting correctly. My > firstquestion is what effect would that have to how the action would > thenhave to be regulated? I almost wrote out my thoughts last night, but decided to check them with an action model this morning at work. If you just raise the stack and do nothing else, the whippen is going to drop relative to the stack to meet the capstans. This causes a change in a few angles and a few centers distances, and one of the results of all this is that the hammers drop lower relative to the Keys/ Back checks. So that you report that the hammers are resting on back checks, this shouldn't surprise really. I wanted to also ask what about the hammers hitting was wrong, and you mention over centering. Seems to me that this then you need to know whether the hammers were actually hung wrong to begin with, or if the stack actually needed raising. If raising the stack was an answer to a poorly hung set of hammers then its not really the right thing to do ... or what ? What's the rake and the bore length suppose to be on a New York D ?. What's the distance between the hammer shank center and the string height ? Isn't it such that with the shanks parallel to the strings the hammer should be just touching the strings, and if the rake is correct also at the proper point ? A few other things... Moveing the stack will also increase the differnce between the letoff button and the jack tail. The whippen drops a bit but the hammer rail follows the stack completely. With the same key dip as before, same capstan height, and same letoff button setting, the Hammer will have an increased strike distance and increased lettoff distance. If you then adjust for proper letoff, you are not going to have enough key dip / aftertouch... so a few punchings could be removed to fix this resulting in a 10mm + dip, a 2 inch blow, hammers resting on backchecks, and I think (tho I will no doubt have to think on this all evening...grin...) slightly increased leverage resulting in a bit lighter touch. If you have too much drop, that fits as well... as it would be neccessary to raise drop screws and that might result in them draggin on the bottom of the pin block, or needing to be up higher then then actually can effectively be regulated (you can check easily to see if they are at this point by just looking at them) Anyways.... just my thoughts on the matter. If anyone can shoot holes in my reasoning... please... by all means do so. Neat to try and think these kinds of things through from afar. Seems to me tho, from what you wrote... that the hammers were hung wrong, and thats what needed addressing, not the stack. > Regards,Avery P.S. At least they corrected some of the problems with > the damper lift,even though I don't really like the damping, either. -- Richard Brekne RPT, N.P.T.F. Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html
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