Hi Rolland: When you say the jack tender is blocking hard, I assume you mean that the jack has hit hard against the jack stop felt in the slot of the repetition lever (balancier). If this is the case, there is way too much touch for the amount of hammer blow regardless of the geometry. If for some reason you were compelled to stick with the 1 5/8 hammer blow, then you must decrease the touch depth until the jack just barely excapes from the knuckle. Any additional amount of movement is just too much after touch. This is the greatest cause of broken jack tenders, not hard playing. This next is for those who consider themselves beginners, not you Roland. Many piano companies have published action regulation specs to be of assistance to young technicians in the field. Unfortunately, some of these specs do not work. They don't bother to tell you when they changed action spread specs or sometimes some other things, so when you are trying to regulate an action to exact specs from a manual, you may or may not be making the action work its very best. So, what is the best thing to do? Work with an action model and find out what varying each of the measurements actually does and how it affects other adjustments. A thorough study of aftertouch is one of the most valuable exercises. The Yamaha class on aftertouch is superb. It helps you to understand the effect of changing hammer blow, let off, keydip, and the resultant aftertouch. Whenever I am training someone in grand action regulation, I alway regulate until everything works right, then while they are not looking, I change one thing only, and ask them to identify the one thing which was changed. Quite often, changing one thing will affect two or three other things. For example, if I changed the dip to .020 deeper, the backchecks would catch higher, there would be too much aftertouch, the dampers might crowd the upstop rail, etc. The students job would be to decide which was the one thing which I changed. The real student of action regulation will want to set up tests like this for himself to see that he really understands grand regulation thoroughly. After varying each of the adjustments one-at-a-time, you will have a better understanding of trouble shooting regulation problems. Then, try varying two things at a time. It can get really tricky here, because some regulations changes can offset others. An example is: lowering the key height after the touch has been made deeper. This still has other effects besides those two which cancel each other. In the Baldwin manual, it used to suggest that you regulate sample keys and hammers in each section, before making 88 mistakes which take longer to correct. GOOD ADVICE. Jim Coleman, Sr. On 26 Aug 1997, Rolland Miller wrote: > Hello list, > > I am servicing a Steinway B grand made in about 1968. > > While checking it out and tuning, it didn't feel right. I found: > 1. Jack tenders blocking hard. One broke while I was tuning. > 2. Blow about 1 and 5/8" which is short of the 1 3/4" that Sienway suggests. > 3. Key dip was not real even but in the .390 range. > 4. The drop screws were screwed way down but the drop wasn't as wide as I > expected from looking at the position of the drop screw tops. > 5. Action frame and flange screws where tight. > > The specs are off but not so much that I would expect the tenders to block as > "hard" as they were. > I lowered one capstan to get that hammer to a 1 3/4" blow and the jack still > blocked hard. > > When I go back this Friday I plan to take the stack and keys off the key frame, > set the glides, put it back together and see what the regulation specs are then. > Then diagnose to see what the problems are at that point. > > This is the first "M" I have worked on and I would like whatever suggestions > list members can give. Especially if the "M" regulates a little different from > most other pianos. > > Thanks ahead!!!! > Rolland Miller, 70642,3604@compuserve.com > >
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