Hi Ed,  OK. I need some more info: How's the convergence between key and wippen, i.e. the magic line?Are the capstans buried in the keys or too high?What's the key ratio? Are the bore specs (string height minus hammer center height) in the normal range?What is the knuckle diameter?On a well-regulated note, how does the jack relate to the knuckle at full dip? What is the dip? What are the friction numbers?Sounds like you might be able to raise the stack, and you could use heavier hammers (say, SW in the low top range) depending on the venue and type of use. Alan McCoy On Sun Nov 26 21:20 , A440A@aol.com sent: <blockquote style="border-left: 2px solid rgb(245, 245, 245); margin-left: 5px; margin-right: 0px; padding-left: 5px; padding-right: 0px;">I wrote: >> a 6 mm block attached to a weighted length of 2X2 on the top of the key, and a dial caliper to measure how much the hammer rises. << and >>progressively using two 3 mm blocks, will tell me if an action has a higher ratio at the beginning of a hammerstroke (bad progression), or if the beginning ratio is lower than the final, (good progression). << Dale writes: << The use of smaller than a 6 mm block takes us in the direction of action acceleration. >> Exactly. I have found that an action in which the ratio increases as the hammer travels feels better. I call this "rising rate geometry". Whereas I haven't always been able to detect this effect by the Steinway patented "accelerated action" half round in creating this, I have found that whenever the capstan contact patch reaches the so-called 'magic line' at the point of escapement, the rising rate geometry is there. I wrote in a much earlier post, that this set-up allows the initial acceleration of the action from an at rest position to be assisted by a lower ratio and as the hammer's inertia is overcome, the action progresses into a higher ratio. The effect is the same as having a low gear on a car's transmission for moving away from a standstill, and a higher gear for greatly increased speed after the car is moving. Consider the finger to be the 'motor', and it makes sense, (at least, to me), that a rising rate geometry allows maximum power with the least amount of effort. The same phenomenon exists at the intersection of the knuckle and jack, controlled, to a large degree by the size of the knuckle. It seems that the larger the knuckle, the more rise in the rate,(but I haven't been able to reduce the other variables to ascertain how much change can be ascribed to knuckle size). As far as confusing the method of determining ratio between this and Stanwood's, I don't use David's procedures for arriving at my relationship between SW and FW. I use a visually determined curve drawn atop the charting of my FW's. Where that curve orginates is in my choice of SW, which depends on the size of the piano, the intended venue, and the subjective desires of the pianist. There are limits to how high FW can go without bringing in unavoidable and undesirable inertial results which, in some configurations, may force the SW lower than optimum. How much keydip can be used will limit the amount of ratio available, given a set hammer blow. I strongly prefer to limit key dip to .400" and I like no more than . 30" aftertouch. Case in point. (here is the puzzle part) I am currently preparing to rehammer and reshank a 10 year old D which has a very high string height and a very low ratio (4.9). At 1 7/8 blow, the shanks are almost 1/2" off the cushions. This action currently has 17 mm knuckle distance, SW in the upper middle range, FW in the average range, and ridiculously low DW of 50 gr. in the bass, 44 gr in the area of note 25, and 40-42 gr. from note 32 on up. BW on A0 is 40, tapering down to 33 at note 73. I could elect to reduce the FW, keeping all other things near the same. However, this would not address how high the hammers are off the rest cushions. It would not increase the power,either. What would you do? ( I already have a plan of action, which entails three changes, but will be interested in other's interpretation.) Regards, Ed Foote RPT <a target="_blank" href="../parse.pl?redirect=http%3A%2F%2Fwww.uk-piano.org%2Fedfoote%2Findex.html">http://www.uk-piano.org/edfoote/index.html</a> www.uk-piano.org/edfoote/well_tempered_piano.html </blockquote> <hr>Msg sent via @Mail - http://atmail.com/