Don Mannino wrote: > The 1/2-round changes the way the key rolls, but I believe it actually > reduces the amount of fore-aft movement of the pivot line as compared to > a normal rail. It most certainly does. You can see the difference in action models. >It is my feeling that it reduces the ratio change as > compared to a normal rail, and that may be why it was adopted in the > first place! That's my suspicion. > It seems that David Stanwood's nifty idea does force the rotational axis > to become more stationary, although it seems there are other drawbacks > to the system, such as increasing the vertical movement of the key on > the pin. This is not a desirable motion to have, although it is > probably OK as a trade-off for improving the touch in other ways. The > amount of up-down sliding must be pretty minimal, even at the most > extreme settings. Not a lot, if at all more than in flat punching systems, I'd think. Ron N
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