Action Geometry Correction

Isabelkuh@AOL.COM Isabelkuh@AOL.COM
Fri, 30 Oct 1998 18:12:34 EST


In a message dated 10/29/98 2:28:34 PM Central Standard Time,
dms2000@PIONEERPLANET.INFI.NET writes:

>  Action spread is usually around 4
>  13/32" right?  David Stanwood has mentioned in previous classes that
>  generally the spread isn't as big an issue when calculating overall
>  leverage....I guess the next question would follow (maybe Jon and others
can
>  answer):  If the spread is greater, say 4 1/2", exactly how will this
affect
>  the Strike Weight Ratio?...or would the differences exist...still
>  thinking....in whip ratio?...Trying to sort this out.  Can we make a
>  significant difference in the leveraged system as a whole by altering the
>  spread?  (There, got that out of my system).
>  
>  Thanks for reading,
>  
>  Blubbering hammer head
>  Dave Swartz, RPT
>  dms2000@majesticpiano.com
>  

Calculating -  I get:

X(inches)	Spread	Strike Weight Ratio
0.00			4.385		5.49
0.10			4.467		5.40
0.20			4.550		5.32
0.30			4.633		5.25
0.40			4.717		5.18
0.50			4.8010	5.12

Where X is the distance the wippen pin is moved back in the horizontal plane.

As you can see, it takes a really radical change in spread to make a
difference in ratio.  There is a small change in friction as well with the
change in spread,  but I don't believe it is enough to worry about.  

I think David is right -- the spread is just not a big issue.

Scott	Kuhn							


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