Action Ratio and Dip and Blow and Etc.

[Farrell]

Yes, there is room in the rep lever window to move rearward up to even three millimeters. Take a look at the following photo:



You can see that the jack long axis and the knuckle core axis are pretty close to parallel with one another. As you can see, I increased the wippen heel height quite a bit to get the heel/capstan interface on the magic line at half blow - that modification has decreased friction a fair bit.

Take a look at the lead in the keys in the photo below:



That's where my concern about lead stems from. All front weights are 0.96666 of Stanwood's maximum front weights. All strike weights have been modified to follow the line between the heavy SWs and the medium SWs on the Stanwood SW curves

Are you thinking that the slight loss of efficiency at not having the jack perpendicular to the shank at rest will be more than offset by the action ratio becoming more efficient by moving the knuckle out?

I've never moved a knuckle before. I've moved capstan lines, but not knuckles. It is difficult for me to understand how moving the knuckle out would increase action efficiency and increase dip for a given blow. I see opposing effects - less efficiency on the shank lever, but increased efficiency on the wippen lever. How does that work?

Thanks.

Terry Farrell

> ----- Original Message ----- 
>> What is the knuckle radius?
>> If you can bump it out to 17 or 18mm
>> you can increase the dip and get rid of some lead.
> 
> So you are of the opinion that my dip is undesirably small? How can you be 
> so smart to know that this action had lots of lead in the keys?  ;-)
> 
> 16mm. I'll look to see if there is room in the rep lever window. Getting rid 
> of lead would be good, I think. I have reduced the lead from six in the bass 
> to 4-1/2, but that is still a fair bit of lead compared to the ideal of 
> three in the bass to none in the treble.
> 
>> Maintain about a 90 degree angle between the jack and shank at rest.
> 
> I think it's close to 90 degrees now - I'll look to see how moving the 
> knuckle out further will affect things.
> 
>> Is the wippen flange centers at a good height? Usually 2 1/2" below the 
>> HCH.
> 
> I'm trying to imagine what HCH could be - and am failing. What is HCH?
> 
>> Jon
> 
>
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