[CAUT] Digest, Vol 1103, Issue 85 Moving Wippen Rail

[Richard Brekne]

Hey there Keith.

Dale is a guy I have a lot of respect for, so I take your words and his 
reports and my ears are definitely open. That said,  I have measured 
friction change that I attribute to the knuckle / jack top interface 
with any significant angle change in the jack at rest.  Where we may be 
on different tracks here is just how big the window for adjustment is.  
You mention 1-2 mm of spread... I think in terms of jack angle at rest. 
Tho I did mention there was some credence given to the idea that the 
jacks angle could be just a bit on the  B + side, albeit just a tad.

My point tho, I'll hold on too.  Whippen spread, capstan position...etc 
are best set from geometric concerns.  You can get all the leverage 
issues worked out you want without any incompatibility here.  Thats my 
take on Stanwood as well.  And I have an awful lot of respect for 
David.  Sure you can place the capstan further in or out without any 
other consideration then changing the ratio and make it work.... but 
often as not thats shooting in geometric dark.  Strikes me as best to 
change the action leverage from a geometric perspective... and then 
balance it.  Simply looking away from geometric issues by reseting 
leverage and balancing at the same time ala Stanwood doesnt add up in my 
mind... especially since the former is every bit as easy to begin with.

While we are on this bit about Ratios... there's one that seems always 
forgotten in the mixing up of ratio measurments that are better to my 
mind left separate for what they respectively are.  And that is the 
ratio of speed.  Overs made a rather large point of this some years back 
especially as it relates to the jack speed.  My point is that there is a 
lot of this stuff we really dont have all that great a handle on.  True 
enough we get some rather smooth running actions each in our own, if not 
entirely dissimilar ways... but I like to stay a bit on the safe side, 
as far as my viewpoint allows for at any given time.

Cheers
RicB





    Ok Rick, the only problem I have is the friction is measurable is it
    not? It
    was measured. There was no change in a wippen move of 1 to 2 mm. The
    action
    was weighed off. Not to the DW but the BW. Dale Erwin custom
    balances his
    actions. He said there was change in the weight of the keys due to a
    change
    in leverage. He did not believe friction had anything to do with the
    change.
    I'm not arguing, I'm only reporting actual measuring. You will have to
    discuss with Dale how he weighs his action and why he thinks
    friction had
    nothing to do. Me, I'm going to take his word that he measured and
    interpreted the data properly.