Short Tips, bending tuning pins

[Richard Moody]

Tom 
I forgot my physics, but imagine a tuning hammer arm 10 inches, and tip at
any angle at 2 inches.  Now to bend the pin the hammer will have to be
used as a lever.  The point that supplies the force for bending is at the
end of the 2 inch tip.  Now imagine a 4 inch tip.  won't the same  force
applied to the lever handle now be reduced at the end of this longer tip? 


But really the only reason to use a tip other than 2 inches is as you
mention to clear the rim of grand pianos.  Since the manufactureres won't
make a door there, and I refuse to switch hands there, (I am better with
one hand)  longer and various angled tips are sold.  . 

On the player piano since most actions are designed to be pulled forward
for tuning, you shouldn't need a smaller tip but for occasions.   

Richard Moody 

----------
> From: Tom Cole <tcole@cruzio.com>
> To: pianotech@ptg.org
> Subject: Short Tips, Long Post
> Date: Tuesday, August 04, 1998 2:07 AM
> 
> 
> Another, auxilliary point is that longer tips bend pins more than
> shorter ones and that the shortest tip possible should be used. 
> Performing a vectoral analysis will show that the length of the tip is
> only one factor in the equation and that the angle of the head must also
> be considered. If the tuning lever is high enough to clear the plate
> struts, it matters not if the tip is long and the head angle is low, or
> if the tip is short and the head angle is high. You still end up with
> the end of the lever in the same height above the plate and the tuning
> pin has no eyes to see that you are tuning with a lever of one style or
> the other. It just knows that when you push or pull at a given height, a
> certain percentage of that force registers as a pin-bending force
> because you are not exerting that force at the level of the tuning pin.
> 
> 
> IMPO, the reason that the short tip was invented was to allow the tuning
> of pins which are located in tight spots (player action or case parts in
> the way). 
> 
> (For the record, my personal preference is to use a long tip and a
> Coleman 20° head for all grand piano tunings, regular tip and 15° head
> for uprights, short tip when necessary for players. 
> 
> Tom
> 
> -- 
> Thomas A. Cole RPT
> Santa Cruz, CA