K & C Problem

[Roger Jolly]

Hi Avery, 
            Aren't they fun.  Tapering and tailing the hammers is the only
solution. I've done lots of these Samick products.

Tail the hammers to the point where the bottom of the tail is just starting
to curve, the tailing should be square with the shanks, it will solve the
back checking problems in the bass. Those 3 or 4 grooves at the bottom of
the tails is hard on the back check leather I have seen it almost worn
through with in 2 years with moderate playing. 
This treatment will allow you to square the checks to the front of the
action, far less stressful on the centre pins and bushings.
Mass removal is about one gram. 5 at the key tip.

I have developed a set of jigs to taper with the shanks on. I taper up to
1/4" of the strike point, the removal of a significant amount of felt will
enable you to loose 1.5 grams of hammer mass.

Removing the staples will only get rid of .15 grams.

The flanges usually only have about two swings, 50/50 rubbing alcohol and
water, and leave over night to dry. This helps to avoid over shrinking.

Pull all the keys out and check them, go figure, you will find some weights
behind the balance rail pins. Knock them out and plug holes.
 
The mass removal will necessitate rough regulation of the rep springs and
back checks, before proceeding.

Micro fine the knuckles.

Adjust the wip assist spring by first opening it out so they all hang
horizontal, reinstall into the loops, stroke springs to get desired down
touch weight. 

The upper section with the weights. will now be too light if mass removal
is done all the way up the scale. ( recommended ). Use a weight behind the
balance weight point to find the balance of touch weight for the desired
down weight. This will show you what weights to remove. mark them as you go.

The mass removal has a big impact on tone quality, and is well worth doing.

Check for pulley keys, they are suspect right out of the box.

Time you do a complete regulation, allow 2 days work, sorry no short cuts,
or fast fixes.

Look over the lower section of the rep spring carefully, the jack tension
varies all over the map.

The complete job can reduce the touch weight from 10 to 15 grams.

Hope this helps
Roger






At 01:41 PM 30/09/99 -0500, you wrote:
>List,
>
>    Went to look at a new Kohler & Campbell grand (5'1" size-can't remember 
>the model)
>in a church. The pianist is complaining about heaviness. I agree.
>    However in the process of looking it over, I discovered that there are 
>NO key leads
>whatsoever, until B3. Coincidentally, the wippens up to B3 have helper 
>springs. Is this
>a "correct" way to weight the keys, using the springs instead of the leads? 
>My guess
>is no but I've never seen or heard of this before. What _is_ the correct 
>way to lead keys
>when helper springs are used?
>    Beginning at B3 there are 4 leads in the keys for an octave or so, then 
>3, etc.
>tapering off, so I suspect the hammers might be a little heavy for this 
>piano and/or
>there's a geometry problem but at this point, that's just a guess. Anyone 
>know what
>hammers are used on K & C's?
>    Any info about the "leading/spring" thing would be appreciated. Thanks.
>
>Avery
> 
Roger Jolly
BaldwinYamaha Piano Centre
Saskatoon and Regina
Saskatchewan, Canada.
306-665-0213
Fax 652-0505