Checks cause hammer bounce ?

[Overs Pianos]

Ric,

I've found that the symptom you describe is most often a bedding 
screw (glide bolt) adjustment problem. I'm probably mentioning 
something you already know, but since Steinway keyframes are made so 
that the front rail of the key frame springs up slightly at the ends, 
you need to clamp the ends down to the keybed before adjusting the 
glide bolts.

The dial gauge method is unquestionably the last word for setting the 
bedding screws. The traditional paper shim adjustment method is 
highly error prone, even in the hands of an expert. Once, at a 
Steinway seminar at the Sydney Con in 1992, the visiting S&S tech 
showed us on the first day how to adjust the bedding screws using the 
paper method. The next morning I brought in my dial gauge and wooden 
mounting block, which showed that the adjustments of the previous day 
were all over the shop. Its quicker and totally accurate. The 
procedure was posted in the Journal a couple of years ago.

When David Kinney and I were at Samick doing some work in January, 
the head technician showed us his dial gauge and block for setting 
the bolts in the same way. So that's two techs I know of who came up 
with the same idea independently. The third was Richard Davenport.

Anyhow Ric, if you didn't use a dial gauge for setting the bedding 
bolts, its time.

Regards,
Ron O.

>I ran into a symptom I haven't identified before.  I was bedding an 
>older Steinway D today, and made sure all three rails were good and 
>done in the right order... yet I was still getting too much hammer 
>bounce in the bass section on a hard blow.  The rest of the piano 
>was just fine... just the bass section had this problem.  Started 
>troubleshooting by first lifting the whippen up with my finger and 
>hitting the key hard to see if there was any bounce... nope..  Then 
>I lifted the hammer with a shank hook and hit the key hard... still 
>no bounce.... Then I noticed that when I lowered the shank enough 
>for the back check to make contact with the hammer tail... the 
>neighboring hammers started to bounce.  When I let the hammer go 
>into full check the full effect of neighboring bounce kicked in.
>
>I haven't managed to pounce out what the cure for this is.  Checking 
>distance is 15 mm... action is reasonably well regulated... drop is 
>a bit deep but letoff, dip and aftertouch amounts are all well 
>within good tolerances.
>
>Any advice on the matter is of course very welcome.
>
>Cheers
>RicB


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OVERS PIANOS - SYDNEY
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