Pressure bar screw variation?

[Clyde Hollinger]

Friends,

Yesterday as I was inserting the strip mute in the treble section of a
one-year old Charles Walter studio piano, my hand brushed against a
pressure bar screw which was loose.  I assumed it had broken off, so I
took it out to look at it.  I was surprised by what I found.  It
appeared to be threaded like a bolt, with the threads much closer
together than wood screw threads, and there was a notch in the end as if
it were designed to be tapping its own threads.

Now my limited understanding of piano construction is that pressure bar
screws go through holes in the plate to anchor into the wood behind it.
In this case, however, it appears that there is a threaded hole in the
plate itself for each of the pressure bar screws.

Am I understanding the construction correctly?  Are any other pianos
made this way, or are they all made this way and this is the first time
my meager powers of observation are kicking in?

On this piano I just snugged up this one screw, but the pressure bar at
that place is out of line with the rest of the bar.  In my opinion there
is still enough downbearing, but I could drop the tension on the strings
in that area and tighten the loose screw down further to bring things
into better alignment.  What think ye?

Regards,
Clyde