This is in response to John Phillips post about hammering open the
Duo-Art expression box.  I have no clue about the pedal "half" D-A
expression box, but I indeed opened up the expression box on my 1925
Weber Duo-Art grand some years back.  It was, indeed, sort of a
"religious experience", as indicated by Mr. Grant's article.

I did it exactly as prescribed, except for the scream, of course.
After I hit the wood block transferring the hammer blow, I couldn't
tell that anything had come apart.  It took a closer examination to
reveal that the halves of the box had come apart.  It came apart
on the glue joint with nary a splinter.  Clean as a whistle.  I was
absolutely dumbfounded.  And delighted.  Sorry I can't tell you
whether there are screws there or not.

Ray Fairfield
Morgan Hill, California