Pinblock/Frame Separation

[JIMRPT@AOL.COM]

Well lets look at this from a fifth perspective......., i.e., the plate and 
block were at one time attached firmly to the backframe and it did not crack 
in that position......it has migrated to the present position of block/back 
seperation and the plate has not cracked (can we agree on this much?)  Given 
this set of parameters, pulling the plate/block back into position 'should 
not' cause the plate to crack. After all, the plate is just going back to a 
position it has already been fastened in and returning it will impose no 
extraordinary stresses to which it has not already been subjected.
(keeping in mind that the piano is said to be overly flat already)

 Now without regard to whether the downbearing is affected by this plate 
shift, either way, the plate and block need to go back as close as possible 
to the factories positioning, unless you desire to go into rescaling and 
redesigning. I don't think I would bother doing that with a model 243.

 Doing this repair is simple from my viewpoint.
1. Clean out the crack as well as is humanly possible. (use your favorite 
method)
2. Using your favorite type clamps pull the back/block&plate back together so 
that the crack is as reduced in size as possible. 
(using too many clamps is a virtue here so as to spread the pressure on the 
plate widely..... pressure should be applied to each suceeding clamp a little 
at the time rather than trying to snug one little section up as tightly as 
possible before going on to the next one. Alternating tightening works well 
for me.)
3. Take out the screws holding, or not holding as the case may be:-), 
everything together at the top of the plate, typically there will be 5 or 6.
4. Using your favorite size drill thingee drill a hole completey through the 
block and back assembly from the FRONT side.
5. Insert the proper sized 'carriage bolt'/washer combination from the back 
side and install a washer and nut loosely, that means don't snug it up yet, 
from the front.
6. After all bolts/washers have been installed loosen each nut so that it is a
prox three (3) full turns (depends on tpi) away from the plate.
7. Loosen each clamp a little until most of the pressure is off the clamps, 
the crack has reopened and the nuts are helping hold the plate/block.
8. Pour/squeegee/spatula your favorite adhesive down into the crack.
9. Reapply pressure to the clamps and draw the crack back together a little 
at the time. (patience counts here and it won't take any longer)
10. When the clamps are as tight as you feel needful, tighten down all the 
nuts.
11. Allow your adhesive of choice time to set up and remove clamps.
12. Tune the thing and collect your well earned fee.

Using the Nossaman method I left out all of the common sense stuff like don't 
drill a hole in your hand or finger, don't clamp your pinkie too tight, don't 
glue action parts together, don't make a mess and clean up the mess you make, 
etc.... :-)
Have fun, Terry.
©Jim Bryant (FL)