---------------------- multipart/alternative attachment Richard, It's not uncommon to have bass bridge glue joints fail. I've seen it at the apron and the sound board. The question here, I think, is do you have crown and down bearing? Take a thread and from the bottom of the board, stretch the thread from one end of the board to the other with the grain. Pull the thread tight at each end and the center should be a quarter inch or more from the board. If the thread is straight, that proves that the sound board bows (or crowns) up in the center. Next, take a down bearing gauge and check for positive bearing at several points on the bass and treble bridges. If there is positive bearing and the sound board has crown, you're fine. I like to use tight bond wood glue in this case. The trick is clamping. In most cases I have had the bridge pull away from the apron. I drill and countersink four holes in the bridge, glue, and send in wood screws to pull the joint together. (I leave the screws in, just make sure you countersink enough that a string doesn't lay on the screw) In the case of the apron loose from the board, you can use the same process but the screws go in from the back of the board and into the apron riser. It is possible to remove the screws after the glue dries and then drill and plug with a dowel. It may look a bit nicer but I leave the screws in. I think it's stronger and easier. The reason that down bearing did not hold the bridge down, assuming there is bearing, is that the last three strings are so close to the edge of the board. The board has crown but the bridge riser is straight. When it is glued to the board, it is forced to bend to meet the crown. If the glue joint fails, the riser will try to straighten itself, hence the gap. You also mention that the bridge is cracked. If you mean cracks at each bridge pin, that's another repair, and that repair depends on how bad the cracks are. If the bridge cap is cracked up and loose from the board, it might be a good time to replace the bridge, or at least the cap. Send more information on all the above and we'll talk more. chris >Help!!! > I took some string measurements today from the Baldwin M grand I >am going to replace the bass strings in, and YIKES, I found the bass >bridge cracked and broken at the third string. What bothers me is >that the 3 inch section was floating about 1/8 inch off the sound >board. Shouldn't the down bearing keep it down???? I have never >repaired a bridge before, so I could use any coaxing I can get. I >took the bottom three strings off so I could put the broken part >back into it's normal position in order to make the string >measurement. I imagine I should use an epoxy glue to repair this, >right, or can I use thick CA??? It's a very clean break and the >pieces can be put back together and one can hardly tell it's broken. >Please advise. Thanks. > >Richard Strang >Panama -- Christopher D. Purdy R.P.T. School of Music, Ohio University Athens, Ohio 45701 (740) 593-1656 fax (740) 593-1429 purdy@ohiou.edu ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/c5/7a/89/99/attachment.htm ---------------------- multipart/alternative attachment--
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