Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Cracked plate - now what?

Because of family history and sentiment, we decided to restore my wife's hand-me-down Sohmer baby grand (ca. 1906 best guess) a few years ago. Very nice looking restoration, but it wouldn't stay in tune, so we dragged our feet on selling our other piano which was the original plan. So recently we had the tuner make a more concerted effort to tune the Sohmer over a couple visits. Then one night just sitting in the other room we hear a "bong" ring out from the piano with no one even touching it. I thought a pin slipped or something, but when he came back, we could see the cast iron plate cracked at two junctions of the frame. After some research, he said it's not repairable, so we're left with what to do next.

Is it fair to say a cracked cast iron plate can't be repaired?

Are piano's like cars? Is there a market for the other good used parts that it does have?

I'd appreciate some others' opinions what we do next.

Cry. Really there isn't much you can do
to repair the plate. Maybe our friend
at Nashville has some ideas....

It is possible to repair plate cracks, either by welding or metal stitching.

Depends on how bad the tear is.

Plates can definitely be repaired. People who say they can't just don't know how.

It requires somebody to assess how bad it is. Its a very rare skill these days for welders to pull this off but there is a company in Yonkers that specializes in this and one also out on the west coast from years back. I've seen it done by a really good welder in Toronto and he put a heat sink wrap about 8-10" away from the crack, preheated the weld spot with an oxy acetylene torch to a certain temperature (tested with thermal crayons) before laying into it with a stick welder.

This video shows it being done without the above mentioned fuss and they are claiming success with what they have done so far. For some reason it looks a bit dubious to me, don't ask me why...

https://www.youtube.com/watch?v=kRsSHShYLrY

Rod Vehrnjak is an expert at repairing cracked plates

The big question is how much sentimental value does it have?

It can be fixed, but it'll cost more than you could sell it for after it's fixed.

Absolute worst case, you could grind and epoxy the old plate to make a smooth place where the crack is, and have a foundry use it as a pattern to cast a new one. Like I said, it'll cost way more than the piano will ever be worth on the market. So, the question is how much sentimental value?

This would be totally cost prohibitive, even for a valuable piano. A more realistic option might be to have David Rubenstein construct a new plate out of welded steel, but even that strikes me as a silly idea. Cracked plates can often be repaired, so let's just go with that.

No, you cannot do that. The result will be undersized.

Perhaps it's time to transfer "family history and sentiment" to a new piano.

A plate repair is always possible.

How you repair it depends on where the break is.
Cost will be the determining factor in your decision.

We just repaired two Bechsteins with the classic cracks in the strut.

One of them has been at pitch for 60 days, no problems.

Feel free to contact me. If you can take a few pictures and send them to me that would help.

In any case, repairs will be expensive, and involve redoing much of the work that has already been done.

A question that deserves an answer is ... Why did it give out. What ever inappropriate stress brought this on, should be identified and resolved.

Expensive BDB?

Depends on your perspective.

I'd try and find a donor piano.

Expensive in relation to what has already been spent on the piano. Much of it would have to be done over.

I agree. Yes it is POSSIBLE to repair
the crack .. do you really want to risk
the time and money it will cost on a
"maybe" it will hold?

Agreed although nothing mentioned from the OP about what was done to the instrument to “restore” and many of us have experience with the variety of interpretations contained in that word.

A proper plate repair is not a "maybe" kind of thing. Properly done it is a reliable and permanent repair.

This is not to say that there aren't half-baked approaches that might not be satisfactory. But repairing cast iron to function under high stress loads is a well-known and established process. Remember, there are other uses for cast iron besides piano plates.

So he can expect some kind of warranty
from whoever does the repair?

Yes I understand welding and stiching
are acceptable and reliable repairs.. even
in maritime apps.

Here's my concern.. SOMETHING caused this
plate to fail.. either the iron is bad or
the tension is too much.. i dont know..
either way.. Wouldn't a repair just
put you in the "same boat" - same iron,
same piano - why wouldn't it crack again
eventually? Why not just get a brand new
plate instead as an insurance policy?