You have probably heard about a pinblock and you might have wondered what it is. The pinblock is a fundamentally important part of the instrument. In fact, without a solid pinblock, you simply can’t tune your piano!
The big problem with the pinblock is that if it’s in bad condition and needs to be replaced you have only one option; rebuild the piano. You can learn about the process of rebuilding a piano in my video:
What’s the Difference between Rebuilding and Reconditioning a Piano?
https://www.youtube.com/watch?v=j0nYdswAMDE
This is basically taking out all the strings and removing the plate of the piano – usually using an engine hoist. The rebuilding process is the only time you will be able to access the pinblock and replace it if necessary. This repair costs thousands of dollars.
Needless to say, the pinblock is a crucial part of the piano. Its job is to keep the pins in place providing the tension necessary to keep the piano in tune.
Unfortunately, this incredibly important part of the piano can’t be inspected for problems easily. If you remove the fallboard and pull the action out of the piano, you will be able to see the bottom of the pinblock and inspect it. However, the bottom is not where most of the problems are – they are hidden from view.
So how do you tell if your pinblock needs to be replaced? It requires a bit of detective work. The first thing that will point to problems with your pinblock is if your piano is unable to hold its tuning. If you tune the strings and the pins begin to slip when you apply tension to them, there is likely an issue with the pinblock. Sometimes this problem can be fixed by using a larger pin size (more about that shortly) but it could potentially make the problem worse. If the pinblock is cracked, larger pins will just enlarge the cracks!
Sometimes you have to replace the pinblock even if everything is working fine. Eventually, a piano will have to be restrung. However, you can only restring a piano so many times before you have to replace the pin block because each time you restring, you use larger pins. Eventually, you reach a limit in pin size.
When you first string a piano you use pins called 2-op (which represents thousands of an inch). When you re-string a piano you generally use larger pins for tension – so a slightly larger pin must be used. Generally, you will use a pin 2 op larger than the last ones. So if you replace 2 op pins you will most likely be using 4-op pins. Generally, you will not want to go past 6-op pins.
So, the short answer to this is that you can re-string a piano twice before having to consider replacing the pinblock.
Hope you appreciate a bit more about the importance of the pinblock. If you have any questions or comments feel free to send me emails. Thanks again!