This post will show you how to replace a tuning pin on your piano. If you have it done professionally, it will cost you a minimum of $1000 to have the entire piano re-pinned. Here I will show you how to do it yourself for a fraction of that price. You can typically get a full set of tuning pins for less than $100. I will have some links at the bottom of this post with more information.
When a piano gets old (more than 50 years) the tuning pins start to become loose in the pin block (a block of wood that is built into the piano). This is due to the number of times the piano has been tuned over the years. Each time the pins are adjusted, the hole becomes a bit bigger in the tuning block.
There are several methods to take care of this problem, but the best overall method is to replace the existing tuning pins with the next larger size. All other methods are just as time-consuming, and the results are not as not as good (I speak from the reading I have done on the subject, not personal experience).
One concern in doing this is that you don’t want to crack the pin block. A cracked pin block is will render the piano useless unless replaced. To replace the pin block is very expensive on a grand / baby grand piano, but on an upright it is generally considered not doable. To replace the pin block on an upright would require complete disassembly of the piano case. The piano is built around the pin block on an upright piano.
In an upright piano, there is no way to know for sure if the pin block is cracked, but generally, from what I read, if all the pins are loose and won’t hold a tune at all for more than a few hours, there is a good possibility that the block is cracked.
The first step in replacing a tuning pin is to find out the current size of your pins. The only way to do this is to remove one of the pins. The video below will show you how to do this. First take a look at the pins to see if they all generally look the same. There may be a few that have already been replaced, and it will be somewhat obvious by the color / oxidation on the pins. If none have been replaced, then you job is that much easier.
In order to ensure that the pin block is not going to be cracked by the work you are doing, you SHOULD buy the proper size drill for the pin you are installing. In my video, you will see that I have gone with a drill that is a bit smaller than it should be for the pin. I may pay the price for this later by cracking the pin block.
Here is a chart of pin sizes. The proper drill bit is going to be .009 inch smaller than the pin diameter. Yes, that is 9 thousandths of an inch. There does seem to be some different information on the internet about the exact size of the drill bit, so there is probably a little wiggle room here, but I wouldn’t go to far. YOU MUST HAVE A MICROMETER to measure these pins correctly. Borrow one, rent one, or take the removed tuning pin to a piano shop or machine shop to have them measure it for you. I just happen to have my own, but most people do not.
Size 2/0 – .282″ diameter
Size 3/0 – .286″ diameter
Size 4/0 – .291″ diameter
Size 5/0 – .296″ diameter
Once you know the diameter of the pins you need to replace, you should buy a pin that is one size bigger. If you can get pins the same length, you may not need re-drill the hole, though there are also spoon type reamers that you can buy to prepare the hole for the new pin. I’ve read that it is best to ream the hole as a minimum.
You can buy the pins at a local piano shop if you are buying just a few, or you can buy them on-line at a piano supply house like THIS if you plan to re-pin the whole piano.
Here’s my video on how I’ve done it. Please be kind, this is my first video post.
Please post a comment if you found this video helpful!