Fixing a Loose Tuning Pin with CA Glue

Fixing a Loose Tuning Pin with CA Glue

Dec 11, 2023

How to Fix Loose Tuning Pins with CA Glue

Loose tuning pins can be major problem for pianos that can cause them to be un-tunable or to not hold their tune for very long. Some pianos may only need minor repairs however, as the tuning pins are just loose enough to cause a noticeable different in the tune quality. The video above walks you through the steps of one of several ways to fix loose tuning pins: with CA glue. We offer the parts and tools needed to make piano repairs in our online store which can be found on our store here.

Video Transcript:

Welcome to another video with Howard Piano Industries. In this video, I'm going to demonstrate how to treat the problem of loose tuning pins using CA glue or also known as super glue. This super glue comes in three different viscosities, so this is the very thinnest, and it's almost like water and it soaks in as if water, as if the consistency of water, so this is the one we use for treating loose tuning pins. Tuning pins loose tuning pins usually found in older pianos. As the pen block ages and shrinks and swells with changes in humidity and the pens are twisted and turned as it's tuned over the years, the pins eventually lose their torque and get reamed out in the wooden hole, and at some point, they get too loose to adequately hold a good tune. In another video, I demonstrated how to drive the pins further into the pin block in order to make them tighter. This is a different option, but sometimes this is the preferred option, as in this case, because this piano actually, a few years ago, I noticed the tuning pens were getting loose, and I drove the pins further into the pin block, and in doing so, I drove them into the point where they can't be driven any further in. The string coil is almost touching the plate, so it's impossible to make them go any deeper. However, after say probably been about five years since I did that procedure, the pins have loosened up, and they could use another treatment, but this time pounding isn't possible, so I'm going to use the CA glue treatment. It is a fairly simple procedure, doesn't take a whole lot of work, and or a whole lot of tools, but you do want to take some precautions.

Removing the Action

One of which is to remove the action from underneath the reason for that is because this thin super glue once it's applied, it will seep into this area, and it just can seep into the smallest hole or even where you can't see any Gap, it can seep into, and so it will go through here. If you apply too much, it could possibly end up on the other side of the pin block and on your action, so just to make sure that's not happening, we want to keep an eye on the bottom side of the pen block, so we're going to remove the action. In order to do that, first have to take the case parts off. This is a Young Chang, and the way the fall board attaches on this instrument is it just sits in these two little brass brackets and can be lifted straight out. The cheek blocks are held down in this case by big Wing nuts, so you don't have to have a screwdriver, you can just unscrew them with your fingers. And then once the cheek blocks are removed, you can remove the key slip, which is not screwed in, just sitting there on dowels. It's removed. Now we can slide the action straight out, always making sure you don't press any of the keys down, so keep your fingers away from the top of the keys. You can use the key block pins to pull it out. This one's sliding out very easily. Set this out of the way.

Preparing to Apply the Glue

So one thing I like to do before I start is to tape around the perimeter of the pin block. And what this does is it gives me a visual indication of how much glue I'm putting on, and it also gives me a little bit of a margin, so if I do spill over a little bit, it'll go onto the tape and not onto the plate. So now that we have the action out, we can put a few paper towels down just in case some glue were to drop through, but I don't think that's going to happen. I'm going to be careful, I'm not going to apply too much glue. Now, to apply this glue, we have several options. You can just cut the nozzle here, make a very small opening, and use that to apply the glue, but that might be a little risky. This glue is pretty thin, so I'm going to use a different method.

Applying the Glue

What I like to do when working with these super glues is to avoid the problem altogether of the nozzle getting clogged up with the glue. I don't ever even open the nozzle or even pour glue through the nozzle. I just take the lid off and get my glue with this suction applicator. And now we can apply the glue. I'm going to start at the base, and I'm going to put just one, probably a good-sized drop, at the base of the tuning pin, between the string coil and the plate. In this case, there's not much room between the string coil and the plate, so it's going to soak in. So I'm just using a drop or two, and it soaks in. But you don't want to try to completely saturate it because it will keep soaking in, and the glue will keep finding places to go. You're not trying to necessarily fill up a hole here. One or two drops is all you want to do. Fortunately, this glue is clear. It dries clear. If you happen to get a little bit or you don't want it on the plate, you're not going to see it. It might be a little bit shiny, but so this can go very quickly.


The other thing I forgot to mention is that the super glue glue does have an odor to it, some fumes. As you get a lot of it in the air, you might notice your eyes burning a little bit. You have to keep your distance if you're able to, and then you might want to open some windows to let the fumes out. You'd want to warn your customer if you're doing this in a customer's home. You want to let them know that make sure that they're okay with these fumes and they're not somehow allergic to them. You'd want to warn your customer if you're doing this in a customer's home. You want to let them know that make sure that they're okay with these fumes and they're not somehow allergic to them. After I treat all these pins, it doesn't take long for the effect to happen, so by the time I finish all these pins, I'll be able to go back and test the torque and see how much improvement I've made. If I feel like I want it to be a little tighter, I have been able to make it a little tighter with the second application. I wouldn't recommend any more than two applications. You probably are not going to see much more improvement after two, so that's it. You just continue in this fashion all the way up. You can test. If you feel like you need another drop on each pin, go back and do that. It's that simple. I'm going to look underneath here, make sure I don't see anything coming from the underside. I'm not really applying enough for it to soak all the way through, I don't think so, but just to be safe, you want to remove the action.


So, I hope you've enjoyed this video. If you have any questions about this procedure or the products we've used in this video you can use the comment section below and I will try to get back with you. Our website is And thank you for watching.