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My customer has a 45+ year old Packard studio. A problem has developed where several of the keys won't repeat....it happens more so when the sustain pedal is depressed.

I have checked for lost motion, lubricated jack pins and the buckskins appear in good shape. Is it possible the keys need some additional weight in the form of a small key lead? What about stretching the spring? Any other things come to mind?

Thanks

Don

The wippen flange is sluggish.

It could be a tight hammer flange as well. Possibly a tight key bushing, but that isn't too likely on a 45 year old piano.

Sytematically follow the resistance, starting with keybushings. Then hammer flanges, jack movement and wip flanges. Be systematic. After resistance is eliminated as a cause, check for proper blow, dip, check and letoff. Placing a lead at the back of the key is treating a symptom and NOT the cause. The action is designed to work and if it does not it is either too much resistance in the moving parts or poor regulation.

The most common cause is the easiest to fix: the butt springs are out of place. As I said elsewhere, start with the simplest possibilities first.

Weak jack springs can definitely cause this problem, and can be tricky to diagnose if you haven't come across it before. They may still be strong enough for the jack to return, but the action design may require that they be strong enough to assist the upward motion of the key. I have sometimes stretched the spring with some success, other times it's not enough.

One of the real clues will be that if you step on the quiet pedal and then depress some keys, the keys won't return all the way to their rest position.

If you've checked all the obvious stuff and your still having trouble, try replacing one jack spring and see how it works.

You might also check the flange bushings for things like, elongation of the bushing holes, crooked birds eyes, or wear, along with checking the flange pins themselves for corrosion or something as simple as a burr inside of the bushing on the pin. Many possible causes including poor regulation, tight key bushings (on any age piano depending on the weather conditions and time of year) or a damper spoon digging into the damper lever...

Actually you should start at the front of the key when looking for a problem. Even if key bushings are worn, they can be dirty and sluggish. Lube them. Polish the capstan, teflon the wippin pad Then move to the wippen flange. Take the bridle strap and the key out of the picture. Step on the pedal when testing the wippen
If you have gotten this far and haven't found the problem, it's the wippen flange or the jack flange. A sluggish hammer flange will repeat if the bridle strap slack is adjusted tight.

Many good suggestions, especially BDB’s of checking the easiest things first. Then with baffling problems a step by step approach is best.

Something that was not mentioned, and happens on older pianos, is insufficient lost motion. If there is a divot in the butt leather where the jack strikes, the jack may not be able to reset unless there is some lost motion.

Thanks for all of the input.

Taking a systematic approach was very beneficial. I removed the problem key(s) and tried to simulate the problem by manually lifting the wippen. Everything worked perfectly. That meant the problem was most likely in the key...or improper capstan adjustment. I discovered the key bushing to be slightly tight. I cleaned the balance pins / guide pins, lubricated pins and eased the bushing. Problem solved. Thanks again.

Don