I had to replace about 25 rubber grommets on an Acrosonic the other day; somehow they had become brittle and just crumbled up, messing up the letoff. Unscrewing all those plastic finger nuts was a lot of work. Does anyone make a nut driver for that job?

Greg Livingston
pianotuner440@hotmail.com

Welcome Aboard!

See Schaff Catalog page 42, item 60 "Kimball Lost Motion Regulator":

http://www.schaffpiano.com/catalog/technicians_tools.pdf

I remove them with a nut driver in a small stick driver/power drill, and reinstall them with a handheld nut driver. I carry 3 of these, and I can't recall which size fits which piano. They are an SAE size. Just be careful not to drop them when they come off the lifter wire.

I would have replaced the entire set, rather than 25 or so. They are all old and going to crumble, and once you are in the rhythm of changing them it does not take all that long.

What Dan said about replacing them all. I just did a set a couple of weeks ago. I use the #60 tool in a power drill. Prior to removing them, I apply 1 drop of Protek to the top of the lifter wire to help loosen the metal or fiber nut that remains after the plastic crumbles. This let's it spin off much easier. Usually the plastic crumbles away and then I have to push the tool farther down to grab the nut. When it comes off, I use a wire handle from a rubber wedge to dig it out of the tool, then hit the next one. Goes fairly quick.

When installing the new ones, I use a tiny bit of Prolube on the lifter wires and the metal hooks that hold the grommets to the keys so they'll spin on easier. They spin down nice and fast with the variable speed drill, and then it's a simple matter of regulating them.

The Baldwin drop actions are interesting, and give you an alternate to spinning those nuts up and down. It may not always be the easiest way, but I will offer another variable to you all.

Don't spin the nuts off. Pop the bottom board out and sit on the floor. Use a pair of long tweezers to slide along the whippen, from back to front, and simply remove the lifter wire from the whippen. They are mounted into a piece of bushing cloth, and slipped into a notch at the front of the whippen. I plant a thumb on the front of the whippen, and use the tweezers to yank the wire and bushing cloth out.

The rubber grommets either slide off, or crumble to the touch, and the new grommets are slid into place. The circle of bushing cloth goes on, and the lifter wire is slid back into the whippen. Bonus; very little regulation of the nuts is required...like none at all in many cases. Never more than a turn or two at the most.

Figured this one out one day when I did not have the drill handy, and did not want to spin those nuts with a pair of pliers...endlessly spinning my wrists and fingers trying to turn 88 nuts hundreds (...thousands?) of times to get them on and off.

The trick is supporting the whippen with your thumb when easing the wire out of the whippen. The cool thing is the minimal regulation when done this way. Time saving? Not really...but if that drill is not with you, or you don't have the replacement nuts handy, then doing it this way is something you might want in your repetoire.

A former Baldwin store tech,
Where I started this ride!
I am,

By the way Jeff, it's "normal" for the rubber grommets to get hard and brittle. You may also run into old plastic elbows on spinets that get brittle and begin breaking. Schaff has replacement elbows that snap into place. We'll assume the modern plastic is better that the old I consider it all a little bit of job security!

Jeff, are you talking about the round donut grommets? The procedure I laid out was for the square ones.

When did Baldwin start using rubber grommets in the Acrosonics? I've got an Acrosonic from 1950 that doesn't use this design and I can remove the action quite quickly. How is it to remove the action with the rubber grommet design?

Dear Loren,

This is specific to the Baldwin spinets with the plastic nuts, red-felt washer, and round rubber grommets below them. With the square grommets, where the nut is integral to the grommet, you do indeed have to spin those puppies off. Another tool for that job, for the square grommets, is the capstan adjuster for wooden capstans; the 4 sides of the tool will fit snugly and evenly on the square, and that also can be fitted to a drill.

What the thread, and my answer, referred to was the problem of spinning those gray plastic Baldwin nuts a million times simply to get to the round-donut grommet below. And...with the Baldwin spinet...that may not be needful. If the nut isn't moved, and you pull them off as described, you only have minor regulation to deal with once they are replaced.

And yes...it feels a lot like an elbow replacement job. I knew someone would get that impression! But, what we're talking about is the grommet that fits into the back of the key. These either harden and break, or start ripping out of the keeper, and must be replaced. AND...do them all! Or you'll be dealing with it piecemeal for years.

Just sayin',
There's always another way,
Practically speaking,

I like Jeff's answer, removing the sticker from the Whippen! I haven't spun a nut in years. I've been cutting the old rubber off with diagonal cutters, then cutting one side of the new rubber donut and slipping them on the sticker. I make sure the slit is facing towards me when I slip the replaced donut on the fork, and the fork holds it tight. If the slit in the donut faces away from you, the sticker may slip out though the slot.

If you happen to try to adjust the square type of nuts and the rubber simply crumbles away you can be in big trouble if you don't have replacement nuts! This happened to me ONCE. Fortunately I had some rubber, T-shaped, bushings for the end of damper rods. After removing the nut, these can be fitted over the rod and into the fork, with the cross part of the "T" on top of the fork, to keep the rod in place. Then the nut is replaced and adjusted.

Any port in a storm.

I like to demonstrate a crumbly nut to the customer. Nothing like a graphic display to sell a job, however, I hate replacing Kimball style nuts, especially since the replacements from the supply house are very squishey and hard to work with.

What happens when you need to remove the action and disconnect the lifter wires? Will the grommets stay in place?

A tech a few counties over replaces crumbling square grommets with round ones:

1. Crumble the old one, leaving only the metal nut that remains.
2. Slit a round donut grommet and pop it on to the lifter wire and fork, underneath the nut.
3. Adjust.

Thoughts? Seems like an efficient way to do it, though definitely different. I still worry about the slit grommets when the time comes to remove the action.

Well, as part of grommet replacement, I always pull the action and tighten screws and align hammers, and fix anything else such as corfam butts. I do that with elbow replacement too. You and I both know, Loren, this is probably the only time a spinet action will be pulled.

I've done that twice now, with good results.

As long as the jack springs don't ever need replaced. Or jack flanges don't come unglued. Or......

The quality of the new square grommets leaves much to be desired. At the slightest resistance, the rubber outer part starts spinning independent of the inner nut when putting them on. A drop of Protek on the lifter wire does help this a lot, I find.

Nothing sells the job better than the customer hearing that awful crunch when the old grommet disintegrates.

The Schaff multi tip screwdriver fits the grey nuts perfectly when there is no tip in the screwdriver. You can ratchet them by hand if you dont have a drill handy.