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1979 Stage Mark I Restoration Quest

Started by keppi, January 09, 2023, 08:09:39 PM

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keppi

Hello EP forum -

I recently lucked into a great deal on a 1979 Mark I Stage 73 in decent shape!



The the outer case and tolex is pretty beat up, and the action looks a little like a mouth that just took a punch to the jaw  :o



But luckily the inside is looking pretty clean and sometimes downright shiny! 8)



I plan on following the restoration steps recommended here, and on the many resources this forum has connected me to (VV, Tines and Reeds, Avion, Shadetree, etc, etc.), and have already got all new "consumables" such as grommets, pedestal felts, backrail felts, hammer tips, bridle straps either here or on the way (no key bushing felt yet, none of the keys feel super loose and it seems like a whole job in and of itself).

Everything seems pretty straightforward to replace, and there are a lot of helpful guides, but one thing I am very unsure about is the regulation of the keyboard action. Specifically the squaring and spacing of the keys that is necessary before leveling and setting keydip.

This is a picture of the bass end of the keyboard, and as you can see the wood of the keybed frame bends up a little toward the end. Is this something that could potentially make it a pain to square up the keys? If I try to square up the keytops in the curved section with something like a speed square laid on the table top, won't they now be unsquare with the bent keybed? Is there a way to bend this keybed back I wonder? Ah, the mysteries of wood.


(I'm aware those front rail felts seem awful low, I pulled out the old felt strip that was serving that purpose and replaced it with circular felts, but haven't had a chance to add the correct paper spacers for aftertouch yet)

The other question is about the squaring procedure, as you can see in the previous picture the low C is getting its lean on to the right, and so I have tried to follow some videos I have seen online and used a small hammer and wooden dowel to lightly bonk the balance rail pin to the left in order to square the key top. However, when I do that I get this unwanted effect:



The low C key pedestal is now so far to the left that it is also pushing up the hammer of the low B next to it, and rubbing against it to boot. In fact all of the pedestals on the keys of the very bass end of the piano are aligned to the left edge of their hammer, from about that low C down to the lowest E. The rest of the piano key pedestals are aligned pretty close to the center of their respective hammer. Is this also a side effect of the curved keybed, or did these keys all just get smacked way out of wack some time in the past 40 years and I need to massage them back with infinite patience?

I'm glad I found this forum and hope that someone else out there can be helped out by my restoration questions like I have been by all the discussion and knowledge I've gleaned from here.

References:
Howard Piano Industries Squaring and Spacing Keys Video
https://www.youtube.com/watch?v=BaVfnJdOkl8

Max86

Hey Keppi,
How's the restauration going? Just stumbled over your post, have you solved the issue with that low C yet? I wonder if the whole key might be warped? In that case this video might help.

https://youtu.be/NYf1pea4lMU?si=0PgazhaU73gHSiUj

In the mean time thx for that Howard piano link about squaring keys, my Rhodes has some slightly off balance keys. I read that you can nudge the pins with a hammer but was always afraid to crack the wood so I left it for now. I'm now gonna try this method :)

Also, there has been a lot of discussions about shimming the front rail pins and I think mostly people agree that the front rail felts don't serve the same function as in a acoustic piano, on a very heavy strike they might prevent damaging the keys but other than that the key dip is determined by the stop lock position of the key pedestal and the hammer. In any case, the felt should only contact the keys when you press the key into after touch.

All the best!