Author Topic: How to get more key dip? (Rhodes)  (Read 232 times)

Offline jwc44

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How to get more key dip? (Rhodes)
« on: September 08, 2020, 12:32:43 PM »
Hello

I have a 1977 Stage 73 and have it completely torn down and cleaned.  I decided to replace everything, I have rebushed both rails, , new combs, new tips, damper felts, bridle straps, ect...  I am in the process of leveling the keys and then am going to do the bump mod.  I have limited keydip at both the bass and treble ends with 3/8 being the shallowest on the bass end with just the felt and no punchings.  This rhodes has the aluminum action rail.  Is there a protocol to get more key dip?  Also in a mock up I am finding that the name rail is too low pressing down the end keys and making it worse.  I figure I can just shim the name rail on the cheek blocks.  Any thoughts?  Thank you in advance.
« Last Edit: September 08, 2020, 12:39:35 PM by jwc44 »

Offline sean

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Re: How to get more key dip? (Rhodes)
« Reply #1 on: September 08, 2020, 08:52:39 PM »

Here are my thoughts.  Hopefully they will inspire one of the repair shops to chime in.
The service manual has a section on key dip, and it doesn't say how to change the key dip!
http://www.fenderrhodes.com/org/manual/ch4.html#4-1

It is my understanding that most folks hope that the key dip can be adjusted by paper punchings on the balance rail.  I don't know how much this works.  It doesn't.

I might suspect that the keybed is not dead flat.  Is the keybed solidly screwed down?  Are there any gaps underneath the keybed - between the keybed and the case?

Also, you just replaced all the hammer flanges - are they mounted perfectly evenly?  Maybe one strip of hammer comb is drooping near the ends of the keyboard.

What is the chance that your piano has been in use for decades, and that over that time, the felt under the back end of the keysticks has become heavily worn in the areas most played... so the felt is thinner in the middle of the piano, but still relatively fresh and thick near the ends of the keyboard.   Hmmm... that's my bet.

You should have enough felt and paper punchings on the balance rail to keep the keys from bottoming out on the front rail felt strips or felts around the guide rail pins.

Then the key travel is limited by the key pedestal travel between the rest position and the stop-lock position.
Then the key travel is limited by the key pedestal travel between the rest position and the stop-lock position.
................................................................................between the rest position and the stop-lock position.

To change the travel between the rest position and the stop-lock position, you can:
1.  Make the key pedestals shorter, or simply shave off a bit of wood from the bottom back end of the key.  Thinner pedestal felts give only a tiny bit of extra travel.
2.  Replace the felt underneath the back end of the keys with thinner felt.  Again, this will only give you the difference in felt thickness, so not a huge change in travel.
3.  Raise the hammer cam stop-lock position by raising the whole action rail.  Shims under the action rail are not illegal.  This could give you a huge change in key dip.  You should probably expect to have to raise the position of the tines, probably best by putting shims on top of the harp supports.  And you will want to check the strike line.

Sean
« Last Edit: September 08, 2020, 08:57:24 PM by sean »

Offline jwc44

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Re: How to get more key dip? (Rhodes)
« Reply #2 on: September 08, 2020, 09:22:09 PM »
Much appreciated Sean.  I took this Rhodes to ground zero, replaced the back felt, bushings, squared the keys, and leveled the keys with the keybed screwed in.  The key dip is right where I would want it without the felts on key pedestals so im 99.44/100% sure the follwing is TRUE

"Then the key travel is limited by the key pedestal travel between the rest position and the stop-lock position."

I thought about shaving down the bottom of the keys but for now I think Im going to run it until the perfectionist gets the better of me and the planer comes out.  It has been a really fun project so far minus undoing some of the mods from the previous tech.  Super glue is a mutha.

Offline Tines&Reeds

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Re: How to get more key dip? (Rhodes)
« Reply #3 on: September 11, 2020, 01:10:04 PM »
Seans very last point

3.  Raise the hammer cam stop-lock position by raising the whole action rail.  Shims under the action rail are not illegal.

is the way to go if you want more key dip in general. If you want to fine tune key dip on a single key, you have to shim or shave off the pedestals.
German Rhodes Tech nearby Hamburg / Bremen

http://www.tinesandreeds.com

Offline jwc44

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Re: How to get more key dip? (Rhodes)
« Reply #4 on: September 13, 2020, 05:18:25 PM »
Much appreciated.  I can live with what I have so far.  Replacing the grommets and knocking the surface rust off the tines with steel wool today.  For anyone who is interested Simichrome cleans them up really well.

Offline cinnanon

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Re: How to get more key dip? (Rhodes)
« Reply #5 on: September 16, 2020, 10:20:58 AM »
replaced the back felt

How thick is this back felt? Where'd you get it? Was it thicker than what was there before? Thicker back felt reduces keydip directly.

When I replaced the back felt with a thicker felt, I had to use thicker balance rail felts to get the key fronts higher, and I had to use thinner front rail felts to get the proper key dip.

Also, what is your current key height (to the underside of the front lip)
« Last Edit: September 16, 2020, 10:26:17 AM by cinnanon »

Offline jwc44

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Re: How to get more key dip? (Rhodes)
« Reply #6 on: September 16, 2020, 01:43:43 PM »
Thanks for the insight.  Initially I wanted to use a thicker back rail felt to help with key bounce but that definitely made for shallower keydip.  I have the key dip under control, now its dealing with escapement.  I am making some new shims for the aluminum harp supports as the particle board is a bit too thick on top.