As has been said, the rails in Kawai actions are fixed and the action spread cannot be moved more than a few 10ths of a millimeter. So that's why this spec is not published.
Heavy touch checklist for Kawai actions:
- Regulation is off, especially hammer blow. Should be 46mm. Check jack alignment to knuckles also, makes it feel heavy.
- Knuckle condition. If they have become flat, needle the core felt side to side to bulge them back into round shape. 3 to 4 long needle passes through the core right at the flat area usually does it.
- Wippen cushions have become cupped. I flip the top action over and apply hot 50% isopropyl to the dimples, let them dry overnight.
After these 2 items, I put the action in the piano, close the lid, and go at it with my fists for 10 minutes to settle things down. Then do the regulation.
- Polish capstans
- Polish key pins, apply TFL-50 or your favorite dry lube.
- Dampers have settled down low, raise the levers on the wires to lift at 1/2 hammer blow.
When new, the actions are set for 56grams down weight, and in the aria of 28 - 30 grams upweight. This should not feel heavy, because the mass in the action is relatively low.
You can customize the action to make it lighter by replacing the old tan colored wippens with the new black carbon fiber wippens, which are both lighter and better designed. Makes a big difference - but this isn't the first thing to do! The action should be serviced well
first to work as it was originally, then if the customer wants to take it further call Kawai for the current price on a set of wippens.
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Don Mannino RPT
Kawai America Corporation
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Original Message:
Sent: 09-07-2022 22:51
From: Tim Coates
Subject: Kawai RX3 action spread
Hello Steve,
I have not seen the piano yet and the pianist is complaining of a heavy touch. It is not just her opinion, but another pianist and technician tell her it has a heavy touch. I like to start with some basics, such as action spread. I have seen a lot of Bostons and some Kawais with heavy touches and there are some remedies. I have not seen that many RX models.
Since I will not see the piano until the end of the month to diagnose the issues, I am looking for what I consider some basic specifications. I can't find anything in searches for Kawai. I assume it is 12.5mm or 13.5mm, but some pianos have a little different spec. Or I could just do it the old fashion way and experiment with different spreads.
I'm not saying this piano has an issue with the action spread, but I like to make sure that is in order before I really dig in.
But what you are telling me is the brackets won't allow adjustment.
Thanks Steve for the information.
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Tim Coates RPT
Sioux Falls SD
Original Message:
Sent: 09-07-2022 15:25
From: Steven Rosenthal
Subject: Kawai RX3 action spread
I believe the action rail/brackets are notched such that they can only fit one way.
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
Original Message:
Sent: 09-07-2022 07:52
From: Tim Coates
Subject: Kawai RX3 action spread
Would someone tell me correct action spread for a Kawai RX3?
Thanks,
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Tim Coates RPT
Sioux Falls SD
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