Abel Mahogany-core Hammers fitted to Kawai Grand

Setting up the jig
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Testing the height of the string line
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Measuring the weight.
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The markings for the weight on the lowest notes 57 - 73 - 67 - 63 - 76 (grams).
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The shank-flanges are Renner standard. The Kawai action rail requires them to be 1.5mm shorter.
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It's hard to see in the photo. The original set-up had the hammers leaning to the left in the middle section, and leaning to the right in the alto section.
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Drilling the holes in the new mahogany-core hammers from Abel.
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The new hammers for the end of each section are fitted first.
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The two top sections are done.
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Half way!
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Just the bass to go.
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Generally pianos are designed to have the hammers in a straight line. On this model, the top section deviated slightly such that the top hammers shanks are slightly short.
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Checking the hammer line. Each hammer is glued on and aligned against the straight-edge.
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Checking the alignment of the tenor and alto sections.
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Same
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The bass section complete. The glue needs to dry for a day before the shanks can be machined to be flush.
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Back view of the hammers, showing the extra length protruding.
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I machined the bass and tenor hammers one by one, removing them from the action rail, because of the angles.
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Before ..
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The shanks are clamped together to allow for sanding the whole section.
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 ... and after
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All that remains is for me to make the action work,
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The old hammers were good standard hormbeam-core Kawai hammers, heavily grooved and over-voiced. The new hammers (Abel part no. 222/0) have mahogany cores, giving a warmer more rounded tone, with more possibilites. I have set the angles to follow the string angles very closely. This is closer than originally designed, but requires a little more machining, which is why it wasn't done in the factory. I anticipate that the extra time and effort put into this job will be evident in the resulting tone. I apologise for the extra time, but I am sure you will be happy with the new sound and feel.
 

   

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