Grand Regulation – part XXV

Step number 38. Check gram weight resistance all 88 keys (continued) 

The proper method to check the gram weight resistance of the keys is to either block up the dampers if the action is in the piano, or to remove the action to a bench. All repairs and regulations should have been performed to the action mechanism. I like to start at one end of the keyboard, say at A#1, and work up chromatically doing the downweight measurement on every key.

On a typical grand, the proper downweight should be somewhere in the mid 50’s for the lowest notes gradually decreasing to the upper 40’s for the top notes. If the downweight for a specific key is within an acceptable range, like 54 grams for note number 10 in the bass, I’ll pass over that key without making any chalk marks on it. If the downweight is something more like 60 grams, I’ll chalk exactly that number on that key. Once all of the downweight measurements are taken, I do the same for upweight. Again, chalking only those  keys which are out of range. The proper upweight should be 25 to 30 grams less than the downweight. That is, if the downweight was 50, the proper upweight should be 20-25. With a little practice, taking these measurements goes rather quickly. My system is to mark downweight behind the key buttons, upweight in front of the buttons. When finished, all keys out of the proper range can be analysed at a glance. Try to be very accurate when taking these readings. Rarely should a key be chalked for a wrong downweight without also showing something wrong with the upweight, and vice versa.

All measurements should be taken to the nearest gram. Using the downweight as an example, the key may not go down at all with 49 grams of weight, but when another gram is added, the key goes down very slowly. A light tapping on the keyframe to aid the key in going down. is acceptable. Record the downweight for this key as being 50 grams. Likewise, in doing the upweight, the key at the point of escapement may not come up with 26 grams of weight on it. But taking one gram off, the key may rise slowly. A record of 25 for the upweight is correct for this key.

All measurements should be taken to the nearest gram. Using the downweight as an example, the key may not go down at all with 49 grams of weight, but when another gram is added, the key goes down very slowly. A light tapping on the keyframe to aid the key in going down is acceptable. Record the downweight for this key as being 50 grams. Likewise, in doing the upweight, the key at the point of escapement may not come up with 26 grams of weight on it. But taking one gram off...

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