Touch Weight Measurements

The left chart shows down weight and up weight measurements for the bass section of a mid 70’s vintage Steinway model M. After traditional regulation and lubrication, this action remained heavy, despite having 5 leads in each key . The right chart shows the same action after installation of a TouchRail with down weight measurements readjusted to 52 grams. The TouchRail produces a lighter, more consistent touch response

This graph shows how the TouchRail compares with added lead weights when reducing down weight by 10 grams. Key resistance has been measured at several points along the keystroke. From left to right, each line includes:

1. Rest position down weight
2. Down weight just before escapement
3. Low key return force *
4. Up weight

The dotted line is the original key. The Black line shows the same key with added lead weights. The green line shows the original key with added TouchRail (no added leads). In the two lower lines, initial down weight drops equally by 10 grams. But as the key travels downward, (moving from left to right in the graph) the TouchRail preserves important low key measurements.

The TouchRail key feels lighter than the original, and more responsive than the lead loaded key.

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