Steve's Corner - Escapement & Strike Line
Escapement is the distance between the top of the hammer tip and the bottom of the tine, with the key depressed. This is the position the hammer falls back to after the tine has been struck and the finger is still on the key. This distance is approximately 1/2" at the low E (73-note) and gradually gets smaller to approximately 1/16" at the highest E. Do not press excessively on the key while determining this distance: you can over-press the key and raise the hammer to a higher position, giving you a false measurement. If the escapement is too large, it will take extra effort to play the piano. If the escapement is too small, the hammer tip will not get out of the way of the tine's first down swing, and a "thunk" or dead sound will be what you hear.
Adjust the escapement by inserting a spacer between the harp support blocks and the harp. Any readjustment of the escapement will change the damper settings, so they will need to be readjusted also.
This subject assumes that the damper action is working correctly and the dampers pull away from the tines to about 1/2".
Strike line (or strike point) is the point on the tine where the hammer tip comes in contact with the tine. The strike point is the optimum point where maximum hammer tip energy is transferred to the tine. It is a distance out from where the tine exits the tone generator (the block). As the tine exits the block it is one thickness, and over the initial 1/2" it tapers down to another thickness. The strike point is past the tapered section.
A setting too close to the taper will not transfer maximum energy and will cause a "thunk" sound. A setting out of the strike line towards the end of the tine will not transfer maximum energy due to tine flexibility, and the "thunk" sound will also be heard.
To set or check the strike line, confirm that the escapement is good and that the hammer successfully strikes the high E note (improper strike line affects the low and middle ranges worst). With one harp mounting screw loosely in place at the high end of the piano, strike a lower midrange key firmly and repeatedly. While doing this, slowly slide the harp toward you and away from you. Listen for the harp location that consistently produces the clearest note. Leave the harp at this location and play more notes (lower and higher). If they also produce a clear sound, this is the best location.
Looking at how the holes in the harp frame line up with the previous holes in the support block will tell you if you are already in the best location. If they don't line up, then drill new holes in the support block to remount the harp. Use the extra holes in the frame if the original location is slightly off.
- Chapter 2:
The RHODES Modular Action
- Chapter 4:
Dimensional Standards and Adjustments
- Chapter 8:
Early Design RHODES Pianos - Action (Prior to 1975)
- Chapter 10:
Early Design RHODES Pianos - Dimensional Standards and Adjustments