To grandpa Jianzhong Wang (1927-2018), veteran of many battles, whose spirit was around during the process, who taught his children and grandchildren to be honest, and hard working.
This piano hasn't been serviced for some years. One would assume dust bunnies gather on keybed and enclosed pedal area. Carefully exam the piano, see how parts are going to be taken off. Every piano is different. If needed, take pictures of disassembly process. Remove keys makes it easier for a thorough cleaning.
The action is redesigned by the shop owner Mr. Jude Reveley. The key height is increased to 66mm from about 64mm while the fallboard still fits above keys under stretcher. Somehow after first pass of key leveling, they are pivoting sluggishly on balance pins. But balance holes were loose enough before the top stack is on. The problem is that, with the increased key height, the balance pins are leaning too much forward in balance holes, binding the holes as well. By tapping them back, the keys are eased.
This is a tribute to all my mentors from North Bennet Street School, Mr. David Betts who contributed his life to this trade and his beloved apprentices. Today is Mother's Day. Best wishes and lots of love to Debbie and Emily, my caring mentors who support us from the beginning and there seems to be no end for it.
This process is taken from two backaction replications. Personally, it is still a new skill to be refined. Compare to WNG Aluminum backaction, we found Renner's wooden system more consistent and with less flaws.
Lay out the parts, check if anything is missing from the box, and read assembly process from manufacture. First, determine location for the first underlever. On old damper tray, measure distance from the bass end to center of note 1 underlever, transfer measurement onto new damper tray. Again, on old tray, measure distance from bass end to bass side of note 1 underlever, transfer on to new tray. Position new underlever flange onto new tray, determine the most accurate position according to the two marks, then mark it down. The new damper tray comes with the screw line grooved. Use a pencil to mark along the groove to make it more visible for easy working process.
When damper wire is not riding against guide rail bushing (not touching one side of the bushing), the damper head is likely to shake or move irregularly going up and down. This can be adjusted in the piano by bending damper wire. The bottom bend is for spacing, the top bend is for squaring. The top and bottom parts of the wire shall be parallel. The video is what I learned so far these years. As time goes by in the future, hopefully personal damper skill could improve.