Zorba's "Secret" Piano Page
De-bushing the keys at last!
30 September 2006
Table all setup for re-bushing project...
Light dimmer as temperature control for electric bushing cloth removal tool.
Applying water to aid dissolving the ancient hide glue...
The electric tool causes the water to flash into steam...
Enabling a clean cloth removal.
Close-up of the electric tool.
Often, the cloth comes away and sticks to the tool, making removal very easy!
A Spurlock .047" sizing caul is immediately installed upon successful cloth removal...
For both front and center bushing holes.
Halfway there! Keys laid out in the library.
Today I removed the cloth bushings from half the keys - actually 45 keys as I had 90 of the Spurlock sizing cauls. I got into a rhythm after I had done a few keys and learned how to do it. A few points on this procedure:
- Most pros wouldn't do it this way - s/he'd line all 88 keys up in a key clamp and most likely use a fabric steamer to steam away the felts. Much faster, but also takes much more experience to avoid over-steaming the keys and causing all sorts of lovely problems like warping, loosening ivories or buttons, etc. But for an amateur like myself, this seems best to me!
- The Spurlock sizing cauls are an optional step. I found out about them in my research on the 'net - they help the wood, dampened by cloth removal, to dry to a uniform size and shape. Seemed reasonable to me. Then my tuner, the "Piano Smith" also recommended I use them. That sealed it!
- I found that pressing fairly firmly right on the top of the cloth as the glue softens seems to work best, the old cloth comes away stuck onto the electric tool.
- Stubborn stuck to tool cloth can be scraped off with a knife. Stubborn stuck to key cloth can be aided with a bit more water and gently working the tool between the cloth and the wood.
- Front rail bushings came away far easier than center rail bushings - at least on my piano. I think its because the center rail buttons (where the center rail cloth is glued) are made of a different wood than the main key-stick.
- For Goddess's sake, don't buy the $80 temperature control unit sold to control the electric bushing cloth removal tool. A $17 "table top dimmer control" from the local hardware store works just as well for this, and any resistive load up to 300 watts. In my case, adjusting the dimmer to about 50% seemed to work well.
I'm not sure what comes next - I can either start installing the new bushings on the keys that have already been de-bushed, or finish de-bushing before I start with the new. I'll figure that out in the next week or so!