Thanks again to everyone for great input. What a wonderful resource, this list.
Let me resume.
For cleaning Ivory keytops :
1° clean rag under hot water, with soap.
2° baby wipes a bit dried
3° barely damp washcloth with toothpaste
4° Windex diluted in water spray
5° solution of 1/2 water, 1/2 ammonia
6° Dow bathroom cleaner
7° 100 grit sandpaper, solution of 40 % H2O2 in the sun, then fine sand and buffing wheel.
For other keytops :
1° Fantastic applied to the cloth (but features industrial strength perfume)
2° Cory Key Brite
3° 409, Simply green
Special recommandation : keep moisture away from water soluble glue joints.
For key wood :
1° 80 grit sandpaper, one way brushing action
2° scraper or razor blade, used softly
3° disk sander
4° Fantastic (again)
5° rub with 60 grit sandpaper, use felt belts and ivory polishing compound on belt sander.
Thanks again to all. I am sure this helps (me certainly).
Best regards,
Stéphane Collin.
This PTG archive page provided courtesy of Moy Piano Service, LLC