At 10:26 PM +0100 1/2/02, Isaac OLEG SIMANOT wrote: >French polishing = Vernis au tampon yes >the Rubber = le tampon yes >bodying = remplir (with ponce powder and alcohol an a very few varnish) >or may be "faire monter le vernis" Bodying comprises "bodying in" and "bodying up". The first process after any filling (I don't fill), staining and "oiling in" is called "fadding in". Here one uses a well-used rubber that has been thoroughly felted by long use and dried out in finishing. The "fad" is used uncovered so that a good quantity of polish can be applied. No oil is used during fadding in and one works mainly in straight lines. Most of the body thus applied will be cut down almost to the wood, and the purpose is to fill the pores, since "filling" only does part of the job. When the polish has hardened, it is cut down and then "bodying in" begins. The polish will always shrink into the pores, so one needs to build a body that will be sufficient to leave the pores _almost_ invisible. Bodying in is done with a fairly soft rubber and a good quantity of polish is applied. Since the surface is soft, the polish in the pores expands and the rubber flattens them out as it passes, so it is impossible at this stage to get a glass finish, since the pores will show after the body has evaporated and hardened. In the old days, piano parts would be brought to this stage and then laid aside until a few weeks before Christmas, when most sales could be expected. The parts would then be borught out, bodied up and finished, which involves several processes I won't go into. >oil = "graisser le tampon" >the oil used for French polishing is often "oeillette oil", I thought >linseed was too heavy for French polishing. It can be used but I prefer white oil, which is probably what you are referring to. >When I talk about oil base varnish, this is because I was told than most of >the German pianos where finished with this kind of finish (something like >the "flatting" varnish if that name is same in English). Am I wrong ? I >don't know, but I thought that French polishing was mostly on French pianos >(and English ones too, but the way it is conducted possibly be different in >England because the preparation of the support with hot rabbit glue vs. >ponce powder in France. All the German pianos I have restored (and that's hundreds) have been French-polished and most of them well. I think the best polishing was done in England from about 1840 onwards and Broadwood probably had the best polishers ever. Erard, with his factory in London, would also have benefited from this, though Erard's ébénisterie was superlative and never matched by Broadwood. Pumice has always been used in England in the piano trade for the "glass" or "German" finish and at other stages in the work also. I use pumice during the "bodying up" process, when a harder, drier rubber is used. At each "dipping up", or recharging, of the rubber, some pumice is sprinkled in the sole of the wadding. This passes through the cloth with the polish and grinds the surface as it applies the body, so it is putting on and taking off at the same time. I also use pumice topically to deal with small pinholes etc. Traditional English practice outside the piano trade did not use pumice and it is only piano polishers that use this method, which requires a lot of experience. I was taught to finish with "chalk and vitriol" -- Vienna chalk and sulphuric acid -- but I rarely do so now except to keep my hand in; I find burnishing creams are better. >When finish, we use a product called NIKKO to dry the surface and have all >the remaining oil off (it clears the surface too). The same product is used >to renew old finishing, it have some acid and Tripoli powder in it, soften >the surface of old varnish so you can have it shiny again. Do you use this >product too ? I think that is equivalent to the burnishing creams I use, which may be more traditional but probably have similar effective ingredients -- old ale, vinegar etc. :-) > > You can buy ready-made black polish but this is based on "button >> polish" which is a quality I do not normally use. > >Is it what we call Copal or "vernis a mecher" used with a piece of cotton ? >You may pass only once with this quality,and without any oil ? No, that is a varnish. Button polish is what is generally used in the antiques trade here and is yellowish and cloudy with some wax left, but it is shellac. I never use it. >I was guessing that the old pianos black finish was first the wood >tinted black with a natural "bois de campeche" tint (and dichromate >of potassium as a "mordant" agent) this is a little reddish violet >black, is it what you call spirit black ? Probably the same. It's always been called just spirit black here. I must find out what it is because it used to be cheap and now they've changed the name and sell it for 20 times the price in little pots! I use bichromate of potash for darkening and reddening certain types of mahogany. >or is there any other dye (aniline, or alcohol tint, or fushin) you know ? >Is the dye mixed in a large quantity, or a little is enough ? >From memory, I add about 50 grams per 5 litres. It must be good and black. >BTW, do you know a kind of "easy" French polishing called 'Furniclass' ? >and what is the name of the finish where the lac is mixed with wax (we call >that "Mattine" finish) We used to have "Furniglas" and the burnishing liquid that came with these DIY kits was terrific and smelt wonderful too. I think that product is no longer made, but maybe it has just hidden in France. I'd love to get some more of that liquid or find out what they put in it. >Last but not last, have you a good source of bushing actually , Jahn have >only 1.3 and 1.6 mm quality, Renner only 1.2, Kluge actually uses only 1.2 >mm from Renner and I don't have any good source for quality pure wool >bushing felts. Is Fletcher Ok (I guess ....) Fletcher or Heckscher should have more sizes. All these cloths used to be made in England and probably still are, but nothing is quite what it was. I'll have a look in the catalogs tomorrow. I only use the English suppliers for a few things because their prices are just incredible. I get most things from Danielsen in Denmark. Meyne is good but expensive. JD
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