Monday, August 29, 2011

Grand Piano Restoration: Colouring, and Tinting

When refinishing a piano, the request is usually made because the clear coat on top has deteriorated to the point where it requires a new surface.  The outside is scratched in many places, or perhaps the outside coats have the appearance of snakeskin, or alligator skin, with the small multiple cracks, or crazing, as it is commonly referred to.

Along with this expected deterioration is the wear on what is called the “colour barrier.” This is the colour that the wood was stained with and forms a type of barrier to hide or change the original colour of the wood.

Any cabinet piece that is considered a “high traffic” area of the piano, which is usually the area where the players sit and operate the instrument, the colour eventually gets worn away, allowing the wood to show itself without colour stain, or finish.

Places such as the fallboard edges, music desk edges, keyboard end blocks, cheek block edges, around the keyboard and pedal set are the most common places to find this type of wear.

So then, along with the request for an improvement to the finish which is clear coat, one must determine what the original colours were, if the finishing request is a return to original colour.

There are specific places on the piano that one can discover the original colours; inside on the cheek past the keyboard end blocks, in the cabinet of an upright, often times the back of the fallboard does not receive any sunlight and a good place to find original colouring; underneath the grand piano on the rail just above the legs attachment; this rail runs underneath the piano and is often a place where you can discover original colour.

Colour stains are straight forward; choose the colour you want, either in oil stain, alcohol stain, or water stains; these are all available today and serve different purposes when refinishing. I choose to use oil based stains that can be wiped or sprayed on. The reason I choose these types of stain is because most of the pianos I refinish here are fairly old; the oil provides the old veneer with a bit of welcome moisture and also raises the grain lines.

This is beneficial to the finished product.  With some oil based colours, it is best to let the oil evaporate off for a couple of days as the lacquer finishes are alcohol based and these two products reject each other.

Water based stains, which were popular at the turn of the last century, are now making a comeback into the marketplace due to environmental concerns.  Water based stains are used much the same as oil based stains.

I find that alcohol stains are NGR stain; non grain raising stains tend to give the appearance of being painted, as alcohol stains are very strong in their pigments and do not allow the natural inconsistencies of the wood to show through.

NGR stains are primarily used for tinting problem areas of wood and can be mixed into the sprayed finish to colour match problem areas that have colour damage as a result of sunlight UV rays or other types of colour damage to the patina of the wood.

With tinting, one must have knowledge of the colour wheel, primary and secondary colours, a full understanding of tint, tone, and shade, along with how colours compliment or split compliment. In other words one must be able to “see colour.”

Without the ability to see colour, one must then attend a finishing supply shop and have the colour matched or purchase an already mixed colour. For tinting, these shops can tint the finish to what you need or give you a recipe to mix with your own colours you have purchased previously.

Here is a photo album of a piano that came in for refinishing. This instrument was completed sometime back, and while it is not the Heintzman presently under construction in the shop, this piano is a good example of the colouring and tinting processes.  

Aside from the damage done to the instrument, I discovered that this one had been refinished improperly and also had long term light exposure, so this is a good photo album to view about refinishing pianos. It demonstrates some of the problems you have to solve to get the instrument looking good once again.

Underneath each photo I have written some text about how some of the problems are overcome.

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