In our Workshop we do indeed use many machines that work with modern technology like table saws in 4 different sizes, big and small bandsaws, different kinds of sanders etc. but for certain jobs we need traditional tools that have a very important function.
One of them is this original 19th century bowdrill from Georg Buck which is essential for drilling holes where one needs to feel the process. An electronic device like Dremel can not do the job with the accuracy of this non-electronic traditional tool.
Another very special tool ist this unique replica of an original French ca.1845 ''Hammer felt covering machine''.
Only 2 other workshops worldwide have their own copy of this machine which lays in the depo of the ''Citte de la musique'' in Paris!
Piano makers like Pleyel, Erard and others used to spend a lot of time training their craftsmen which took him a lot of effort and time to cover the hammer-heads by hand properly.
They used such an instrument to make it possible to do the job within a few hours with the best results.
There are several lead weight plates which give more tension to the jaws pulling the hammer-head felts properly, equally and considering how much tension it is needed to pull different felts with various thicknesses in different registers.
Winding machine for making over-spun strings. Made in Germany ca.1930 by Peter Lechner.
This very well made and updated machine does of course work with a 3 phase motor with 3 variable speeds which works like the old traditional ones but the spindle turns with the help of electricity instead of someone turning it like in the old days.
We added a long ruler to it with movable signs that help us easily mark the over-spun era.
The lower speed helps us make open-wound strings (with larger pitch) without the stress of a modern piano winding machine (which can not work properly without being updated to serve as an older type for older period pianos).
The adjustment possibilities of this machine are of great help for all types of clavichords to square pianos and romantic grand pianos' bass strings.
A tool we made in our workshop that serves us for making the string loops (string eyes) for thinnest clavichord strings up to thickest ca.1850 pianoforte strings with ease. One can make tools out of the most worthless pieces of wood but one can make beautiful tools. Beauty gives the craftsman more desire and energy to work.
Preparing the surface of the old furniture (in our case mostly historical pianos that have beautiful veneered furniture) then varnishing and polishing with traditional (18th century and/or early 19th century) recipes is an important part of our restoration work.
Also finding matching veneers to damaged or missing parts is a very difficult job which makes it a lot more difficult than making new instruments.
Veneers should be cut from other furniture that could not be restored to save/serve the other ones. For example
for finding matches for an 18th century English square piano one can hardly find a matching mahogany from an 1860s mahogany. It must be from the same period to be able to match it professionally.
One of the most important parts of the historical pianos' restoration is the releathering of the top layer of hammer-heads in the proper way by hand but even more important than that is the leather of choice!
The texture, color and more important: thickness and tanning are very crucial in the way the historical piano will sound.
The bigger part of the job had already been done by the maker some 200 years ago and the task of the restorer is to conserve as much as possible, repair everything that needs to be repaired properly (leaving the rest as it is) but when it comes to the sound it is the leather that plays the most important role for the restoration.
Other more important factors like the craftsmanship of the maker, soundboard's wood, design of the whole instrument etc. are things that have nothing to do with the restorer but the maker in the first place.
The leather on the other hand is the thing that can make the piano sound beautiful or dull and boring to our ears. (or too dry and sharp as it is thought to be ideal for 18th century pianos, wrongly!)
About half of the leathers we have in stock for dampers, hammer-head leathers of all kinds of fortepianos and other purposes.
Not only the leather but also the cloth we use is a reproduction of the originals the old piano makers used.
For various reasons like the appearance but also practically usage of the proper cloth we do not use the common practice of modern piano makers which are modern production of thick felts or other synthetic materials.
The thin woolen cloth we use for action parts are in fact the same material as Viennese moderator cloths (which were made in a traditional way from 100% wool and not to be compared with the texture of felt that was never used.
The closest of what one can find today to the original Baumann Action cloth, same texture, same color and same thickness.
Different kinds of the reproduction of traditionally made woolen cloth with different colors and thicknesses.
Choice of glue is also very important because if we do not use animal glues
not only the job is then not reversible
but also it will not have the strength we
look for structural work.
PVA glues (according to the fabric itself, like Titebonds!) are not good for stressed parts or structural work.
Even the chemical so called ''fish glue'' which can be used for small jobs is too weak for structural parts.
Nowadays we know the strengths of these glues.
Fish gelatine (which was also used in the 18th century by fortepiano or harpsichord makers but also much before) has a strength around 150 bloom. Rabbit skin glue or Hide glues are also very good glues. Pork gelatine has 300 bloom while fish glue for cold use has less than 50 bloom! these weak glues soon or late will react to moisture and heat. The wrest plank can move, the bridge can lift up and other stressed parts can also show weakness and loose after some years while something like the fish gelatine which is also reversible is very steady against the heat or moisture.
You can see photos of some other beautiful and handy tools of our workshop down below.
Custom made Punch
for Harpsichord jack tongues
Handful old bench Drill
In this profession one can not be only a craftsman like a good woodworker but without having knowledge about the history of woodworking, materials (like pigments, dyes etc.) and historical keyboard's construction and action.
We do not deal with one kind of instrument (like the modern piano makers do) but we deal with a wide range of nearly all kinds of clavichords, harpsichords, square and grand pianos, tangent pianos, pantalons and more!
Each country had its own style like the English, French, Viennese, German and Italian.
One can learn a lot from the published books and articles (especially the latter that is not free on the internet) but also a competent restorer needs a big photo archive of his own work but also from others.
For many restoration projects, one comes across some question marks that can be answered only through the help of colleagues or collectors who have or had similar or sister instruments that could be compared but also could help the restorer to make the missing parts that are available and are original on the other instrument.
These are among the most difficult parts of our job because most colleagues or collectors do not feel the urge to help each other having access to this knowledge that is neither free nor accessible nowadays and probably will not be in a near future.
But we are extremely thankful to the one and only Christopher Clarke for his generous support and endless hours of help through ages.
And here are some of the Radbon Workshop's photos of the restoration work.