The rim braces are glued in three layers, two of which on the outside are made of first class pine and the one in the middle is made of red beech for extra stability. One end of each brace is mortised into the inner rim, the opposite end of each brace is fitted into the back rail. To further secure the braces and rim, the braces are screwed to the rim and keybed and consoles are glued and screwed to the rim.

All models have four or five lengthwise braces and a crosswise brace made of red beech, 40mm (1½") thick, mortised and glued to the braces. The number of length braces and the measurements of the brace material is listed below:

Model: mm / number
1: 65x120 / 4
2: 70x110 / 5
4: 65x110 / 4
6: 65x110 / 4
10: 65x110 / 4
11: 65x110 / 4

Pinblock
Extra select red beech cut into layers of 2mm is glued crosswise together in 16 layers using water resistant glue, reinforced with a layer of quarter-sawn red beech. The thickness of the pinblock is 36mm.

Soundboard and Ribs
The soundboard is made of clear, quarter-sawn solid spruce. It is varied in thickness by reason of acoustical design. Careful manufacturing assures the greatest responsiveness due to an optimal ratio of elasticity to density. The ribs are also of select quarter sawn spruce, graduated in width and thickness and feathered for flexibility and frequency response. The number of ribs used is:

Model: number of ribs
1: 17
2: 13
4: 13
6: 12
10: 11
11: 11

The ribs are mortised into the inner rim and glued to the soundboard with water resistant glue. The whole soundboard is coated with a special kind of varnish. Only fine grained, white, well-seasoned spruce which originates from the Eastern Alpine region is used in the production of Bluthner soundboards and ribs.

Bridges
The bridges of a Blüthner grand piano are handmade of solid maple, with a reinforcement in the treble, fitted with transmitting bridges where necessary. They are carved and fitted with bridge pins made of steel.

Strings
The treble strings and the core wire are of highest grade, strong, elastic steel wire. The high precision in production avoices differences in diameters, which ensures a clear tone without any falseness. The wrappings of the bass strings are of solid copper, the core of hexagonal dimater.

String Plate, Tuning Pins and Aliquot System
The string plate is cast in special iron which can support high tensions but it has also a damping effect, remaining inert to string vibrations. Its form is carefully calculated and specially designed for each model. The firm's name is cast into each plate. All agraffes are of brass and threaded securely into the plate.

Chromium-plated tuning pins of special steel, multiple threated, are used. A fourth string for every note in the treble section, which runs parallel to the normal strings, passes over the bridge but is elevated where the hammer strikes. This stirng picks up the vibrations sympathetically and enhances the overtone spectrum of the instrument.

Action and Hammers
The action is made by Renner according to measurements provided by Blüthner. This ensures a smooth and fluid touch. All parts are made of select sound hardwood, free from imperfections. All critical action felts and cloths are made of 100% wool, with manufacturer's moth-resistant treatment, and are equal to the highest felt and cloth standards. Centre pins are of nickel silver. All centre-pin bushing is pre-shrunk. The actions of all Bluthner grand pianos are designed and thoroughly tested for optimum performance and longevity.

The hammers are a fundamental part of the strument which contribute substantially to the unique Bluthner sound. Crafted from the finest felt, arched over a core of walnut wood and individually voiced to perfection, the distinctive Blüthner hammers stimulate the purest vibrations of the strings.

Keys and keybed
All 88 keys are made of spruce, the sharps are made of ebony and the white keys are covered with acrylic. It is also important that sensitive key balancing is performed to exacting specifications that ensure ease of reptition and control.

For the keybed, select spruce is glued together in several layers to a total thickness of 42-45mm, depengin on the size of the instrument. Red beech is inserted where the attachments of the legs are situated.

Pedals, Casters and Hardware
All grands are equipped with three pedals of solid brass. They serve for shifting the keyboard, sostenuto and sustaining. The casters for all models have swivel stems and solid brass wheels 3-7cm wide according to the size of the instrument. The concert grand casters have a swivel stem and special double wheels on brass bearings, with a locking mechanism included. All external hardware is of solid brass.

Chipping and Tuning, Regulation
The pianos receive a sufficient number of chippings and tunings consistent with the highest piano manufacturing standards. The action is fully regulated during the period fo settling of the entire piano. Before voicing, the piano is given a final regulation. The hammers are carefully tone regulated by a master craftsman to obtain a uniform tone level from note to note.

Seasoning and Settling of Piano and Action
The pianos are placed under moderately fluctuating temperature and moisture conditions until the various elements season and settle into a stress-balanced piano unit.

Leg and Lyre Construction
Legs are made of glued pine, twice veneered, mortised and wedged into the leg bracket, which is made of red beech. The lyre is also made of red beech, all parts firmly wedged together.

Fallboard and Lid
The fallboard is of 12-ply construction with a core made of pine. The lid is made of several layers of veneer, cross-branded, and with hard maple as the final covering.

Finish
As far as necessary, all cases are stained, multiple lacquered, rubbed and polished by hand.

Cores and Glues
All lumber is seasoned for several years. Only then is the lumber kiln-dried to a moisture content between six and eight percent, glued with moisture resistant glue and properly seasoned after gluing. Moisture resistance glue is used except where the size or construction of the part makes this impractical or undesirable.