WOOD
types of wood used in the construction of string instruments Picea excelsa
• • Wood used for the cover, harmonic bar and blocks.
• Common name: "Pinabete" or "fir."
• conifer which comes mainly from the Alps.
• Acer spp.
• Used to the bottom, ribs, mango and bridge. Using several species of the genus Acer.
• Common Name: Maple or Maple.
• The best from the forests of Bosnia.
• These species, although there are in our country do not have the same physical and mechanical characteristics of European woods, for climatic reasons.
hygroscopicity is the ability of materials to absorb and expel moisture.
hygroscopic materials are wood and horse hair bow.
His reaction to the environment:
If the environment is humid, wood absorbs moisture and hair and expand. If
environment is dry and lose moisture and shrink.
Anisotropy is the property that have certain bodies, namely the dependence of their properties in the direction that they consider.
Wood is an anisotropic material therefore considers three sections with different properties:
• radial Court, the areas with the rings perpendicular to the surface of the wood.
• Tangential section, the areas with the rings parallel to the surface of the wood.
• Cross-section: the surface perpendicular to the grain of the wood.
• Tangential section, the areas with the rings parallel to the surface of the wood.
• Cross-section: the surface perpendicular to the grain of the wood.
Wood shrinks and expands less radially in tangential direction.
Therefore, most of the parts has a radial cut.
Disposition of funds in the trunk
• The trunk is cut or slit into segments preference for the tops or bottoms of the instrument PREPARATION OF SEGMENTS FOR THE DEVELOPMENT OF TAPAS
• Each segment is divided into two sides together for wider.
• Each segment is divided into two sides together for wider.
The process of joining two pieces to get a cap aims to:
• Use smaller diameter logs.
• Achieving symmetry in the structure of the top and bottom, for the provision of the Rings and other physical properties of wood are repeated in each half.
• Achieving symmetry in the structure of the top and bottom, for the provision of the Rings and other physical properties of wood are repeated in each half.
GLUE
Cola
• The glue used is rabbit skin glue, fish or cattle.
• The tail also is hygroscopic. With moisture softens and the instrument is off. • An assembly
well done, with the tail of good quality can last over 200 years without a break, if kept in good condition.
Cola
• The glue used is rabbit skin glue, fish or cattle.
• The tail also is hygroscopic. With moisture softens and the instrument is off. • An assembly
well done, with the tail of good quality can last over 200 years without a break, if kept in good condition.
MOLD
• About the mold is made ribbing.
• The shape of the cap depends on the developed ribbing.
ribbing
Carving blocks
Carving blocks
• About this mold stick six blocks.
• They have to be carved on them to fix the ends of the ribs.
• The mold is removed, after hitting the rib to bottom of the instrument.
Bending ribs
• The ribs are attached to the wall covers.
• tables are made with thin (1.5 - 1.7 mm) of maple, bent with heat and humidity, each attached to two blocks.
• Its height is critical to establish the volume of air needed for a good sound of the instrument.
• Its height is critical to establish the volume of air needed for a good sound of the instrument.
• The ribs should fit well into the mold and blocks.
• From the outer edge traces the outline of the tapas.
ribbing over
• Once attached the contrafajas, correcting the ribbing on the edge of contact with the lids, then put on the bottom and lid and trace its outline on them.
Taller de Tapas
Cut the outer curve
• Covers cut in outline
• It is carved with gouges its curvature first, then with small brushes and finally with a few sheets of steel.
• Once the exterior surface with all its details, the interior is carved in the same order, up to thicknesses required for each piece.
Carved interior
• When carving inside, bottom and lid are drumming events for detecting the loudness and pitch. Modes 1, 2 and 5 must be tuned in octaves.
• It is the most difficult process is not always fully achieved. This work will be the sound quality of the instrument.
• It is the most difficult process is not always fully achieved. This work will be the sound quality of the instrument.
THE EFES
Locations efes
• The top is balanced on the line form the inner notches of the f holes.
Court of efes efes
• The first cut with hacksaw and then gives the final form with a knife.
• From the location of the f depend on the position of the bridge, the soul and harmonic bar.
• The first cut with hacksaw and then gives the final form with a knife.
• From the location of the f depend on the position of the bridge, the soul and harmonic bar.
bracing
Court and harmonic bar adjustment
• The harmonic bar is a piece of spruce, 11 to 12 mm thick, which runs along the top, next to the EFE, the side of the bass strings.
• The harmonic bar is a piece of spruce, 11 to 12 mm thick, which runs along the top, next to the EFE, the side of the bass strings.
Bar Features harmonic
• Reinforce the lid lengthwise, harmonic, and reinforces inhibits serious resonances.
• It has the same thickness as the soul, its height is twice its width and is 2 / 9 shorter than the top.
• It is cut according to the internal curvature of the lid.
• The curvature of the bar should be more pronounced than that of the lid.
• You must dovetail with the cover, without much pressure.
• After the punch, its final form must meet the same standards of sound and pitch to the top without Fs and no bar. HEAD
• Reinforce the lid lengthwise, harmonic, and reinforces inhibits serious resonances.
• It has the same thickness as the soul, its height is twice its width and is 2 / 9 shorter than the top.
• It is cut according to the internal curvature of the lid.
• The curvature of the bar should be more pronounced than that of the lid.
• You must dovetail with the cover, without much pressure.
• After the punch, its final form must meet the same standards of sound and pitch to the top without Fs and no bar. HEAD
• Product of the XVI century, head, coil or spiral, sometimes carved in the shape of a human head is an ornament that crowns the instrument.
• His carving requires systematic work. Its finish is artistic stamp of the manufacturer.
Antonio Stradivari, the head of a viola da gamba soprano
Construction head
profile of three stages in the process of cutting off the head and socket
Side view of three stages in the process cutting socket head and
MANGO
The frame of the handle to the box
• The handle is fixed in the upper block of the soundboard.
• All walls of the heel is placed in the block must match perfectly with the walls of the box that receives the heel.
• The heel is painted with chalk to verify the union of the surfaces on the box.
Features to be covered by inserting the handle
• The handle should be:
• Focused to the axis of symmetry of the top 20 mm
• Excel in the cello and violin between 7-10 mm in on the edge of the lid.
• The distance from the edge of the upper cap nut must measure 280 mm in 130 mm cello and violin.
• The projection of the fork mounted on the handle should measure 77 to 80 mm in the cello and violin 26-29 mm at the site of the bridge.
• All these factors are controlled through the cut of the box. After gluing the handle can not be corrected position.
VARNISH
Features to be covered varnish
• While any coating inhibits the loudness, it becomes a necessary evil to protect the wood, while providing beauty and personality to the instrument. • Must meet
certain physical properties of hardness, flexibility, transparency, adhesion and mechanical strength.
• Consists of resins, dyes, vegetable and animal.
• Each resin has different properties.
• No resin alone has all the properties that require an instrument. So
• Prepare a mixture of various resins that, overall, result in the glaze with the properties that the instrument requires.
• Prepare a mixture of various resins that, overall, result in the glaze with the properties that the instrument requires.
However, each coating is different, p. eg. softer or harder, so cleaning should be done according to the consistency of varnish-specific instrument.
musician is recommended to only perform cleanup with flannel cloth after using an instrument. More thorough cleaning should be performed only by a professional.
FINGERBOARD
Tuning Fork
• Fingerboard and bridge should form a unit to facilitate the musician play the instrument with as swiftly as possible.
• The pitch has a transverse curvature that is designed according to the curvature of the bridge.
• Longitudinally, should be similar to a concave shape that the string when it vibrates
• This form allows the strings are as close to the fingerboard, giving the musician the best possible comfort for their implementation.
. 
concave cello (and also violin).
form of a cross cello fingerboards.
Footprints use in a violin fingerboard.
PINS
Features
• The plugs have a tapered pin, which must be perfectly round.
• They are inserted into a hole that penetrates both sides of the headstock.
• These holes must have the same taper the pin of the plug and also be perfectly round.
• Over time, due to the difference of shrinkage of wood (in the radial and tangential), pins and holes become oval.
• It is therefore necessary to change the plugs periodically, after grinding the holes in the headstock.
• A smear plugs are a special paste that serves as a "lubricant abrasive", allowing the plug turn easily and stay in the required position.
Pins in good condition should show equal brightness around and on both points of where they are rotating in the socket. If irregular, is necessary to correct the holes of the headstock and change the plugs with new ones.
NO correct position of the pins in headstock. The dotted line touches the rope intermediate pins. To tune the strings of the middle pin, out of tune the string above the plug.
correct position of the pegs on the headstock. The red line in the string does not touch any pins between.
SOUL
Definition and characteristics
• The soul is a wooden pin inserted between the top and bottom, parallel to the ribs.
• Supports the flip-side of the strings.
• Because of its position and the voltage that is inserted substantially influences the sound of the instrument.
• The ends of the soul which are in contact with the bottom and lid must be cut according to the respective curves (bottom and top), so your contact is complete in all its surface.
soul ends
theoretical location of the soul with respect to the bridge
• The soul must be offset by half the diameter of the bridge to the tailpiece.
• The distance from the edge of the "efe" (on the treble strings) the soul must be the same distance as the edge of the "efe" (near the bass strings) to the harmonic bar.
final location of the soul
• cello's soul can move in all directions, no more than 2 mm in this position until find the place that gives the best sound of the instrument. In the violin 1 mm.
• Shrink covers can cause the soul over tighten the lid and the background.
• This stress can have an impact on the sound.
BRIDGE
• Shrink covers can cause the soul over tighten the lid and the background.
• This stress can have an impact on the sound.
BRIDGE
theoretical position
The bridge should be, with the surface facing the tooth, perpendicular the edge of the lid.
• The song of the cello bridge, over which the strings are placed, is round and has an approximate thickness of 3 mm, 1.3 mm on the violin.
• The bridge is positioned on the line connecting the inner notches of the f holes.
• The surface of the bridge overlooking the ridge is displaced from this line towards the ridge 1.3 mm to 3 mm in violin or cello, corresponding to the thickness of the upper edge of the bridge over which the strings rest.
• The bridge is positioned on the line connecting the inner notches of the f holes.
• The surface of the bridge overlooking the ridge is displaced from this line towards the ridge 1.3 mm to 3 mm in violin or cello, corresponding to the thickness of the upper edge of the bridge over which the strings rest.
• The bridge must be centered over the fingerboard and on the inner edge of the Fs. If both do not match, the handle is inserted outside the symmetry axis of the instrument, or Fs are not located symmetrically with respect to this axis.
Jumper setting
For the transmission of vibration of the strings to the top to be effective, requires that the surface of each leg snaps with the surface (curve) of the lid. This work is done with a knife.
By tightening the strings on the bridge of the cello, the pressure tends to open the legs of the bridge.
• Therefore, the bridge of the cello has to comply with a cross to open the legs ("legs") to the position in which the strings are strained. The bridge of the violin does not need this stress, since their "legs" are very short.
natural deformation of the bridge
The bridge should be completely straight on the side of the ridge to ensure maximum transmission of energy from the strings to the top. cords tend to spread over time.
Returning to tune the strings, pull them slightly over the bridge towards the fingerboard.
Therefore, the bridge tends to bend the pitch as time passes. A bridge bent
works as a cushion and absorbs the energy that give the strings to vibrate.
It is therefore necessary to straighten the bridge regularly.
Straighten the bridge
• With the instrument to support the button or pin into the abdomen, placing the indices between 1 st and 2 nd and 3 rd and 4 th strings, the fingers underneath the strings and the thumb on the surface facing the tailpiece, the bridge is pulled to straighten the ridge.
• The notches where the strings rest should be graphite (pencil).
Protection instrument with environmental moisture
• The humidity in the air affects the wood of the instrument and thus in its loudness and stability.
The hygrometer
• The hygrometer measures relative humidity (RH) present in the air.
• Relative Humidity is the amount of vapor that exist in a given volume of air at a given temperature, compared with the total volume of vapor that air can absorb at that particular temperature.
• The humidity in the air affects the wood of the instrument and thus in its loudness and stability.
The hygrometer
• The hygrometer measures relative humidity (RH) present in the air.
• Relative Humidity is the amount of vapor that exist in a given volume of air at a given temperature, compared with the total volume of vapor that air can absorb at that particular temperature.
• Relative Humidity for retaining a string instrument is between 40% and 60% RH.
• The ideal relative humidity is 60% RH
Care humidity instrument with
• To protect the instrument, the user will not be exposed, as long, to:
• Drafts
• Excessive heat, and within the trunk of a car in the sun.
• direct rays of the sun.
• High humidity (above 60% RH).
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