Purpose:
Violin labeled
dated to the eighteenth century, allegedly Polish origin, noticed at least two occasions, one in Glogau and Berlin, the latter in the year 1903.
With label that reads: Jan Dankwart Warsiawiac Year 1750.
Below the label, manuscript, Reprt (Repariert, repaired) F. Ho (ff?) Mann in Glogau
State:
presented multiple cracks at the top, ribs, back and one on the headstock.
Top slightly deformed, deformation increased once glued the cracks.
In this image of the mold, prepared over the top after hitting the cracks, deformations are seen mainly in central and bottom.
Interior lined top center, the original bar and the upper and lower liners vanished.
The lid contained three internal lining over it and keeps lining the bottom edge extends to the center of each of the central edges.
Inside the lid of the central shell, the original bar and the bottom liner vanished.
upper and lower liners were vanished, probably in a post-intervention that introduced so that only parts that remained was the glue layer that once joined the faded area, as seen in the photo above.
The image shows the dark area and the fading tail of the liner.
The cracked outside the region were reinforced linings Picea plates, some of them detached over time.
These cracked, formerly attached, located in part on the pads and continuing in the area free of lining, which houses the reinforcements, were detached on both the liner and in the party without him.
required washing lid and paste all the cracked, for which it was necessary to remove the harmonic bar and linings.
thickness measurement. The gauge shows 0.7 mm in a central area.
After removing the lining, the cover showed minimal thickness to the center, under severe leg of the bridge, 0.7 mm in the bottom of 1.5 mm and on top of 2 mm.
Following the wash, it was necessary to develop a mold for pressing the cover and restore its curvature continuity possible according to its current state.
The most critical problem was presented with the regions of the lid with a thickness that did not guarantee stability.
Establish a priori weights should therefore first be established what thickness? Mentioned by Sacconi, the Mittenwald School or others?
On the other hand the answer is unknown sound of the lid with any them. The thickness of a lid is made according to the response that she shows to carve their thicknesses.
Based on experience gained over many restorations and contact with different thicknesses of tapas, we established the following limits:
Two and a half millimeters at least sufficient to ensure stability of the cap in the central region is subject to greater efforts, the location of the bridge and transmission of sound from this point and the harmonic bar distributes the vibrations across the top. One and a half
mm for upper and lower regions, subject to minimum of effort.
therefore omitted the need to put a lining in the top of the lid, as this region has more than 2 mm thickness, except for a small area of \u200b\u200bless than 4 inches square, opposite to the axis of symmetry of the lid, the upper end of the harmonic bar.
To simplify the process of adjusting liners, two liners were developed as done traditionally.
loosely attached lid on a log to make the mold on them.
In principle, one should not increase the arc of any curve of a top to rectify the mold. The risk to open cracked and glued assembly is cracked or create new large, since it increases the path length outside of the curve.
Therefore, the correction was made taking into account only the continuity of the curve shaped in the mold. There was no rectification to achieve ideal imaginary curve. The objective of the ground was only removed the lid sections sunk by the pressure of the bridge or correct the level of assembly of the cracks on the outer surface.
for pressing the lid was placed into the mold a sheet of medium-thick aluminum, which is embossed with an eraser to remove any wrinkles.
The lid was placed on aluminum and on it, after moisten with hot water (60 ° C) another sheet of aluminum.
Above them was placed a sandbag at 90 ° C and then placed a 2 "to distribute the pressure.
already pressing, were applied to the top table with a hammer jabs, closing slightly presses as the sand is distributed inside the sack, to feel the ribs hard.
cap was allowed to dry for 24 hours.
liners used to cover half of Picea excelsa violin, acquired in 1967, with at least 5 years of drying at the time of purchase. It was the part with the rings closer together which was in existence.
They joined two pieces to make the most of the part with the rings closer.
He placed two to three rings of inclination with respect to the cap.
The liner is placed on your destination and moves, pressing against the cap no more than an inch of its final location.
left block allows this movement more accurately.
the end, the only liner is located in your destination and press, without moving, so that the chalk mark the contact points.
The chalk must check the lining all of the contact surface.
Vista
backing
marked chalk on the whole surface.
First liner with gouge carved
then rubbed with a brush.
liners were cut in conjunction with escarriador finally to have a sound and acceptable cover tune.
The top, having thicknesses equal to or greater than two millimeters, said he was not previously removed the lining.
tones achieved with cap liners were just a bar height of 10 cm.
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