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Author: Subject: Silk Oud Strings - Making Sense of the Historical Data
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[*] posted on 8-31-2014 at 05:32 AM


If Spain was once the source of high quality lute bass strings this situation did not prevail far into the 16th C as the ruling government embarked upon a campaign of expelling Muslims and Jews - groups with expertise in the main agricultural activities of the country and their associated trades (wool and silk). The silk industry in Catalonia was primarily in the hands of Jewish artisans. The eventual decline of these industries in 16th C Spain was further reinforced by application of punitive taxes.
Barcelona in Catalonia was by then producing a reduced range of products including silk trimmings, and other clothing accessories such as braided cord.

We know that many of those escaping the Inquisition were evacuated in 1492 by the Ottoman naval fleet operating in the Mediterranean to be resettled in areas of the Ottoman Empire under the Sultan Bayezid II where their expertise in many fields (including sericulture and silk fabrics) contributed to the economic development of the Empire.

Italy and France had also established their own silk industries - the main centre in France being Lyon. By the late 17th C some of the best bass strings (for 11 course lutes) were made in Lyon (called 'Lyons') as well as those of Italian manufacture. There were also mid range strings known as Venice Catlines.
Nothing is known about Catline strings except that they were 'smooth and well twisted' and elastic enough to work - so were presumably of some kind of roped construction as well as being loaded with metal or metal salts to increase their specific weight. It is assumed that these strings were made from gut but they could just as well have been made from silk - of braided construction for maximum elasticity and a smoothness not to be found in a lumpy roped construction.

An earlier version of bass string is the 'Gansar' mentioned in the Italian 'Capirola' manuscript (c. 1520) as well as later by Dowland (1610) who describes them as 'a kind of strings of of a more fuller and larger sort'. Nothing more is known about this kind of string but Mimmo Perrufo, some years ago, suggested that this string may have been so named because it was like a flexible French decorative cord called a 'Ganse' used in the clothing trade. The Ganse was a small diameter cord of braided gold, silver or silk thread - not a twisted rope construction. There is no mention of gut strands being used in the manufacture of Ganse cords.
Assuming the Gansar string used by Capirola was for his lowest sixth course (he does not say that it was) then - with octave course pairing - it was still good enough acoustically to be tuned down a further two semitones (as it was for some of the pieces in his book of tablature). Re-tuning the 6th course is something of an inconvenience for the player and perhaps led to the adoption of a seventh course tuned two semitones below the 6th course? However it does indicate that string technology had by then advanced sufficiently for the basses to be tuned lower than the 6th course limit for plain, unloaded gut or silk strings with no significant acoustic penalty.

As mentioned earlier in this thread(!), making braided cord of silk is an ancient craft practised by the Chinese and Japanese - crafts that are still popular today - and is associated with clothing and other decorative applications. This popularity together with the invention of modern high speed braiding machinery means that small diameter braided cord (Chinese Knotting cord) is readily available at relatively low cost in diameters ranging from 0.4 mm to 2 mm or more - a range of diameters making the cord suitable for those wishing to experiment with braided instrument strings. Another source of low cost small diameter braided cord is fishing line available as plain braid (with or without a filament core) and also loaded with a heavy metallic core. The majority of these cords use synthetic filament such as nylon for braiding although braided silk fishing lines are made but are very costly.

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[*] posted on 9-3-2014 at 04:53 AM


Author Luca Molà in his book 'The Silk Industry of Renaissance Venice' provides a well researched, detailed account of the development of the silk industry in Italy and the rest of Europe.

The Italian silk industry - for centuries a major industry in the peninsula - was established like that of Moorish 'Spain' by the Arabs and Jews around the 9th C. By the late 14th C the weaving of silk fabric was confined to the cities of Genoa, Venice, Bologna, Lucca and Florence in the North. Other towns such as Pistoia, and Livorno were later to become silk production centres. The attached map of Northern Italy shows the main silk producing area

The main product of the silk industry was silk fabric the production of which was divided into specialist activities - silk farming, silk reeling and spinning, dyeing and weaving. The best quality silk fabric was often interwoven with gold thread. A secondary but significant part of the industry often carried out by family concerns involving women in particular was the making of silk accessories for clothing - French 'passementerie' - which including braided cords or 'ganse'. This was the trade not only of silk spinners but also the associated trade of gold and silver thread spinners - all part and parcel of making decorative braid.

A significant part of the Venetian silk industry - apart from the manufacture of costly silk fabric woven with gold thread - was in the production of silk trimmings and 'passementerie' for clothing.

So what might be the connection with lute bass strings of the 16th and 17th C?


[file]32471[/file]
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[*] posted on 9-3-2014 at 05:19 AM


Italian artisans of the silk industry were employed in setting up operations in Lyon, France in 1536 then to become a major centre for the manufacture of silk products.

Germany was a latecomer to the silk industry - established during the second half of the 16th C. in cities such as Nuremburg and Frankfurt.

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[*] posted on 9-3-2014 at 10:59 AM


So what did the writers about the lute in the 16th C and 17th C have to say about their lute bass strings. Not a lot.

Italian lutenist Vincenzo Capirola (c 1520) used gut trebles that suffered intonation problems due to their natural taper but less so the strings made in Munich, Germany. He mentions that the intonation problem was less with thinner strings than with thicker strings and then mentions a string called 'da ganzer' where the problem was even more acute. As mentioned earlier in this thread a 'ganse' was a braided silk cord used to decorate clothing. Not only does this suggest that Capirola's 'ganzer' string was large in diameter but that it was of roped construction for the necessary elasticity for use as a bass string. He does not say where the strings were used but Dowland at the beginning of the 17th C does - 'strings of a more fuller and larger sort than ordinary which we call Gansars. These strings for the sizes of the great and small means (4th, 5th and 6th courses) are very good'. Neither Dowland nor Capirola say where the 'Gansar' strings were made or from what material.

Let's speculate and assume that these strings were made not from gut (as invariably assumed by present day string makers) but from silk braid with some kind of binder surface coating (glue?) rubbed in as protection against wear and to provide a consolidated smooth surface. Such strings would most likely have been made by artisan silk spinners.
A similar larger diameter braided silk cord but with a spun central core of silver or gold - with its substantially increased specific weight and elasticity would have made good bass strings for lower pitched courses (7th to 11th) on lutes. These basses were called Catlins and - if constructed in this manner -would again have been made in and exported from the silk producing regions of the world.

Robert Dowland (1610):
Gansars has already been mentioned above. Dowland goes on to say 'there is another sort of the smaller strings (i.e.gansars) made in Livorno, Tuscany.
For bass strings, some are made at Nuremberg. The best strings of this kind are made at Bologna in Lombardy and from there sent to Venice ... commonly called Venice Catlines.' He then mentions that the best quality strings made in the Summer are sold at the Frankfurt and Leipzig markets.
Note that Bologna, Venice, Nuremberg, Frankfurt and Livorno were all centres of silk production at that time.

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[*] posted on 9-3-2014 at 12:04 PM


Dowland also mentions that some strings were coloured (green, red and blue). The dyeing of silk filament was another trade within the silk industry as mentioned previously. He also cautions about buying strings that show signs of 'hairiness' ('faseling with little hayres'). Hairiness is a characteristic of worn strings made with silk filament.

Lutenist Michelangelo Galilei wrote in 1617 from Munich, Germany to his brother (in Italy?) asking him to obtain 'four thick strings from Florence for his own and his pupil's needs'.
With Florence being a main centre of the silk industry in Italy those 'thick strings' may have been braided silk catlines?
If not, why would Galilei request these strings when he could have obtained the best gut basses that, in the opinion of Adrien LeRoy, London (1574) came from Munich?

Mary Burwell in her lute book (1676) writes that good strings (i.e. treble strings - of sheep's gut or cat's gut) were made at Rome but that the great (bass) strings and their octaves were made in 'Lyons at France'. Yet again a connection with a major centre of the silk industry.

Thomas Mace (1676)
Mace does not mention from what material lute strings are made.
He says there are 3 sorts Minikins (trebles) Venice Catlines for the 4th and 5th courses and most of the other octave strings and Lyons for the basses. He also mentions that 'there is another sort of string(s) called Pistoy Basses that he considered were none other than thick Venice Catlines which are commonly dyed a deep dark red colour. These (Pistoys) are the very best being smooth and well twisted but hard to come by'.
He also mentions several sorts of coloured strings - green, red, blue and yellow.
Mace also tells us that the Venice Catlines were very strong and might be broken only with difficulty by the strength of a man.
He, like Dowland, mentions use of graduated fret diameters (reducing in diameter towards the bridge) to minimise intonation problems with the thicker strings.
So once again there is a connection by association with the silk industries of Venice and Pistoia and the silk dyeing trade.

The final historical step involving silk filament in instrument strings is, of course, the close wound string - copper or silver wire wound around a core of silk filament - an innovation probably too late for the lute but finding general application for the oud, guitar and other instruments up until about 1960 when synthetic nylon filament replaced silk as a core material. Wound strings would have been much cheaper to make than the earlier silk braided strings - with or without spun metal cores - but sounded much different. Although the first evidence of wound strings (open windings?) dates to the late 17th C there is no evidence to suggest that these were generally adopted by the lute community. Perhaps they had just too much sustain and metallic sound for the late 17th/ early 18th C ear to accommodate?
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[*] posted on 9-4-2014 at 06:25 AM


Turning to the early oud strings made from either silk or gut, their physical limitations would have been the same as the strings for lutes.
Apparently nothing is yet known about how the oud sixth and seventh courses were made or from what material - or even how they were tuned (a fourth apart perhaps?)
What we do know from the earliest sources dating from the 10th C (the Ikhwan al-Safa) is contradictory - as discussed on page 8 of this thread. The Bretheren give the number of silk threads required to make each string of a 4 course oud that provide the desired 4/3 diameter increase between each course tuned a fourth apart - Zir 27 threads, Mathna 36, Mathlath 48 and Bamm 64 threads. However, assuming the silk threads are all of equal diameter and the zir string is 0.45 mm in diameter, simply twisting the silk threads into a string does not give the required diameters for the remainder of the strings. The solution previously suggested was:
Zir string - simply twisted, minimal twist - 0.45 mm diameter, tension 35 Newtons.
Mathna string - simply twisted, maximum twist - 0.56mm diameter, tension 31 Newtons.
Mathlath string - simply twisted, maximum twist - 0.69 mm diameter, tension 27 Newtons
Bamm string - four strand roped construction - 0.9mm diameter, tension 25 Newtons.

This being the case the Bretheren were telling us not only how the strings were constructed but the need for diminishing string tension from treble to bass.
The other solution for construction of the Bamm string might have been braided silk. From some preliminary trials in hand braiding thin cord (Japanese Kumihimo) I have found that the diameter increase of the braid compared to the same number of cords simply twisted to maximum twist is about +30% for a fairly loose braid. The percentage increase would be less for a tighter braid. So braiding would give the required diameter increase even without string tension reduction.
Note that braiding must be done in multiples of 4 strands so could also apply to the Mathna and Mathlath strings but not the Zir string that could only be simply twisted (required for maximum strength anyway).

Later the 14th C Kanz al-Tuhaf also gives the number of silk threads for a 5 course oud. All of the thread numbers are divisible by 4 so the strings could all be of braided construction (unlikely though?). The finished strings were rubbed with a glue. Tests have confirmed (reported earlier in this thread) that the glue by this procedure will only consolidate the surface fibres and not completely penetrate a string. This would work as described only for a silk string braided around a core - the glue consolidating just the surface braiding.
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[*] posted on 9-6-2014 at 04:13 AM


The early thick lute bass string(s) necessitated being paired with a thin string tuned an octave higher (octave tuned courses). The thin string provided the upper partial tones missing from the thick string and so brightened the overall sound of the course.
Robert Dowland (1610) mentions that in his time the basses were unison tuned ('the bases must be both of one bignes'). He says that the general custom has been to use octave tuned basses ('to set a small and great string together') but that this practice has been abandoned by musicians as being contrary to the rules of music. So bass string technology, by the beginning of the 17th C, had advanced to the point where an octave tuned bass course was unnecessary. However, the use of octave tuned basses continued to prevail and are mentioned by Thomas Mace in 1676.

Why did the use of octave tuned bass courses continue (possibly until the demise of the 13 course lute in the German Baroque period by the mid 18th C)? Perhaps the sound of the octave tuned basses was preferred to that of unison tuned basses because they (the improved basses) were too loud compared to the other strings? Perhaps those improved strings (braided silk over silver or gold core?) were very expensive so octave tuning continued to be popular as a way to economise on string cost?

We know nothing at present about the construction of the early oud bass courses (6th and 7th) except that there seems to be no tradition of using oud octave tuned basses. So does this imply that the oud basses by the 15th C were already acoustically superior to those made by the European string makers at the time?
The Spanish vihuela - popular in Spain during the 16th C - appears to have been unison strung throughout (up to 7 courses) before falling into disuse by the third quarter. Perhaps those strings - a legacy of the Muslim string making tradition - were no longer being made in Spain following expulsion of the Muslim/Jewish string makers and their expertise to the Ottoman Empire and had to then be imported at great cost? Indeed the vihuela gave way in popularity to the little 4 course guitar (said to be nothing more than a six course vihuela with the 1st and 6th courses removed) that did not require either costly bass strings or costly lute first courses (but did use an octave tuned 4th course).

Were these superior bass strings constructed of braided silk (with or without heavy metal cores) first exported to Europe from the Ottoman Empire (through Venice for distribution to the rest of Europe). Were these superior strings examined by the Italian silk industry who then figured out how to make them? Or did someone, curious to find out if braided silk ganse cords would make good lute basses, carried out a few tests (just as I am now doing) - and so the lute Catline string was born?
Note that the traditional silk braided cords used by the Chinese for making decorative knots were about 0.8 mm and 1.5 mm in diameter braided around a silk core - a good starting point for experimentation without having to go through the trouble of learning silk braided cord making skills.
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[*] posted on 9-9-2014 at 12:03 PM


excellent thread!!

just copied & look fwd to reading later...( rural location again, wifi only on supply run)

thanks again for sharing your work





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[*] posted on 9-10-2014 at 11:42 AM


Glad that the topic is of interest rootsguitar.

I hope to spend some 'hands on' time in exploring the practical possibilities of using silk braided construction for oud and lute middle and bass strings (5th course downwards) - 'Catlines' or 'Pistoys' as the English called them.

As braided cords - made from synthetic filaments such as Nylon on high speed braiding machines - are readily available and inexpensive in the diameters of interest for instrument strings, these will be used to initially explore the possibilities before moving on eventually to hand braided strings of silk filament if the preliminary experiments are reasonably promising.

Braided cord (machine or hand made) may be constructed with:
1) No core (solid).
2) Hollow no core (more elastic).
3) Cored - synthetic or silk filament or metal filament core (for greater specific weight).

Synthetic braided cored strings are available on the market as 'Chinese Knotting Cord' in diameters from 0.4 mm to 3.0 mm - dependant upon quantity purchased (10 yard minimum) - from about 15 cents to 30 cents per yard or metre.
Metal cored braided strings - lead core/nylon or Dacron braid - are available as trolling fishing lines in various diameters (specified also as breaking loads) at reasonable cost (say $10 to $20 per 100 yards).

Initial trials with 'Dacron' braided/lead 7th course string is currently being reported here:

http://www.mikeouds.com/messageboard/viewthread.php?tid=11998

Note that hand made 'historical' gut 'Catlines' of roped construction can each cost up to $50 or so, for the history buffs, an alternative synthetic string with comparable performance - costing only a few cents - might be of interest!
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[*] posted on 9-10-2014 at 11:57 AM


As silk braided cord is not readily available, the ultimate objective here is to hand braid silk filament strings - Japanese style. The apparatus required is simple and easily made - a square or round wooden table - on legs like a stool - with a central hole and the silk strands on weighted spools - the weight of each spool providing the required tension for compactness of the braid.
The braids may range from fairly straightforward to very complex. However for a round braid of small diameter an 8 strand braid might be the economical way to go?
Here is a video of a skilled braider at work making an 8 strand round cord. Not sure how long it would take to make a braided instrument string a metre in length but likely not too long at this speed:

http://www.youtube.com/watch?v=pnCggGQ-z3A

..... and for an unskilled amateur string maker the braided string making process does not have to be completed in one session!
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[*] posted on 9-17-2014 at 11:27 AM


"The Silk Industry of Renaissance Venice" by Luca Molà - mentioned earlier in this thread as relevant to this topic - is now available from John Hopkins University Press, a $64 book on sale for $18 plus shipping. I have just received my copy - cloth bound, 480 pages - a very nice edition to read in armchair comfort.
Very good reviews so essential reading for those interested in the early development of the silk industry.

https://jhupbooks.press.jhu.edu/content/silk-industry-renaissance-ve...
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[*] posted on 9-20-2014 at 04:43 AM


Preliminary trials with varnished lead cored/Dacron braided fishing line have been promising when tested on a 7 course lute - so may indicate the viability of this form of construction for lute bass courses of the late 16th C - Catlines and Pistoys.

This type of 'ready made' low cost trolling line of braided construction is made by a number of companies in various diameters and sized according to breaking load. Standard breaking load range is 12 pound (5.5Kg), 15 pound, 18 pound, 27 pound, 36 pound, 45 pound, and 63 pound with approximate outside diameters of 0.66 mm, 0.69 mm, 0.74 mm, 0.86 mm, 0.94 mm, 0.99 mm and 1.07 mm respectively. So there is ample scope for using these modern cords for testing as instrument strings at low cost.

If solid metal cored strings of braided silk construction were used historically it is unlikely that pure lead would have been used (it is not strong enough to be drawn into fine wire) but pure gold, pure silver and perhaps copper may have been the alternatives as the drawing of these metals through dies into fine wires is ancient technology dating back thousands of years.
With the exception of copper, pure gold, silver and lead remain in a soft malleable condition when worked (by hammering or drawing into wires) - i.e. they do not work or strain harden like many other metal alloys. Work hardened copper, however, may be easily returned to a softened state by annealing - by heating to red hot and then quenching in water.

Lead is particularly interesting as a potential core material as it is low cost, denser than silver or copper but also will slowly stretch (creep) under low loads at room temperature. So as a core in a braided line under load it will stretch until only the braid is carrying most of the tension. Lead being so soft has a low tensile strength so could not be used alone as an instrument string. The same applies to pure gold and silver both with low tensile strength.

A downside of lead as a metal is that it is toxic if ingested as dust or particularly as soluble salts of lead (although endemic in the environment of modern society) - so should be handled with respect (wear plastic gloves when handling and dispose of properly as a hazardous material).

As the test strings in these trials are varnished and string use as a 7th course infrequent, abrasion wear of the braided jacket is low so that the lead core is essentially safely sealed inside the string. Also the lute 7th course is usually played open and rarely stopped on the fingerboard.

For the experimenter, braided lines have a further practical use as it is a simple matter to remove the lead core to leave the hollow braided sleeve. The lead core may then be replaced with alternative cores of solid wire gold, silver or copper. With 22 gauge gold wire (0.64 mm diameter) costing today from about $100 to $200 a foot length (30 cm) pure gold wire as a core material will not be used in these trials. Pure silver (0.999 purity) costing about $3/ft for 22 gauge wire is a possibility but can wait until trials with lead and copper cores yield positive results.
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[*] posted on 9-21-2014 at 04:23 PM


It is a simple process to create modern 'Catline/Pistoy' bass strings from braided Dacron/lead cored fishing lines. For this trial a 27 pound breaking load line - costing less than 10 cents a metre - is being used.

A length of line was first tensioned with a 3 Kg load and then wiped with two coats of a thin varnish - in this case TruOil. The varnish penetrates the braided sleeve and consolidates it with the core - as well as providing additional surface abrasion resistance and sealing of the lead core.
In retrospect the varnish should be thinned further (50/50?) to ensure a uniform coating - perhaps with more coats.

On the string test rig , for a string length of 60 cm and diameter of 0.77 mm the following results were obtained :
Pitch standard A440
F (87 Hz) - tension 2.94 Kg.
E (82 Hz) - tension 2.59 Kg
D# (78 Hz) - tension 2.33 Kg
D (73 Hz) - tension 2.08 Kg
C# (69 Hz) - tension 1.85 Kg
C (65 Hz) - tension 1.65 Hz

String sustain (judged by my aged ear) ranged from about 12 seconds+ at the highest tension to about 8 seconds at the lowest tension.

Mounted as a unison pair 7th course on an F tuned lute - tuned two semitones (78 Hz) below the sixth course - the strings took a while to stabilise in pitch but are now performing quite well in my opinion. So far no wear of the braided Dacron sleeve is in evidence.
Attached, for information, are a couple of audio clips of the unison pair sounded alone and as part of a 16th C dance composition for lute - played with soft fingertips.

Next to run some trials using copper as an alternative to the lead core.

[file]32613[/file]

[file]32614[/file] [file]32615[/file] [file]32617[/file] [file]32621[/file]

[file]32623[/file]
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[*] posted on 9-22-2014 at 01:27 PM





Interested in the varnishing process you've been using, do you coat a large length of material then let it dry and cut it into string lengths?



Just got a hold of some waxed linen kite twine ( also some of dacron ) and thought to try your binding idea to make strings for my 8c.

Also someone gave me some nylon harp strings to try as well.

Curious if you think established harp string construction informed lute/oud set ups in the far past.


---Thanks

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[*] posted on 9-22-2014 at 04:07 PM


I am just varnishing each string length (say about 100 cm). The varnish is thin enough to soak through the braided sleeve to bind it with the core. The second varnish coat then fills in any surface hollows to produce a smooth, uniform string. During this process, the string length is placed under tension so that some equilibrium between braid and core is achieved prior to varnish application.

Note that twine (twisted fibre construction) is not the same as braid so a varnish may not fully penetrate as a binder (if that is the intention). Also varnish will not stick to wax.

Modern monofilament nylon harp strings are no different to modern monofilament nylon lute strings as far as I know.

Harp strings are somewhat less critical than lute strings in that all harp strings are played 'open' whereas the first six courses of a lute must be uniform enough to remain 'in tune' with each other when stopped on the fingerboard.

I know nothing about harp gut string construction in the dim and distant past but imagine that the gut string makers supplied strings to both lute and harp players on demand (as they did for many other, non musical, applications of gut strings).
Some instruments like the old Irish harps were strung with metal (brass or silver) strings and played with long fingernails as plectra - the precise drawing of small diameter metal wires being ancient technology. The bass strings of those instruments were made by twisting two wires together to provide the required flexibility necessary for best acoustic performance - equivalent to bass strings of twisted filament construction.
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[*] posted on 9-25-2014 at 03:35 PM


As the lead core is not tightly bound to the Dacron braided sleeve it is a simple matter to remove the lead core and substitute a core of another material for testing - be it copper, silver or gold.
To remove the lead core just rub the last couple of centimetres of end of the line with a smooth hard rod (e.g. a metal rod like a screwdriver) to compress and squeeze out a bit of the lead core. Grip the end of the core with pliers and hold the end of the sleeve (wearing plastic gloves) and just pull to remove the core. Place the lead core in a sealed plastic bag for safe disposal as toxic waste.

For this next trial a pure copper core will replace the lead core. The most convenient and economical way to obtain small quantities of small diameter copper wire is from domestic appliance flexible electrical cords - just strip the plastic insulation covering from the copper conductors with wire strippers. In this example I am using wire stripped from some scrap telephone wire - the conductors measuring 0.64 mm diameter (22 AWG).
As the copper wire is in a semi hardened 'springy' state it must first be annealed to make it soft. To do this the wire is made into a small diameter coil and heated with a small propane torch until red hot and then dropped into a pan of cold water to quench it.

Working with a metre length for convenience, the end of the soft, stripped wire is first made smooth with fine sand paper and then pushed into the braided sleeve. The sleeve is then pushed little by little on to the core - the sleeve opening up in diameter as it is pushed over the wire - until the core is completely covered by the sleeve (it takes a bit of patience to complete!).
The covered string is then suspended under a load of about 3 Kg and wiped with two coats of TruOil varnish to bind and seal the Dacron sleeve to the copper core.

Next to test the copper cored string on my test rig.

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[*] posted on 9-26-2014 at 11:41 AM


The varnished copper cored string measures 0.89 mm in diameter with the solid core measuring 0.64 mm. Even after annealing the copper core the finished string feels too stiff and lacking in flexibility.

These are the results of the string test for information:
F (87 Hz) - tension 3.5 Kg
E (82 Hz) - tension 3.1 Kg
D# (78 Hz) - tension 2.8 Kg
D (73 Hz) - tension 2.4 Kg
C# (69 Hz) - tension 2.2 Kg
C (65 Hz) - tension 1.9 Kg

The stiffness of the string made it very sensitive to tune on the lute (D#) so the trial was terminated. It is possible that a multi strand copper core (salvaged from electrical appliance flexible power cords) might give better results so this alternative will be tested later.

Note that although the density of copper is 8.96 gm/cc the equivalent density (according to the Mersenne-Taylor law) of the braided composite string is only 5.0 gm/cc the Dacron sleeve being about 1.4 gm/cc. Likewise for the lead cored string the equivalent density is only about 5.7 gm/cc compared to the density of lead at 11.4 gm/cc.

I have just received some samples of braided Chinese knotting cord so will report on these next.
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[*] posted on 9-30-2014 at 11:54 AM


The company 'Tangles n Knots' stock a range of Chinese braided knotting cords and kindly sent me a free sample card of their products in the following (approximate) diameters - 0.4 mm, 0.5 mm, 0.8 mm, 1.0 mm, 1.4 mm, 1.5 mm, 2 mm, 2.5 mm 3.0 mm. The cords are braided in nylon filament around a simply twisted nylon core and come in a wide range of colours. The cords are sold in 10 yard lengths for just over 30 cents a yard or in longer lengths for lower cost per yard.

The cords are very flexible and the braided sleeve appears to be of relatively loose weave (?) - the attached image is the 2 mm diameter braided cord. The cores are easily removed so could be replaced with cores of other materials. Some kind of core would seem to be necessary to ensure uniform roundness of the string under tension. Twisted silk filament might be a better core material than nylon and would ensure binding of the nylon sleeve to the core when the string is varnished
One interesting alternative core possibility might be worn wound strings (smaller gauge Pyramid lute strings perhaps?) - to give them a new lease of life as a heavier gauge bass string.

So, will order some 10 yard lengths for experimentation and see how it goes.
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[*] posted on 10-12-2014 at 12:01 PM


The tests with braided Dacron/lead core trolling line previously reported were for Sunset brand Tel-a-Depth line of 27 pound breaking strength (12 Kg) - lead core diameter (unloaded) is 0.53 mm. Line diameter loaded 0.75 mm.

Continuing to investigate the potential of braided lead core fishing line a 100 yard spool of 63 pound (29 Kg breaking strength) Sunset brand Tel-a-Depth nylon braided lead cored trolling line was purchased on EBay for $18 (including shipping). This is half price because the line colours are not perfect - a cosmetic fault that does not affect the physical properties.
To prepare the line a metre length was loaded with 4.4 Kg and then wiped with two coats of TruOil varnish.
Diameter under load is 0.94 mm and core diameter unloaded is 0.45 mm.

Surprisingly the lead core of this larger diameter 63# line is less than that of the 27# line - I was expecting the core diameter to increase with line diameter but perhaps it is a case that more 'weight' is required for the smaller diameter fishing lines to sink through the water when being trolled?. The braid is somewhat coarser because it is the braided sleeve that carries the load not the soft lead core that will stretch under load so that it carries little if any of the string loading. This means that the larger diameter 63# line will have a relatively lower linear density than that of the 27# line so will not perform as well at the lower pitch bass frequencies as the 27# line as we may see on the string test rig trials. This may be a good thing for bass string performance - the smaller diameter - all else being equal - the better.

The attached image shows the varnished (2 coats) 27# test line (red colour) alongside the varnished (2 coats) 63# line (blue colour) for comparison. It can be seen that 2 coats of varnish is insufficient to completely seal the braided sleeve so more coats will be applied until a smooth surface is achieved before testing.

A 100 yard spool of 12 pound (5 Kg breaking load) of another brand of braided/lead core line by Sufix is on order from EBay suppliers for future testing. No doubt different manufactures will have differing sleeve breaking strength to core diameters in the design of their lines. The range 12 pound to 63 pound lines seems to be the manufactured 'standard' range commercially available.


[file]32790[/file]
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[*] posted on 10-15-2014 at 11:45 AM


The preliminary testing of the larger diameter (blue) lead cored line has been completed with consistent results.
The string was given another coat of TruOil varnish (total 3 coats) that has produced the required smooth surface finish. String diameter after varnishing and under load is 0.94 mm. Test string length is 600 mm and string tension range limited to between about 2 Kg to 3 Kg - the approximate range for a workable bass string.

Here are the results obtained on the string test rig - pitches at A440 standard, string tension in Kilograms force.
G 98 Hz - 3.2 kg - Sustain about 8 seconds
F# 93 Hz - 2.9 Kg
F 87 Hz - 2.6 kg
E 82 Hz - 2.3 Kg
D# 78 Hz - 2.0 Kg - sustain about 7 seconds, temporary pitch increase when plucked
D 73 Hz - 1.8 Kg - ditto

The approximate density of the compound string is 3295 Kg/m³ compared to the previous (red) string density of about 5650 Kg/m³. So - not surprisingly - this larger diameter string being of lighter composite density (more nylon filament to lead core ratio) cannot perform as well as the red string at lower bass frequencies.

The 63# test string is a manufacturer's second quality product said to be due to cosmetic colour deviations but I have to wonder if a wrong lead core diameter was also a reason for the downgrade to second quality?

Awaiting delivery of the 12# line for testing.
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[*] posted on 10-18-2014 at 11:50 AM


This link may be of interest mainly because of the string coating process( The specifics of powdered glass added to string for kite fighting is of course irrelevant).

It includes:

Charkho = Using a spinning wheel to coat kite string.


Entangled: A Documentary Film by Aditi Desai & Kai Fang

http://entangledmovie.wordpress.com/author/aditivdesai/



The lower photo is titled: coating the string (manja) by hand



[file]32950[/file]

[file]32952[/file]
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[*] posted on 10-18-2014 at 12:18 PM


Kite string coating in India:
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[*] posted on 10-18-2014 at 12:47 PM


Twenty years ago, they sold in Paris oud string sets with the trebles in natural gut (the highest three strings, i.e. 0.61, 0,79 and 1,04 mm) combined with the three lowest strings wound around a red natural silk core. The brand was "Triomphe, Cordes pour Aoud". These sets were balanced and delicious sounding on a good oud. They were the ORIGINAL string set for ouds, for centuries...
I wander if we couldn't get a string maker somewhere to make them again, since oud playing is now very popular all over the world, with a great potential market for these sets which would be unique in the business?
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[*] posted on 10-19-2014 at 04:08 AM


This recent topic by Yaron Naor about the restoration of an old oud owned by Yair Dalal includes information on the inspection of string fragments found on the instrument.

http://www.mikeouds.com/messageboard/viewthread.php?tid=13030

The strings were gut trebles and wound/silk core basses - the silk filaments being dyed a red colour. Perhaps from the same French manufacturer? Interesting that string sets of this kind were still available 20 years ago (1994) as I imagine that they quickly went out of fashion when modern nylon monofilament and wound nylon filament core strings became generally available at much lower cost after the 1960's.
I purchased gut and wound silk filament oud strings in Cairo in the early 1960's and they too were of French manufacture as I recall.
Is there any more detailed information about the French manufacturers of this type of string? That would be useful historical data.
No doubt there are string makers who might be persuaded make custom sets of this kind of string - for a price - but I doubt if there would be any great demand among modern oud players.

[file]32962[/file]
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[*] posted on 10-24-2014 at 11:12 AM


The 12 lb (5.4 Kg) breaking strength braided lead core fishing line has arrived for testing. Cost including shipping - $20 Can. for 100 yards (91 metres). Made in Taiwan - China and Taiwan appear to have the expertise and high speed braiding machines to make these small diameter braided cords at low cost.
Line outside diameter unloaded is 0.55 mm and lead core diameter 0.40 mm. Brand is 'Sufix'.

A length of line has been prepared for testing with 2 coats of TruOil varnish with the string loaded with 2.4 Kg. Diameter under tension is 0.52 mm.

Test results next.

(After the attached image was taken, my Canon PowerShot A470 camera partially failed so it has not been possible to provide a macro image of the line. The problem may be due to a failed ribbon cable that controls the lens shutter so may be too costly for a Canon repair. Ribbon cables are available on E Bay from China for about $4 so I may try to repair the camera myself. Pity as this has been a useful camera for macro photography over the past few years).

[file]33007[/file]
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