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jdowning - 4-24-2015 at 11:58 AM
The braided lead cored strings that have been under test on my 7 course lute were examined for abrasion wear today under magnification. I play this
lute mostly daily for about an hour each day. The strings are struck with soft fingertips.
The 7th course unison pair on close examination show no signs of abrasion wear after 8 months.
The Sufix #12 string on the 5th course, diameter 0.52 mm has a bright sound similar to an equivalent Pyramid wound string. The density of this
compound string is about 6450 kg/m³ with the density of the nylon braided sleeve being estimated at about 1010 kg/m³.
This string has been under test for 4 months. Although no deterioration in acoustic performance is obvious there has been noticeable string abrasion
wear at the plucking location between sound hole and bridge and, to a lesser extent, over the fingerboard.
The attached macro image shows the most extreme example of wear localised over a short length at the plucking location. Although it looks terrible
remember that the string diameter is 0.52 mm so the abraded nylon filaments are very fine (and of relatively very low mass) and therefore have an
insignificant effect on string vibration.
It may be possible to improve abrasion resistance with a heavier varnish coat or harder varnish.
This will also be an opportunity to investigate if the 'hairiness' might be removed or corrected. In the days (19th C) when silk violin strings were
available, this 'hairiness' caused by the abrasion of rosined bow hair against string was removed by very quickly running the string through the clean
flame of an alcohol lamp. This might be a solution but tests so far indicate that success may require some practice to burn off the hairs without
damaging the string varnish binder. So let's give it a try!
[file]35040[/file]
jdowning - 4-26-2015 at 11:33 AM
Burning off the fine hairs on a string using an open flame is a tricky operation when working with nylon polymer. Less so with silk strings as silk
filament burns to a brittle carbon mass that is easily brushed away whereas nylon filament under the same conditions will melt into a ball and lose
strength.
The burn test is a sure way to identify silk filament from polymer filament - it also smells like burnt hair.
Nylon polymer will melt at a temperature of around 250°C but the temperature of the flame of an alcohol lamp might reach well in excess of 1100 °C.
The string must therefore be moved sideways through the flame very quickly - as fast as possible - so that only the hairs are affected by the heat and
not the braided sleeve. When correctly done the hairs just melt into tiny spheres - incorrectly done (too slowly through the flame or more than one
successive pass) and the braided sleeve will be damaged as seen in the attached images. As the tensile strength of the string is in the sleeve and not
the lead core, the damage shown in this example - where the sleeve has been partially burnt through to the lead core - means that the string is of no
further use.
Is it worth trying to recover worn braided strings this way? Probably not as even after 4 months use with some abrasion wear in evidence but with the
sleeve still relatively intact the string in this test still sounded OK. Had the string continued in use until the sleeve became worn through it would
have broken at that point.
Replacement cost for a new string? About 20 cents plus a few minutes of my time!
rootsguitar - 10-10-2015 at 05:14 PM
wanted to add this link:
https://youtu.be/2uFVV214HY8
In the first two minutes it shares the relevant info...have another scan to add about domesticated silk worms very soon.
The tradition of harvesting silk & mulberry leaves on a small scale in rural China is related in the article.
Will it post here soon...this is a good thread to review for my interests & am glad to try encourage its continuation!
jdowning - 10-12-2015 at 12:01 PM
The mulberry silk worm (Bombyx Mori) - domesticated by the Chinese for millennia (since 2700 BC?) - cannot survive without human intervention (like
Indian corn) - although, of course, it must have once been a wild species. Other species of silk moths (that do not feed on the mulberry plant and so
are forest dwellers), are classified as 'wild' silk producers and India has a long history of wild silk production as a 'cottage industry'.
As far as I know, from historical record, the silk used for making silk filament instrument strings (such as for the ancient Chinese Qin or the oud)
has always been, for convenience, Bombyx Mori silk although no doubt wild silk might also be used? (never tried it myself)
Anyone thinking of home production of silk filament or is seeking information about both domesticated and wild species of silk moth should check out
this site. Lots of 'how to do it' practical advice, detailed images, and references:
http://www.wormspit.com/
Seriiculture or silk farming is an interesting but time and resource consuming project for the amateur. I prefer to purchase silk fibre for string
making 'ready made' from commercial suppliers (like Treenway Silks).
rootsguitar - 10-12-2015 at 01:23 PM
That's a great link...lots of good photos.
Here's an excerpt from
Mulberry Trees and Silkworms
Sericulture in Early Virginia by Charles E Hatch Jr
" There is little reason to wonder why the early colonists at Jamestown were conscious of silk, the silkworm, and the mulberry tree, for their
sovereign James l was a devout patron of sericulture. In it he had a lasting and persistent interest. He encouraged his subjects in this too requiring
land owners to purchase and plant mulberry trees and recommending they foster the cultivation of silkworms as both a desirable and a necessary
endeavor. 
All over England this was emphasized, and it led to the establishment of mulberry nurseries as well as to the construction of silkworm accommodations.
The King himself took the lead in planting a tract in mulberries near his Westminster palace and later building a special establishment with a keeper
employed to care for his worms all the while urging his subjects to follow his example..."
( continues...)
Mulberry Trees and Silkworms: Sericulture in Early Virginia
Charles E. Hatch, Jr.
The Virginia Magazine of History and Biography
Vol. 65, No. 1 (Jan., 1957), pp. 3-61
Published by: Virginia Historical Society
Stable URL: http://www.jstor.org/stable/4246279
Page Count: 67
An arguable case for Silk strung lutes at Westminster Palace?
Great data & references in this thread, Jules Verne even comes up!
[file]37143[/file]
jdowning - 10-13-2015 at 05:05 AM
Sericulture in the American colonies was essentially a pioneering failure as it was in England for a variety of reasons - and was never of any
industrial significance. There was however a thriving silk weaving industry centred in London thanks to the immigration of skilled weavers fleeing
persecution in Europe in 1685. Most of the silk filament used by the weavers was imported from the Europe and the East.
As mentioned on page 11 of this thread(!) the weavers also made braided silk trimmings (cords) for clothing that I speculate might have been pressed
into service for instrument strings (hence my current ongoing investigation into braided/lead cored lute bass strings). So it is possible, I suppose,
that this kind of instrument string was made by the weavers of London but more likely such strings (if they did exist) were imported from the
established silk industries of Europe in Italy and France - strings with names like 'Lyons' and 'Pistoy' basses.
For information, here is another article that I wrote on the subject a year ago published in FoMRHI.
http://www.fomrhi.org/vanilla/fomrhi/uploads/bulletins/Fomrhi-128/C...
jdowning - 10-13-2015 at 09:23 AM
The low G1 tuned Pyramid wound string on my Colascione project is to be replaced with one of my braided lead cored strings reported on the previous
page of this thread. The most suitable candidate is the 63# 2 strand twisted core string prototype that I have to hand and will do for preliminary
testing.
My string test rig currently has a 76 cm maximum string length capacity with the Colascione string length being 79 cm. The rig will therefore be
modified later to accommodate a longer string length by installing a second bridge behind the existing bridge.
The tension trials for the 64# 2 strand core prototype were carried out with a 60cm string length. The string is of composite construction, outside
diameter 1.2 mm under tension. However, from the test results and using the handy free StringCalc32 software, by trial and error, the equivalent
string density for a plain string has been determined to be about 3750 Kg/m³ (or 3.75 gm/cc).
Using this density in StringCalc32 ('User Def 1') the string tension for the string at 79 cm vibrating string length is determined by adjusting
'Tension for Calculation' until the string diameter becomes 1.2 mm. (See attached image).
So for String Pitch G1 (G') at A440 standard of frequency 49Hz the string tension is 25 Newtons (about 2.5Kg) which should be about right. We will
see.
[file]37145[/file]
jdowning - 10-14-2015 at 03:34 PM
In the meantime - with reference to historical record about silk instrument strings.
Although the historical record is clear (although limited) about silk strings and details of their manufacture being applied to instruments such as
the ancient Chinese qin and the Oud, the only direct reference to silk instrument strings in the European culture that I am aware of at present is
provided by Athanasius Kircher in his 'Musurgia Universalis' published in Rome, 1650. This brief reference - image attached - is in Book 6, Chapter 3
dealing with string technology, materials and manufacture etc. is entitled De Chordis Sericeis (about silk strings).
I remember very little of Latin learned during my school days (when basic knowledge of Classical Latin and Greek were still an entrance requirement to
universities like Oxford regardless of discipline - no longer it would seem).
Attempts to translate this passage by Kircher using free on-line Latin-English translation services just results in useless, incomprehensible garbage.
I suspect from a quick, unscholarly, uninformed review of the text that Kircher is not telling us very much about what we already know - such as silk
is produced from the intestines of the Bombyx caterpillar (?) - but there may be a small pearl of information tucked away in there as well?
Are there any Latin scholars among the Forum members who can provide a translation?
[file]37149[/file]
jdowning - 10-15-2015 at 03:05 AM
Note that although Kircher mentions silk strings he also states that the strings of lutes and theorbos (extended neck double pegbox lutes) were made
from animal intestines.
Attached is an extract from FoMRHI Comm. 1937, page 3. The full article on gut instrument strings is freely available on-line - Google search.
rootsguitar - 10-15-2015 at 05:17 AM
A most welcome reference made all the more interesting that it may be translated here at some point!!
Being unfamiliar with the Author of that posted portion of Musurgia Universalis, I began to read about him in:
Athanasius Kircher, Musurgia Universalis (Rome,
1650) : the section on musical instruments
Frederick Baron Crane
University of Iowa
1956
here are a few excerpts :
“ He ( Athanasius Kircher) is credited with a number of
inventions; those of importance include the magic lantern,
the Aeolian harp, and one of the earliest counting-machines…”
“…. it is not surprising that his works, without
exception, were written in Latin. On the other hand, the
vernacular was used almost exclusively by his time for
musical treatises; his is perhaps the last major one
published in Latin. His style is based on classical Latin,
but with frequent concessions to modern constructions. “
another by Kircher:
“Here at Rome they make the heaviest
lute string of nine intestines, the next of eight, and so on
to the last and smallest, which consists of one intestine.
But if some artisan wished to proceed more subtly in this
business, he could extract the proportions of the diameter of
one to the next from the table of harpsichord strings that we
presented above, Column V. But these matters should be…”
an interested reader can follow this link to Frederick Crane’s complete paper :
http://ir.uiowa.edu/cgi/viewcontent.cgi?article=5071&context=et...
The paper also mentions another work by Kircher that may be of interest to this forum:
Oedipus aegyptiacus
In a work on Aegyptian hieroglyphics, Oedious
aegyptiacus (3 vols., Rome, Vitale Mascardi, 1652-1655),
Kircher discusses Egyptian music and the musical knowledge
revealed in the hieroglyphics (Vol. Ill, Parts I and II).
jdowning - 10-15-2015 at 07:52 AM
I have found the F.G Crane translation to be of value in my current research into the Colascione and origins of the Tiorba. Unfortunately the
translation does not include PART 1 on string materials etc. and so the bit on silk strings is missing.
Be careful in referencing Kircher's work on Egyptian Hieroglyphics as it is now generally discounted as being largely fantastical!
rootsguitar - 10-20-2015 at 10:40 PM
the career point of Kircher as he wrote it is described in:
Egyptian oedipus
D. Stolzenberg (2013)
R. Descartes (“ cogito ergo sum “ ) also is compared to Kircher there.
It seems it was regarded fantastical by some even then!
Also here’s an added sericulture bit ( related to the TAR lute thread,whose double-bowl shape is carved from mulberry wood).
" The black mulberry (M. nigra)... is a native of western Asia that spread westward in cultivation at an early period. Up to the 15th century it was
extensively grown in Italy for raising silkworms..."
http://www.britannica.com/plant/mulberry-plant
& in the UK:
" The black mulberry was imported into Britain in the 17th century in the hope that it would be useful in the cultivation of silkworms (Bombyx
mori)…
https://en.wikipedia.org/wiki/Morus_nigra
Not a big impact on the braided silk investigations but I thought it was interesting that these trees had spread to Europe before the TAR's modern
form developed.
jdowning - 10-23-2015 at 11:47 AM
The second replacement string for the drone bass - tuned G1 - for the Colascione project on this forum, will be made with a 2 strand twisted lead core
(2X 0.5mm diameter) and the braided sleeve from a 27# line. The latter is a smoother braid than the 63# braided sleeve used on the first prototype
drone string currently under test on the Colascione. Hopefully this will reduce string noise due to left hand fingers sliding along the string over
the fingerboard while stopping the string.
In order to produce a tighter twist in the 2 strand core, the lead wire will be lubricated with paint thinner prior to twisting. The paint thinner
will be compatible with the varnish binder. The assembled string will then be saturated with polymerised Tung oil as a binder for the braided
sleeve.
Not sure how well it might work but no harm in trying with a total material cost of only about 20 cents a string.
rootsguitar - 10-25-2015 at 04:23 AM
one more addition!
Here's a rabab player (whose instrument is made from mulberry wood). The tassels that are tied to the pegbox are so similar to your premise on
improvised strings that it seemed a worthy addition here. Some of the strings even seem to be made from them?
http://www.dailymotion.com/video/x2mj93o
Good adventures seeing how all this ties together...
jdowning - 10-25-2015 at 06:57 AM
Impossible to tell from the video.
Note that I am not suggesting that lute strings of silk braided construction were improvised in any way but were being manufactured specifically as
instrument strings by silk spinners skilled in the specialised task of making passementerie cords (or ganse) loaded with gold or silver ribbon.
Naturally these strings would have been made where the major European silk industries were concentrated e.g Lyon (France), Pistoy (Pistoia Italy),
Munich (Germany), Catline (Catalonia Spain) etc - lute strings that carried the names of these manufacturing centres. See page 11 of this thread for
details (for some reason I cannot now copy and paste a link to the page).
OK- now it works, problem with mouse.
http://www.mikeouds.com/messageboard/viewthread.php?tid=10010&p...
rootsguitar - 10-25-2015 at 11:07 AM
Was good to review your thread's goals there on page 11, best to keep streamlined to stay coherent
...sure enjoyed the past week with a lot of internet access & time to follow up on the subject of lutes, strings & the renaissance era.
Keep on posting it sends a good ripple out there & look fwd to checking this forum near the New Year.
jdowning - 11-6-2015 at 04:29 PM
My string test rig has now been modified to accommodate string lengths up to 85 cm in order to test the 79 cm strings required for the Colascione
project.
As there was sufficient length of material on the pulley support frame, the pulley was moved lower on the rig by about 12 cm. An extension piece was
then simply spliced, fitted and glued to the rig as shown in the attached image to give the sliding nut at the lower end of the rig that extra scope
for string length adjustment.
The test rig in its original form can be seen on page 5 of this thread.
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