| Apart from differentiating between
"grené" and "granulado" the imprint of the rhombos - "holes" in
between the threads - can be more or less visible at the wire side of
the papel. Pettigiani takes it for granted that the wire side gets the
gum and the felt side gets the print. This not true and certainly not
when dealing with the national papers of the 1953-1959 period.
The paper mesh as we see it comes from a weave that has vertical lines/threads and horizontal threads of various densities; the usual density is 28-30 vertical threads(warp) per horizontal centimeter AND some 20 horizontal threads (weft) per vertical centimeter! The gauges noted as follows - 28/20, 30/20, 24/20, etc... Not only density is important, the weave binding is a cardinal aspect. It had been a so-called linen-binding for all mechanically manufactured papers till 1938; after 1938 we could meet a so-calle twill binding. Pettigiani seems to repeat what Merlo wrote in 1966 assigning the "papel rayados" to the linen-binding having a density of say 20/30 instead of 30/20! When having a better look at the picture of the "Tela metalica de papeles rayados" you will see that it is a twill! The various "trrama' are assigned letters: V grené W granulado vertical X tela Y rayado vertical Z rayado horizontal We have here both the types of weave binding and orientation of the line of AЯ combined.... |
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Juampiweb 28 Sep 2010 15:12 Hola Rein te felicito por el análisis que hacés sobre el tema porque siempre es bueno desde un punto de vista imparcial poder analizar socumentos y libros que enriquecen a toda la comunidad; en especial por el gran conocimiento que tenés sobre el tema y que desinteresadamente compartís con todos nosotros. Hasta ahora seguimos sabiendo que no hay ninguna obra completa que pueda encarar el tema en su totalidad primero por ser muy extenso y otro por los diversos puntos de vistas. Los filatelistas que tratamos de hacer una colección mas o menos seria sabremos que es necesario consultar de todas las fuentes posibles para lograr una colección pulida en casi todos los detalles. Nuevamente agradezco tu gran aporte. Saludos.
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| Pettigiani having 5 types of "trama" V, W,
X, Y and Z mixing categories of binding with a particular shape of the
watermark is a methodological mistake.
In the period concerned 1935-1960 only two categories of binding - two major weaving techniques existed that would be found reflected in the paper wire (mesh) that forms the background of our watermarks! The warp is the vertical thread in the loom, the weft is the filling yarn that will be fed through the warp threads from left to right, right to left, etc.
From the very beginning of the machine-made paper "plain weave" or linen-binding had been used. This continued into the 1970-ies, but most of the paper manufacturers had been changing to the more flexible twill weave and certainly with the availability of plastic fibres twill weave became dominant and later on even more complex weaving patterns were introduced. The twill weave we will find only from 1938 onwards. In Argentinean postage stamps this is to be found in what is called "papel rayado" since 1944 [or maybe bit earlier?]. The twill weave is a-symmetrical hence my use of the term "a-symmetrical paper wire". Plain weave is symmetrical and as the vertical threads are usually more dense [30/cm horizontally] than the horizontal threads [20/cm vertically] we see a stretched rhomboid in the vertical direction. This the so-called "granulado"!!! When the vertical threads are not so densely planted, let's say 24/cm horizontally or a bit less, we get to see what was called here "Tela" "Plain weave is the simplest type of weave. A single weft is progressively passed over one warp and under the next warp, working across the width of the loom. The weft is then passed back through warps in the opposite direction alternating from the previous over-and-under pattern. Variations are possible by using double or tripled warp or weft threads in a variety of combinations." "Warp-faced weave fabric has greater number of warp threads per centimeter, while weft-faced weave fabric has a greater number of weft threads per centimeter. When both the warp and weft threads are equal in number per centimeter, it is termed balanced weave. All textiles fall into one of these categories." The quoted texts are from the Brigham Young University website with the screen-copies I made added to the text. Similar texts and sites can be found by Googling "twill weave".....
"granulado":
"Twill weave is similar to plain weave in that the weft passes over and under warp threads. However, warp yarns are skipped at predetermined intervals to create a diagonal rib in the weave."
"rayado":
The twill being asymmetrical is more prone to torsion than the plain weave and this results in the visual effect of slghtly ascending or descending lines - red in the scheme - that helps givng the impression of "rayado". |
| ... Pettigiani uses a scheme of the twill
for the "papeles rayados" which is correct, but he doesn't explain it
any further.
What should have been done is to insert the notion of "eje de enrollamiento" [direction of paper] - which is discussed a bit later - and leave the description and the orientation of the watermark where it belongs. I will keep on telling it - you can not study the types of paper and watermarks - not just of Argentina - without dealing with the "direction of paper " first! Trama X [Tela] is just a form of plain weave with - as mentioned above - a density that differs a lot from the usual 30/20! Another clearly different one is the 30/16 plain weave used in 1943 for the USA coated paper. Pettigiani can not decide which type of trama to go with it! |
| .... An additional info that should be more
or less to the same extent as what I had before! http://www.sweco.com/es/wire_glossary.html
Tipos de telas metálicas "El ligamento tafetán es el ligamento usado con mayor frecuencia. Cada alambre de la trama pasa alternativamente por encima y por debajo del alambre de la urdimbre y viceversa Los diámetros de la urdimbre y la trama son normalmente iguales. Se dispoen de mallas de ligamento tafetán con aberturas de 10,7 mm (2 mallas) a 0,05 mm (325 mallas). El ligamento sarga es más fuerte que el ligamento tafetán. Cada alambre de la trama se cruza alternativamente por encima de dos alambres y después por debajo de otros dos alambres de la urdimbre. El ligamento sarga se usa normalmente para instalar un alambre de diámetro más grueso que el normal en relación con una malla dada." The twill weave shown here is 2/2 instead of 2/1 or 1/2 = 2 up and 2 down instead of 2 up and 1 down etc.... The Argentine "rayado" is 2/1 !!! The Argentine "granulado" is 1/1 !!! |
... Discussing the watermark itself
Pettigiani starts off with the picture of the dandy-roll or bailarin:
 The subsequently described watermarks needed to be related to
the dandy-roll both in the sense of orientation:
- parallel watermarks with the line of RA runs across the axis of the dandy-roll or - orthogonal watermarks with the line of RA runs parallel to the axis of the dandy-roll; and in the visible orientation or readability of the letters on the dandy-roll: - AЯ as in the picture or - RA Also Pettigiani should have explained a bit more about the wire side and the felt side of the paper. He just assumes that the wire side gets the gumming by default and the felt side the print. This is not the case in quite a lot of Argentine stamps - not of the P&R I period nor before nor after! starting point for even further studies... |
