confieso que estoy un poco perdido con tanta Klawun, Dietzgen... ¿nos puedes explicar un poco la relacción de estas marcas con Faber?
¿cuando aparecieron , donde y porqué?
Facil, solo tienes que buscar en el mundialmente reconocido foro de reglas que creo que se llama ARC

:
http://arc.reglasdecalculo.org/index.php/topic,403.0.html Estoy recopilando algo de información sobre Klawun, aquí hay algunos apuntes que he copiado de diversas fuentes:
Feinmessinstitut Klawun (Institute for Fine Measurement) was a distributor
of SRs from several manufacturers. At times they ordered models to their own
specs.
"Alles was Rechnen erleichtert liefert Klawun": "Klawun delivers everything
that makes calculation easier."
In 1978 (at the definite end of the SR period, when even Aristo quit!)
'Klawun' was changed into 'Centric'. I don't know if it still exists.
I can't date the rule from this info, although 'Berlin-Charlottenburg' would
indicate 'before 1946', when they moved to Hannover.
Scale indications on business rules often differ from one make to another.
3.6 usually marks a factor for 360 days, the 'bank year'. 'Val.' might be
Valuta(?), the term for currency exchange rates. 'P' must not be confused
with the P scale on a Darmstadt and its further developments!
Looks to be a Nestler Business Rule.
I found a few posts in the archive and am on my way to figuring it
out. Anyway I've got the magifier out and am following thru the
example calculations on the back. Can't read German but business is
business around the world. Seems like a little Beethoven playing in
the background is helping.
Please correct if I have misinterpreted anything.
Marked on body in well:
Albert Nestler A.-G
No.1001/S Berlin-Charlottenburg 5
Lower right face, in italic script:
Der Rechenstab des Kaufmanns, System Klawum
on the back left side:
Feimessinstiut Klawun
Berlin-Charlottenburg 5
Klawum-Rechen-Kurzregein
There is a logo that looks like a combination machinists square and
caliper with Feimess over and Klawun under
on the back right side:
Alles was Rechnen erleichtert
liefert Klawun
from top A/B scales folded at 3.6 (aid for calculations in Imperial
Measure?)
A marked KZ (Kapital + Zins or principal + interest?)
or is the 360
CI marked Val. on left and p% on right (what is Val?, p is interest rate?)
C scale marked E on left and T on right (what is E?, T is Tage, days)
D scale marked V on left and Z on Right (what is V?, Z is Zins, interest)
there is a handy guage mark for PI below the D scale
there are no rear indicators, but the slide can be reversed for
calculations in British pounds and shillings
The paper case is hard to read but there is no Albert Nestler name on
the case. I am suspecting that this rule was made to order for a
technical/business institute.
***************************************
This Faber-Castell was one of many made for Klawun, which resold them on
their own market.
Aristo also made some for Klawun.
***************************************
> 2. Aristo made rules with various other names on them. As John
> Mosand wrote in ISRG posting 16517, Dec. 11, 2002:
> "Aristo made lots of rules imprinted with a distributor's name - for
> export and for domestic distribution. We typically find names like
> Weber, Charvoz, Wichmann and Klawun. Some times they have special #s,
> usually with Aristo's own # as part of it."
> I've never seen an explanation of just who Charvoz was, though their
> name shows up with Post, Roos, etc., as Ted Hume and Paul Ross note
> in several places.
Chris, I've thought of some further factors that might be relevant to
your Klawun rule.
I believe Hannover was in the British zone of postwar occupied Germany,
which may have been an influence on the choice of sterling monetary
scales.
Also, if it has a set of scales split at 360, as suggested by Basil
Orechwa, it would have been to facilitate financial calculations using
a 360 day 'bankers' year'. However, some Faber Castell rules had a
secondary hairline on the cursor which allowed adjustment for 365 day
years. Perhaps the Kawun cursor has a similar hairline.
Of course, scales folded at 36 also aided calculation in the archaic
terms of inches and yards. ;-)
Klawun (spoken claw-VOON (or so)) was a german company founded 1924 in
Berlin. After the war (1946) they moved to Hannover. They built own silde
rules, but also distributed other german slide rules (Nestler and
Faber-Castell). I got this information from
http://www.uni-greifswald.de/~wwwmathe/RTS/rs20035.html (alas only german).
"Der Rechenstab des Kaufmanns" means "the slide rule of the merchant", so
the slide rule is a business slide rule. This explains the britisch
currency scales on it. Can you send the other german writings? Then I will
translate them.
Hopp states <that the Feinmessinstitut Jos. Klawun was in Berlin in
1924, and moved to Hanover in 1946. It became part of the Centric
organisation in 1978. The model No. 1001/s was <der Rechenstab fur
Kaufmanns> (The merchants' slide rule), as the Sterling monetary
conversion scales imply.
> Why do you suppose they moved from Berlin to Hanover in 1946?
Probably because at that time Berlin was already in a fine mess, so
there was no need for a Feinmessinstitut ;-)
Also, it was surrounded by the Soviet zone of occupation, so the
prospective sales for business slide rules would have been better in
Hanover.
Weißer einseitiger Rechenschieber aus Aristopal, mit Platiketui und Bedienungsanleitung, folgende Skalen sind auf der Vorderseite vorhanden L,K,A ! B,BI,CI,C ! D,S,ST,T, auf der Zungenrückseite S, LL2, LL3, die Skalenbreite beträgt 25 cm. Er wurde im Feinmessisnstitut Klawun, Hannover hergestellt. Das Feinmessinstitut Joe F. Klawun wurde 1924 in Berlin-Charlottenburg eröffnet, verlegte nach dem Kriege (1946) seinen Sitz nach Hannover und wurde nach dem Tode von J. F. Klawun ab 1978 unter der Vertriebsregie von CENTRIC (Werner Freise KG) weitergeführt. J. F. Klawun hat sich besonders um den Vertrieb von Rechenschiebern an Schulen bemüht und dabei von deutschen Herstellern bezogene Modelle angeboten, die meist mit Feinmessinstitut J. F. Klawun gekennzeichnet waren. Dieser Rechenschieber wurde im Internet erworben.
Klawurianos Saludos