huangyhg

drawing text upper case vs. lower case?
is there a standard or preference for upper case or lower case lettering on drawings today? 30 years ago everything was upper case.
per asme y14.5-1994, para 1.1.5, capital letters are still required.
all caps
chris
sr. mechanical designer, cad
solidworks 05 sp1.1 / pdmworks 05
asme y14.5-1994, para 1.1.5 just provides guidance to the reader in understanding where notes are intended to go on the drawing verses notes that are intended as explanatory only when reading the y14.5 standard. it does not standardize lettering case use for engineering drawings.
asme y14.2m-1992, "line conventions and lettering" is where the requirement for letter case is specified. paragraph 4.3 of this standard states that 'upper case letters shall be used for all lettering on drawings unless lower case letters are required. (see figs 14 and 15)'. figure 14 shows examples of upper and lower case inclined lettering and figure 15 shows examples of upper and lower case vertical lettering.
gdt_guy
gdt_guy,
para 1.1.5 states "notes herein in capital letters are intended to appear on finished drawings. notes in lower case letters are explanatory only and are not intended to appear on drawings." nothing about where notes are intended to go, other than on the drawing.
i do agree however that asme y14.2m-1992 is the governing standard in regards to lettering, as stated in para 1.2. unfortunately for me, i do not have a copy of that standard handy, thus my reference to y14.5.
would you write 4mm, 4mm, or write it out as 4 millimeters?
asme y14.5-1995, para 1.5.3.1 states "where some millimeter dimensions are shown on an inch drawing, the symbol mm shall follow the millimeter values."
i guess calling "mm" a symbol is how they get around the all capital letters rule.
while "mm" is the most common (mechanical) lower case symbol allowed on drawings, there are several others (mostly 'sparky speak' items) like all the hertz abbreviations "hz", "mhz", etc.
the general rule is, if the industry standard abbreviation is either lower case (i.e. "mm") or mixed case (i.e. "hz") use that on the drawing. all else is upper case.
i think the "all upper case" rule stems from 'the bad old days' of (poor) hand lettering and the "4th generation copy must be legible" requirement. all 'ancient history' in these days of cad and excellent copiers.
redpen
also see mil-std-12 (s/s by asme-y14.38m) abbreviations for use on drawings, and in specifications, standards and technical documents
chris
sr. mechanical designer, cad
solidworks 05 sp2.0 / pdmworks 05
y'all may also want a copy each of the following:
geo-metrics iii : the application of geometric dimensioning and tolerancing techniques (lowell foster)
and...
ansi y1.1 (latest edition) abbreviations for use on drawings and in text.
chris in nc

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