Re: Signing CAD Software: (WAS Thanks Guys, and a little more on VMS)

[Mr. Reynolds:]

> The subject of signing CAD software caught my eye. Is such software
> available to the general public at a reasonable cost? I am particularly
> interested in BGS design with FWHA fonts.

Adam has already answered your question--basically "No"--but personally
I think what we really need is a version of 'SignMaker' which can
produce fully scalable vector output.

When I was experimenting with sign drawings (mostly to see what
American signs would look like if we adopted bilingualism and changed
our rules for diagrammatic signing), I generally used 'CorelDRAW'
version 9 with the Roadgeek 2000 fonts (which were then all that was
available) and tried to get the dimensions correct using the two-letter
string "Bx" (in Series E) as a sort of try square. (I had to fake
Series E Modified by increasing the stroke width and average letter
spacing of Roadgeek E--I couldn't use Roadgeek EM because my system is
still Windows 98). The results can be viewed here:

http://users.ox.ac.uk/~quee0777/holding/issia-signing-experiments.pdf

(Issia is an imaginary state best thought of as California in the
seventeenth century, before geographers realized it wasn't an island.
It has substantial Spanish- and Vietnamese-speaking minorities but I
didn't learn enough Vietnamese to design bilingual accommodation for
that group.)

In 'CorelDRAW', I found that if one is very careful to check letter and
line spacing and to compare all relevant dimensions with "Bx," one can
produce sign drawings which are quite close to being dimensionally
correct. Indeed, the illustrations in recent 'M.U.T.C.D.' editions and
'Standard Highway Signs' have been produced using that program.

But the software has significant disadvantages. Rectangles have to be
created with the correct dimensions from the get-go, otherwise borders
and rounding are distorted when they are applied. (You can see this in
some carelessly produced state M.U.T.C.D.s and sign drawings books.)
This means "Bx" has to be copied and rotated many times to block out
where the rectangle is to be drawn, and there is much zooming back and
forth to be sure the rectangle corners are precisely located. There
appears to be no provision for creating rectangles "with precision" by
typing values into a dialog box, although it is possible to use Corel
macro language to specify precise dimensions.

I also found that it is desirable to distinguish between outlines which
are scalable and which are not, to prevent line width from becoming too
thin when the sign drawing is rescaled to a small size. Route marker
shield edges are examples of outlines which shouldn't scale, while
borders (assuming two-color drawings) and letter outlines (if used)
should scale. But 'CorelDRAW', it turns out, has a bug--it often
"forgets" which outlines are meant to be scalable and which aren't.

I have toyed with the idea of creating an implementation of the sign
design rules in Corel macro language, which I could then run as a macro
whenever I wanted to produce a sign design. This could be used many
many times to produce, for example, a pattern-accurate exit list. But
I never actually succeeded in getting any of my test macros to run when
I took a first stab on an unrelated project. Plus there is the not
insignificant problem of designing a dialog box which would allow all
of the major sign types to be designed interactively (though I suppose
once the "back end" code was in, it would not be too difficult to
socialize users to produce input text files which specified the sign
designs they wanted in a logical way).

It's also a nice and surprisingly difficult problem to create a correct
border for a full-color sign drawing. With a two-color sign drawing
(black on white), one just starts with a hairline rectangle and
generates the border by adjusting outline thickness. But to produce a
full-color "copy" of this drawing, one has to convert the rectangle
outline into an object and get rid of the inner part of the object (the
inner outline). I don't see an obvious way to do this noninteractively.

.

Relevant Pages

  • Re: Self changing/updating dimensions
    ... happen will calling up old sheetmetal models into later releases. ... 4.Use design tables with the dimensions locked so that only chnages via ... 5.Keep pdf's of all your drawings so you've got something to refer back ...
    (comp.cad.solidworks)
  • B.E Mechanical Engineer (Exposure Steam Turbines, Mechanical Desktop, AutoCAD, SolidWorks)
    ... Current Location: Bangalore ... Fabrication drawings & User Manual preparation related to Steam ... I am involved in the day to day activities of the Design Department's ...
    (sci.energy)
  • Re: Mechanical design software
    ... stamping design. ... I will need to make manufacturing drawings using the models and I'd ... Assemblies and drawings update with part feature changes. ... It's easy to create detail and cross section views on drawings and there is a BOM feature for assemblies. ...
    (alt.machines.cnc)
  • Re: Undesirable Habits of your Co-workers.
    ... He needed to use a skid I designed in Solid ... Then it turned out that my skid design needed many changes to work ... be very hard to make in the 2D AutoCAD drawings he already made. ... vendor, and through our shop. ...
    (alt.machines.cnc)
  • Re: Finally wrote-up my "How to Design Parts" section...
    ... an e-booklet on how to design parts for easy machining. ... Is this something your customers have requested or are expecting? ... If you went to a car dealer to buy a new car, and told the salesman you were looking for good gas mileage, and if the salesman started telling you that he'd seen you drive into the parking lot, and you were doing it all wrong, and here's how you really ought to be accelerating, shifting gears, and using the brakes... ... In the first section, "DRAWINGS AND PRINTS", in the subsection titled "When possible, use solid modeling to create complex part design", the 2D drawing is wrong. ...
    (alt.machines.cnc)