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<TITLE>Mechanical CAD for Linux LG #33</TITLE>
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<META name="Modified" content="13-09-1998 12:43:42">
<META name="Author" content="Damir Naden">
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"Linux Gazette...<I>making Linux just a little more fun!</I>"
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<H4>By <a href="mailto:ldtech@istar.ca">Damir Naden</a></H4>
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<H2><A name="intro"></A><FONT face="Lucida,Helvetica">INTRODUCTION</FONT></H2>
<HR>
<P><FONT face="Lucida,Helvetica">I am a Mechanical Engineer and an owner of a small business, <A href="mailto:ldtech@istar.ca">L&amp;D Technologies</A>, specializing in mechanical design and drafting and project management of small to medium size projects in mechanical engineering field. As any small business owner knows, the cost of start-up can be quite high, especially in the field where high end workstation and 3-D software are very important. I knew that I couldn't afford the <A href="http://www.sgi.com/">SGI(TM)</A> or <A href="http://www.sun.com/">UltraSPARC2(TM)</A> machine (even though that would have been perfect), so my options were down to which operating system I would be running my PC under.</FONT></P>
<P><FONT face="Lucida,Helvetica">I had two options:</FONT></P>
<UL>
<LI><A href="http://www.microsoft.com/">WindowsNT(TM)</A>- which I use at my other, daytime job, and thus already have a very good understanding of the CAD software available on this platform ( <A href="http://www.cadkey.com/">CADKEY(TM)</A> and <A href="http://www.ptc.com/">Pro/E(TM)</A>)
<LI><A href="http://www.debian.org/">Debian/GNU Linux OS</A>- which I use on my home computer
</UL>
<P><FONT face="Lucida,Helvetica">Doing the preliminary cost estimate comparison between these two options, I quickly ruled out Windows(TM)-based system.</FONT></P>
<P><FONT face="Lucida,Helvetica">And so my search began for a production
quality mechanical CAD system that would run under Linux, and be reasonably priced.</FONT></P>
<HR>
<H2><A name="search"></A><FONT face="Lucida,Helvetica">SEARCH</FONT></H2>
<HR>
<P><FONT face="Lucida,Helvetica">I have used Linux for three years, and all
that time the available applications and their quality have
constantly been improving. I have felt that the only field where
Linux was thin in available applications was mechanical
engineering. True, there have been some CAD apps out there, but
they either required too much programming (very powerfull <A href="http://www.microform.se/">VARKON</A>,
for example) or were too simplistic for production drafting
(otherwise very good xfig/transfig combo). I have also looked
into <A href="http://www.bentley.com/academic">Bentley's Microstation (TM)</A>(
for Linux, but they only offered educational licences at the time
( a move I will <U>never</U> understand: who would get an
educational licence for a piece of software they can not continue
using after graduation- at least not under the same OS-?). Just
for the record, I think the Microstation(TM) could blow away
anything offered for Linux in this field, if they had some
management vision and interest in developing for Linux community.
One other site is worth mentioning, if for nothing else but for
more exposure of this project to other Linux users- <A href="http://pw2.netcom.com/~iamcliff/FREEdraft.html">FREEDraft project</A>. It is an attempt
to bring to life a GNU drafting package, and I wish those people
the best of luck in future development.</FONT></P>
<P><FONT face="Lucida,Helvetica">Then I have noticed two new entries in the
software arena, LinuxCAD and VariCAD. I have almost purchased
LinuxCAD (at $75, it seemed like a great deal), but didn't like
the fact they had no demo available, and their E-mail reply to my
preliminary inquiry had amounted to a little more than
self-promoting junk mail. Only a couple of days later there was a
usenet discussion about LinuxCAD and result was a <A href="http://www.ssc.com/lg/issue30/wuest.html">page posted here</A>, which comletely turned me away from LinuxCAD. I went to <A href="http://atlanta.varicad.com/">VariCAD's USA site</A> instead, and quickly found out there is a working demo (without Save features) available for a download.</FONT></P>
<P><FONT face="Lucida,Helvetica">If you are interested in doing a search for
available apps for Linux on your own, I recommend following sites
as a good starting point:</FONT></P>
<UL>
<LI><FONT face="Lucida,Helvetica">very good for scientific applications:<A href="http://SAL.KachinaTech.COM/"> Kachina Technologies site</A></FONT>
<LI><FONT face="Lucida,Helvetica">for general linux application: <A href="http://tsikora.tiac.net/linapps">linux applications mirror site</A></FONT>
</UL>
<HR>
<H2><A name="varicad"></A><FONT face="Lucida,Helvetica">VariCAD FOR LINUX</FONT></H2>
<HR>
<H3><FONT face="Lucida,Helvetica">Obtaining And Installing The Software</FONT></H3>
<P><FONT face="Lucida,Helvetica">Download
consisted of getting four tarred files, and amounted to about
5Mb, which is very reasonable for a CAD system, along with the
installation script. Available for the download is also RPM
package, which must be downloaded as a roughly 5Mb single file,
and it represents a nice touch for people running <A href="http://www.redhat.com/">Red Hat</A> distribution of Linux.</FONT></P>
<P><FONT face="Lucida,Helvetica">Installation instructions, for people who
choose to get the plain tarred files, are very simple and clearly
stated at the download site. I have simply followed those
instructions, and it worked like a charm with version 6.1. As of
a Aug. 29 1998, they have released new version, 6.2-0.3, and in
my experience, there is a small glitch in installation script
inst.sh which requires one to log in as root for it to work. On
my system trying to execute the inst.sh script under su did not
work; only 'true' root login managed to install the program.
Also, the tarred files had been deleted in the installation
process, so if you want to have a backup on the floppies, be sure
to copy tarred files someplace else first, before executing the
inst.sh script. This didn't happen with the version 6.1, though.
On the other hand, new version (6.2-0.3) seems to be more robust,
and it adds a drop-down menu for Internet access, which I haven't
tested yet.</FONT></P>
<P><FONT face="Lucida,Helvetica">Since I'm running the Debian distribution, I
would have liked to see the option in the installation process
for choosing the target directory, and would have rather placed
the VariCAD under /usr/local tree than under the default /usr
tree. On the other hand, after installation script had completed,
executing varicad command for the very first time in the rxvt
resulted in a flawless start. I'm running the <A href="http://www.xfree86.org/">Xfree86</A> windowing system, with xserver-mach64 running in the 1152x864
resolution and 32 bpp, and VariCAD didn't seem to have a problem
with those settings. After I have been playing with the software
for a week, I decided it was worth the price they are asking for
it and, after I have mailed in the cheque, received a small file
in an E-mail which enables the save feature. As per instructions
in the E-mail I copied the file to the /usr/lib/Varicad tree and
at the next start of the program, the pop-up message about demo
nature of the program went away, and I could happily save files
and settings</FONT></P>
<H3><FONT face="">Using The VariCAD</FONT></H3>
<P><FONT face="Lucida,Helvetica">Before going any further, I would like to say that my exposure to <A href="http://www.autodesk.com/">AutoCAD (TM)</A> has been limited to version 10, way, way back, and if
you are expecting the direct comparison between Mechanical
Desktop (TM) and VariCAD, I'm afraid you will be dissappointed.
If you are using AutoCAD and have given VariCAD a try, please <A href="mailto:ldtech@istar.ca">E-mail me</A> your short review in an
HTML format, and I'll post it here or send me an URL pointer to
your page.</FONT></P>
<P><FONT face="Lucida,Helvetica">Because VariCAD does not use the Motif
libraries, the executable is rather small and efficient. Fired up
and having a rather simple 2-D drawing running, VariCAD toll on
the system's resources is rather small ( output from ps on my
system running VariCAD):</FONT></P>
<P><FONT face="courier">~$ ps aux</FONT></P>
<P><FONT face="courier">USER PID %CPU %MEM SIZE RSS TTY STAT START TIME COMMAND</FONT></P>
<P><FONT face="courier">dnaden 2406 11.4 2.7 4844 1760 1 S 22:16 0:02 /usr/bin/varicad</FONT></P>
<P><FONT face="Lucida,Helvetica">The interface is very plain which is a plus
in my opinion. Starting with ver. 6.2-0.3, the 'tool-tip' style
description is available for all the buttons of the toolbar,
which is a very important feature if you are just strarting to
use the software. On-line manual is available from the drop-down
menu, and it is very complete. Some parts suffer from
less-than-optimum english translation, but I haven't found that
to be in a way of getting the gist of the information through.
Then again, my english is not perfect, either...</FONT></P>
<P><FONT face="Lucida,Helvetica">Sytem starts up in a 2-D mode, and switching
into the 3-D mode is a matter of simple click on the icon in the
top right-hand corner. Default toolbar features the icons for
drafting functions, and paging through the toolbars for other
functions ( dimensioning, for example) is done by clicking on the
respective icon in the bottom part of the toolbar. All toolbars
seem to be of the tear-off variety, but I haven't tested that
extensively ( I like my interface clean). And all the functions
are available through the drop-down menus as well.</FONT></P>
<P><FONT face="Lucida,Helvetica">First thing I have noticed is that panning
and zooming back and forth is done fast. A simple subjective
comparison between very similar machines running CADKEY (TM)for
Windows(TM) v.7.5 (under WinNT(TM)) and VariCAD v6.2-0.3 under
Debian/GNU Linux v.2.0 would suggest that VariCAD is slightly
faster in redrawing the screen. Another feature I like is the way
zooming and panning work (users of Pro/E should feel at home
here): dragging the mouse ( and having the Shift+LMB pressed) up
and down zooms in and out, respectively, and dragging the mouse,
having the Control+LMB pressed, does the panning. It is very
convenient feature when you get used to it. And if you get lost
in all this zooming and panning, there is a feature called Aerial
View, which brings up a small window with the overview of the
entire drawing area and highlights the square you are in at that
moment in the main window ( I believe I have seen same feature in
AutoCAD Lite(TM)...). Other noticeable feature ( for me at least)
enables one to highlight the feature when the mouse cursor is
over it. If you ever worked with lots of lines spaced close to
each other, you will learn to appreciate this. It can also
highlight feature's significant points (i.e. end- or mid- point
of the line, center of the circle and so on) by popping up a
small code when your cursor is on top of it. I haven't had that
in CADKEY(TM), so it will take me some time before I can remember
all the symbols and their meaning, but AutoCAD(TM) users should
be familiar with them ( for example, @ for the center of the
circle...).</FONT></P>
<P><FONT face="Lucida,Helvetica">Otherwise, VariCAD seems to have all the
drafting, geometric tolerancing and dimensioning functions one
would expect to find in a decent CAD package. In addition to
that, there is a macro language, which I haven't had a chance to
try yet, rather complete 3-D kernel (see some screenshots from
VariCAD's site) and ability to import DXF and IGES formats. I
have imported a 1.2Mb DXF file from CADKEY(TM) without a lost
line, but dimension text was angled, and it could not be edited.
But, as I said, I used CADKEY (TM)to export the file, and
therefore the file is being translated twice, and it is hard for
me to determine which one is &quot;wrong&quot; translation. I
haven't tried to optimize the translator in VariCAD either.
Translation itself is transparent, which means that as soon as
you read the DXF or IGS file, VariCAD produces its native (dwb)
file on which you continue to work. To translate the file to DXF
from within the VariCAD, just save the file with a DXF extension.
As simple as that.</FONT></P>
<P><FONT face="Lucida,Helvetica">Developers have been smart enough to include
in the &quot;core&quot; software a database of Parts, consisting
of nuts, bolts, washers, pins and SKF bearings. Also a part of
the package is a calculation program for calculating spur and
straight bevel gears, splines, shafts, bearings and compression
and extension springs, as well as the V-belt drives. ( I have
probably missed some other elements in here. Check out <A href="http://www.varicad.com/gallery.htm">their site</A> for full
description...) There is also a possibility of creating the
information needed for making the BoMs, although I haven't
touched that yet myself. I also haven't had the need to print
anything as of yet; most of my jobs are being sent in a DXF
format on a floppy.</FONT></P>
<P><FONT face="Lucida,Helvetica">The only gripe I have with the software is
that I can't seem to be able to find out how to dimension to or
from &quot;imagined&quot; intersection. I frequently need to use
the dimension from this or that edge to the intersection of the
chamfered or radiused corner, and I can not get VariCAD to
recognize that I want to use the point where two lines would have
intersected each other, had it not been for the radius for
example, as one of the references for the dimension. If anyone
knows how to do it, please let me know.</FONT></P>
<H3><FONT face="Lucida,Helvetica">People Behind The Software (Support)</FONT></H3>
<P><FONT face="Lucida,Helvetica">I have found people at VariCAD to be knowledgable and courteous.
Everyone, from sales rep in Canada to their HQ in Checz Republic,
had answered my e-mails within 24 hours. As an example: in the
6.1 version, there was a bug in vertical dimensioning when using
the toleranced dimension (the dimension line would not break
around the text, but go right through the text). I have written
an E-mail about it to their tech support, and within 12 hours, I
had an answer- they were aware of it, and it happened only in
inch drawings, not in metric ones, and will fix it in upcoming
6.2 version. Fair enough, I thought... About a month later, on
the very day of the new version release, I have received an
E-mail (from the same tech support guy) notifiying me that the
new version is available for download, and the bug I have asked
about had been squashed. That is what I consider a good customer
service.</FONT></P>
<H3><FONT face="Lucida,Helvetica">Other User's Opinions On VariCAD</FONT></H3>
<P><FONT face="Lucida,Helvetica">In a couple ow weeks my mCAd page was up, I have already received a couple of E-mail responses from other VariCAD users. Thanks for your input. Keep it coming...
<BR>
One user had a problem with too much mousing (not enough command line input) in the earlier (but don't know which) version of variCAD and didn't try it since. I know there is a command line input, but as I said, it is not straight *utoCAD copy, so some commands may need re-learning. And also the quality of the help files was questioned, but I maintain that is mainly a language barrier. We English speaking folks take the fact that everyone knows English too much for granted.
<BR>
The other E-mail was regarding the inconsistent volume calculator. I
can not attest or deny that, as I didn't use 3-D enough as of yet, and VariCAD
allegedly claims they have had no such problems.</font>
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<center><H5>Copyright &copy; 1998, Damir Naden <BR>
Published in Issue 33 of <i>Linux Gazette</i>, October 1998</H5></center>
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