Mechanical CAD for Linux LG #33

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I am a Mechanical Engineer and an owner of a small business, L&D Technologies, 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 SGI(TM) or UltraSPARC2(TM) machine (even though that would have been perfect), so my options were down to which operating system I would be running my PC under.

I had two options:

Doing the preliminary cost estimate comparison between these two options, I quickly ruled out Windows(TM)-based system.

And so my search began for a production quality mechanical CAD system that would run under Linux, and be reasonably priced.


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 VARKON, for example) or were too simplistic for production drafting (otherwise very good xfig/transfig combo). I have also looked into Bentley’s Microstation (TM)( for Linux, but they only offered educational licences at the time ( a move I will never 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- FREEDraft project. It is an attempt to bring to life a GNU drafting package, and I wish those people the best of luck in future development.

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 page posted here, which comletely turned me away from LinuxCAD. I went to VariCAD’s USA site instead, and quickly found out there is a working demo (without Save features) available for a download.

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:


Obtaining And Installing The Software

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 Red Hat distribution of Linux.

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 which requires one to log in as root for it to work. On my system trying to execute the 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 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.

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 Xfree86 windowing system, with xserver-mach64 running in the 1152×864 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

Using The VariCAD

Before going any further, I would like to say that my exposure to AutoCAD (TM) 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 E-mail me your short review in an HTML format, and I’ll post it here or send me an URL pointer to your page.

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):

~$ ps aux


dnaden 2406 11.4 2.7 4844 1760 1 S 22:16 0:02 /usr/bin/varicad

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…

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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.

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…).

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 « wrong » 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.

Developers have been smart enough to include in the « core » 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 their site 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.

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 « imagined » 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.

People Behind The Software (Support)

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.

Other User’s Opinions On VariCAD

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… 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.

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.

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