Hi! Long time user of Orcad Allegro but now retired and want to make some hobby pcb’s. I still have my own Orcad but it doesnt run under Linux Mint so I was told checkout Libre. Very nice looking package! So I use a few low price pcb houses and with my Gerbers they like to see a dxf or pdf of the pcb dimensioned. I usually do it within Orcad or export it as a dxf then use my CAD program to do it. I dont see any dxf export options with Libre. How would I produce a dimensioned pcb drawing?
Currently there’s no DXF export. Probably you could export the board outlines as SVG (with the output job “Board Assembly PDF/Image” with only the outlines layer enabled) and then convert the SVG to DXF with an external tool (maybe LibreCAD can do this).
Or theoretically you could draw any dimensioning drawings on the “Measures” layer in the board editor, and then export directly a PDF with both the outlines layer and the measures layer (same output job as above). But I would not recommend this since drawing the dimensioning manually is cumbersome and error-prone. Generally the PDF export is intended to create assembly plans, not containing any dimension numbers.
However, to be honest I wonder if you really need it. The board outlines is of course exported to the Gerber files and this should be the single source of truth for the PCB manufacturer. If you provide them an additional file with the outlines, things can only go worse, not better. So far I have never seen a PCB manufacturer who insists in receiving a separate file for the dimensions. May I ask which PCB manufacturers you intend to use?
Yea I didnt think there was a way. Yes drawing it manually is not the way to go either. As far as needing it I always made one to be included with the Fabrication drawings. It was always required from the the board houses I used in US,China,German,France and Romania as my pcb’s had cut outs….slots….ect and they wanted very detailed drawings showing the radi’s,cutout/slots dims…all from the zero datum…tolerances for all of those. They also wanted all mounting holes dimensioned with tolerances shown. Plus all the other fab info they need. My later versions of Allegro did all of that within that package (of course it was a $$$$ package!) but my earlier versions we’d export it all as a dxf and the mechanical dept would make up the drawings. Later I learned to do it too.
I did bring up in my early days what was the need for so much info as it was a lot of work…esp when we had layoffs and I had to now take on that work? All of the pcb houses sent me back lists of issues they have seen trying to depend on the Gerbers only being correct all the time. Some issues were hard to believe it happened. But must keep in mind my orders went from $20K to $200K so there were tons of checks in place.
As far as the hobbyist level stuff I only used one company in the US and they did ask for a complete fab drawing which kinda amused me as they were building the pcb’s according to their whims on whatever was being made that day! It could be .062 or .093…or HASL or lead…purple or green mask…ect. But that company went out of business this year so now I was told to try PCBWay…I have yet to contact them to ask what their file requirements are.
My buddy uses Kicad which he says has the ability to make the Fab dwg like I used to….but he said while it runs under Linux Mint it doesnt run well at all under Mint Cininmon which is what I use. Huh….I didnt think of looking into that with Libre pcb.
Generally I understand some things can make sense as a drawing, e.g. tolerances, marking plated board edges or other special processes which cannot be safely expressed in Gerber files. But I really don’t get the point to document separately what is already in the Gerbers (dimensions, tool diameters, etc.). But yeah if they ask for such documents we have to bite that bullet…
I think DXF export will be a reasonable feature request anyway, probably we will implement that sooner or later and should be sufficient to create such drawings (just not as automated as the $$$$ Allegro). In the mean time this can probably be worked around by just using SVG instead since it is also vector based and contains exact coordinates.
For PCBWay you even don’t have to worry about file requirements. With our fabrication service you can order LibrePCB projects at PCBWay right from the application, no need to worry about Gerber files at all.
I see no reason why LibrePCB should not work well on Mint, but honestly I also don’t see a reason why KiCad shouldn’t. IMHO the decision about LibrePCB vs. KiCad should be rather based on which software suits you more.
I agree as they also wanted me to include on the Fab dwg the drill files. Uhh why would that be needed as its made from the Gerber file that is being sent. I did see once an issue with one guys Gerbers had an old Rev outline file that didnt match his new pcb gerbers. When he was making his gerper.zip file he grabbed an old one. They caught it when it didnt match the drawing. Later on the software made it impossible for that to happen. But as you pointed out…if they want it…they want it. For me…I no longer have access to my old CAD package and I have little time now to learn that too. Though down the road I wouldnt mind having one to use. So I’m hoping what house I use they dont need that info.
Thanks for the info PCBway!
I guess the Linux Mint issue and Kicad is only with the “flavor” I picked…Cinnamon…something with graphical issues. But other Mints work fine. And my latest rev might be okay now. I looked at Kicad…..but I liked Libre better so I rather stick with that package. I have it loaded and soon will start playing with it doing a simple pcb. Should be fun!