After trying many software and techniques to make PCBs, I thought I would share my conclusions (wich may elolve):
My X-Carve has a backlash of 0.15mm on the X axis ans 0.045mm on Y axis. This limits PCBs desing to 100mil (2.54mm) DIP packages, no traces between legs. I could not find any info on how to reduce this backlash. I must say here that this backlash corresponds exactly to the advertised precision anyway, so I’m not saying I’m not satisfied with the X-Cave as it does as expected. In fact, my 0.045mm only backlash on Y axis is some kind of a bonus. It seems to be the limit of the GT-2 belts. So it does make oval circles intead of round, unless you compensate the backlash in your desing (be adding 0.15mm and 0.45mm on respective axis) or use another CNC controller that compensate the backlash. Actually, gSheild does not include such parameters. Of course, 0,15mm on a 4 inches circle is not really an issue. But on a 1.5mm PCB pad, it can be problematic. So I hat to find tools that would allow me to precisly define traces width and pad shapes, etc.
But it works and it’s very usefull and fun.
On the software side, after using eagle for years and trying hard on multisim/ultiroute for schematic and board routing on my x-carve, I opted for this software (new to me) DIPTRACE, wich is much more adapted to my needs (x-carve pcbs), simpler (but can go as deep as the others), much more natural modern interface, etc. I think this is what makes it so much better that the others: the user interface. The free version is more generous than eagle’s free version and the full version costs less. Creating custom parts is very easy and straight forward. I could go on and on. Really worth giving it a try as the learning curve is very natural.
DipTrace allowed me to precisly and easily control trace and pad width, wich I never really did with success in eagle and the ulp Gcode plugins or using Chilipeppr eagle board import widget. DipTrace allowed me to define my own parts (based on parts in the existing database) with larger pads, etc. This is important with the X-Carve beacause of it’s backlash issue, particularly if I need to make 2 sided PCBs. This prevents traces and pads to be thinner than expected, a problem that can ruin a PCB.
Then I export my gerber files to Flatcam. Very nice software also. This is where traces, drills and pads are translated to GCode. Note that I found a little issue with drills in FlatCam: imported drills from PCB board software (Diptrace or Eagle etc) MUST BE SCALED x10 in FlatCam (there is a function for that- usi it!) or the drills get shrinked at the bottom left of the desing) I’m working in mm, I don’t know if it ok in inches.
Finally, I use ChilliPeppr for it’s autolevelling function. This helps make thinner cuts. I measured my cuts to have a width of 0.33mm with a 45 degre V bits at 0,045mm cut depth. This allows me to make 2 sided PCBs that works great.
If some poeple are able to make more precise (small SMDs) PCBs with their X-Carve, I would like to know how they got that precision level.
I will try to post some pics later.