X-Carve's capacity for PCB manufacturing

I live in an apartment with hardwood floors and limited carpeting. My neighbor, who enjoys bass-heavy music everynight, asked that I keep the CNC off after 10pm.

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I think I would tell him Iā€™ll stop running my machine when he shut off his loud music. We have cars go by on the highway that we hear the stereo 1/2 mile before they are out front and a 1/2 mile after they pass.

Dave

Hi Sketch42, What size is your X-Carve (500mm or 1000mm) to get 0.002" precision?

Itā€™s a 1000mm

I just work on smaller projects with tighter precision in a cornerā€¦ But given time, patience, thought, and a good standard to measure against either X-Carve should be able to perform with a decent level of accuracy.

It also helps to calculate speeds and feeds based on slow movement rather than how fast can the job be done.

Thanks sketch42.

I am hesitating on upgrading my order to a 1000mm. I will mostly make PCBs, but would like to have the possibility make bigger projects. I assumed the 500mm would be more precise, but I donā€™t have any real data to back this assumption. What are the tests you made to report a 0.002" precision?

Thanks again for your time.

It is possible that the 500mm when dialed in might be more precise. I donā€™t know, but I would think that it would be easer to ā€œdial it inā€ compared to the 1000mm. It has taken many tweaking sessions for me to get mine to where it is. I too will be working mostly on smaller projects, but from time to time I will carve a chair or large box and will be glad to have the space to do it.

The way I am checking tolerance on my carves is looking for places on my finished carves where I know a value to be a specific amount and then measure it with calipers to check that it is in fact that size. On smaller and slower projects it is usually pretty close. For example, on a wall for a case that I milled last night, the cad file says the wall should be 1.8mm and the calipers on the actual wood piece measure 1.80mm in 3 of the 5 spots that I checked and 1.81mm in 1 spot and 1.79mm in another spot.

@KyleJacobs, what size X-Carve are you using?

Iā€™m using a shapeoko 2 with the z-axis motor plate upgraded to x-carve (I havenā€™t gotten around to fully disassembling the SO2 to scavenge the v-wheels yet), at the 500mm size.

Thanks Sketch42.
I will keep the 500mm order.

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Greetings, I am following the conversation and see that you speak of the Eagle to make PCB, then a Gcoder, but Easel not support Gcode, how you do that the x-carve make the cut?

You can use another program to send the gcode, like Chilipeppr or Universal Gcode Sender (UGS).

Chillipeppr reads eagle files directly. It also have a function to probe PCB surface height. I have not done any pcb yet (still tuning the machine) but chillipeper looks very promising to me.

Wow- I had no idea that Chillipeppr could lead an entire Eagle file directly. Thatā€™s pretty amazing. I just purchased my X-Carve this morning, so in about a month my first goals will be setting up the machine for probing in Chillipeppr and milling PCBs, then sharing my results.

Hi, I would like to know more about pcb making using XCarve. What is the advantage of X-Carve over Rolland Modella.
How to level waste board for pcb milling.

you can level the wasteboard by milling it flat with a large endmill.

After testing pretty much that functionality in Chillipeppr, I could not make it work properly. I now use DIPTRACE (schematic/board layout - VERY VERY cool), then FLATCAM and Chillipeppr in the end (autoleveling is great).

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 Iā€™m not saying Iā€™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 itā€™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 eagleā€™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 itā€™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) Iā€™m working in mm, I donā€™t know if it ok in inches.

Finally, I use ChilliPeppr for itā€™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.

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By switching controller you can remove (allow for) the backlash. I use the Planet CNC MK3 controller and it allows me to measure and allow for backlash. This has drastically improved the results of my PCB milling and fine detail milling over all. I founr I had about .0100 on X and Y (not sure the exact number off top of my head, .01 and change) I also found that the stock values for the SPU were NOT acculturate when measured with a digital indicator dial. There were in fact off by about .23mm or so on one axis on the X carve and about .12 or so on the other one. The Shapeoko 2 fared about the same. Correcting for the right SPU on each axis and then measuring for backlash has gotten all the axis within .03-.06mm . This is tested my loading the dial calibrator, zeroing it and the mill, running 23mm AWAY from the indicator then back to zero, then -23mm. then back to zero. all measurements fell with .03mm Ā± of the desired measurement. So there are controllers out there that can allow for the backlash and fix it. There are also a few very good engraving bit for PCB milling that will get your traces down a bit smaller and when paired with the MK3, really allow for some very nice detailed boards to be made. I need to remill the test board in my PCB tutorial as I have since purchased and used a much better digital indicator dial and measured the backlash better. The mill now cuts an extremely round circle and no longer slightly oval ones.

100% on FlatCam and I will have to check out Diptrace. I left Chilipeppr for the PlanetNC software when does a great job of auto leveling and has yet to crash on me in hundreds of hours of milling (some jobs running 9+ hours in aluminum).

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Hi,
I was trying to do PCB milling and I could find two projects in inventables about PCB milling.I followed the steps as mentioned. Created a gerber File using Eagle and used FlatCAM to generate gcode. Next step was auto leveling using Chilipeppr. It was my first experience with chilipeppr and I faced my first trouble here, I couldnā€™t do auto level because bit stopped moving even before it touched the PCB . Then I found out it was due to noise. So I twisted the probes and things became normal and I could do auto leveling without any trouble. But when I sent the leveled gcode for job, machine came to zero position and started moving as it was supposed to do but it is not touching the PCB surface. It just moves around the surface with tiny gap between board and bit (gap is so small) . Result no engraving.
I tried it several times but still no use.
I am using GRBL not TinyG and my threaded rod is M8.
I donā€™t know which is the default z axis parameters in chilipeppr and I couldnā€™t find any provision to change the screw type in chilipeppr( in Easel there is an option to choose the rod M8 or Acme).
Seeking all advice and opinions about solving this.
Thank you

Just finished a PCB as a test, and Iā€™m damn impressed. Itā€™s through-hole, but typical of what I do now.

Found that FlatCAM did not seem to handle round boards, so I printed to PDF from my layout app, brought that into Inkscape for a flood-fill to make the isolation layer, then pulled that SVG into Estlcam, traced everything out, and added the drill holes.

The isolation layer was cut to 0.002" deep with a 0.008" x 30Ā° engraving tool. The small holes were pecked with a 1/32" end mill, the larger holes were helical drills with a 1/16" end mill, and the outline was done with an 1/8" end mill. No special flattening of waste board, or 2D probing was done before.

Only one screw-up! Can you spot it? :wink:

Edit: Added pics and video.