Help needed for pcb milling. Can't get my machine work!

Ok. I hope here is someone who can help me out. I have cheap Chinese 1610 cnc mill what I use for pcb milling. The machine was working fine before, but little while back. my Card get broken. I bought new card and it is Cronos Maker gbrl 1.1 card. After I change the card. machine started working. But every time I try to cut pcb it cutting so near traces that I don't have any traces left. My design has 0.4 mm traces but it it cutting all off.

I have try adjust settings but nothin helps. Desings is made with kicad and plotted as Gerber files. Gerber files are made to Gcode with Flatcam and I use Chilipepper to run decode and machine.

I have no ida where is the problem. I use 0.1mm 30 degree V shaped bits, and cutting depth is 0.05mm to 0.07mm. I have try to make isolation with one pass and 3 passes, but results are always same. I try attach picture here. Here is my Grbl settings.

$0=10
$1=25
$2=0
$3=1
$4=0
$5=0
$6=0
$10=3
$11=0.010
$12=0.002
$13=0
$20=0
$21=1
$22=1
$23=0
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=10000
$31=0
$32=0
$100=800.000
$101=800.000
$102=800.000
$110=800.000
$111=800.000
$112=800.000
$120=20.000
$121=20.000
$122=20.000
$130=160.000
$131=100.000
$132=45.000

and picture in attachment...

I really hope someone can help me out!

-Miikka

I do not know what the problem is, but I am sure it is not the grbl controller.
If you have a backup of the old grbl settings use them.
You could try an old gcode file to see if the results are as before.

Quote:

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Originally Posted by hfjbuis

I do not know what the problem is, but I am sure it is not the grbl controller.
If you have a backup of the old grbl settings use them.
You could try an old gcode file to see if the results are as before.

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Actually, I got some better results today when I change in Flatcam tool diameter to 0.4mm, but this should not be right I think? Still feels the diameter of the trace is smaller than 0.4mm what I was use when I make the board... But I'm agree with you that it is not the problem of grbl controller. The settings is about same than my old controller card.

Hard to tell from your photo, but you might be cutting too deep. That's why your actual cutting diameter is much larger than the theoretical 0.1mm (although 0.4mm still sounds too much).

Another factor is the spindle/collet runout. What kind of spindle do you have? If it's just a DC motor with sleeve bearings and an ER11 chuck slapped on, it would be challenging to get consistent results.

Try cutting just one straight line to see what kind of cutting width you are actually getting.

Quote:

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Originally Posted by CitizenOfDreams

Hard to tell from your photo, but you might be cutting too deep. That's why your actual cutting diameter is much larger than the theoretical 0.1mm (although 0.4mm still sounds too much).

Another factor is the spindle/collet runout. What kind of spindle do you have? If it's just a DC motor with sleeve bearings and an chuck slapped on, it would be challenging to get consistent results.

Try cutting just one straight line to see what kind of cutting width you are actually getting.

---

I was thinking that as well, but I have normally use as tool diameter 0.13 to 0.2 depends how deep I cut with the 0.1 30 degree cutting tool. 0.4 mm. cutting depth is 0.05mm to 0.07 mm. I was even try once 0.1 but that is too deep. Yesterday, after I posted this I tested that 0.4mm cutting diameter. and none of the traces were broken. But it seems really wide area around the traces and like I say traces still looks smaller than 0.4mm. I try to post picture here when I get some results.

The spindle is Chinese model 755 there is no ER11 its more cheap model. Like the one where is just 2 screws keeping it to spindle and other end with two screws keeping the bits. see in picture.. :)

Just in case, post your g-code file. Let's see if you have any problems there.

The motor is not the best for sure, but sometimes we have to work with what we have available. You should still be able to make usable PCBs with it.

Stupid question: is your tool certainly intact? Because the thing 0.1mm v-tips love to do is snap a bit of the tip off and instantly become, say, 0.25-0.30mm v-tips, without this ever becoming particularly obvious unless one inspects the tip and/or compares it with a brand new tool under a magnifier. A related question is how do you hold down your PCB, and where/how do you set your height zero? Is it possible that whatever would be 0.07mm deep wherever you originally set it is actually a lot deeper where you do the milling? Because there is no such thing as a "flat" mill table when PCB milling is involved...

Quote:

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Originally Posted by blinkenlight

Stupid question: is your tool certainly intact? Because the thing 0.1mm v-tips love to do is snap a bit of the tip off and instantly become, say, 0.25-0.30mm v-tips, without this ever becoming particularly obvious unless one inspects the tip and/or compares it with a brand new tool under a magnifier. A related question is how do you hold down your PCB, and where/how do you set your height zero? Is it possible that whatever would be 0.07mm deep wherever you originally set it is actually a lot deeper where you do the milling? Because there is no such thing as a "flat" mill table when PCB milling is involved...

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This is not stupid question at all. But yes, tool is intact and works fine. Manage get better results when I use in Flatcam tool width 0.45mm. Tool is fine and I checked with new tool, no difference. Small edit. If the tip of the tool snap off after you start milling and because I use auto level option, It would not mill at all because its moving above pcb surface...

I hold PCBs down with hard double sided tape.

I set Z to zero first getting it near as I can to the pcb and I run Auto level with chilipepper software. That put zero exactly on surfice of the pcb...

Quote:

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Originally Posted by MikiL

This is not stupid question at all. But yes, tool is intact and works fine. Manage get better results when I use in Flatcam tool width 0.45mm. Tool is fine and I checked with new tool, no difference. Small edit. If the tip of the tool snap off after you start milling and because I use auto level option, It would not mill at all because its moving above pcb surface...

I hold PCBs down with hard double sided tape.

I set Z to zero first getting it near as I can to the pcb and I run Auto level with chilipepper software. That put zero exactly on surfice of the pcb...

---

Hi Miki,

Let me point you to a site with member's using exactly your CNC machine for help.

https://github.com/martin2250/OpenCNCPilot

https://github.com/martin2250/OpenCNCPilot/issues/28

Hope that site should resolve your issues.

Cheers,
Hanspeter.

Quote:

---

Originally Posted by MikiL

I have try adjust settings but nothin helps. Desings is made with kicad and plotted as Gerber files. Gerber files are made to Gcode with Flatcam and I use Chilipepper to run decode and machine.

I have no ida where is the problem. I use 0.1mm 30 degree V shaped bits, and cutting depth is 0.05mm to 0.07mm. I have try to make isolation with one pass and 3 passes, but results are always same. I try attach picture here. Here is my Grbl settings.

$0=10
$1=25
$2=0
$3=1
$4=0
$5=0
$6=0
$10=3
$11=0.010
$12=0.002
$13=0
$20=0
$21=1
$22=1
$23=0
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=10000
$31=0
$32=0
$100=800.000
$101=800.000
$102=800.000
$110=800.000
$111=800.000
$112=800.000
$120=20.000
$121=20.000
$122=20.000
$130=160.000
$131=100.000
$132=45.000

and picture in attachment...

I really hope someone can help me out!

-Miikka

---

Hi Miki,

Here are my GRBL settings, but careful not to copy everything as my stepper direction in my settings could be different from yours.
Should give you a starting point if you are over/under setting your stepper drives.

$0=25
$1=255
$2=0
$3=1
$4=0
$5=0
$6=0
$10=3
$11=0.010
$12=0.002
$13=0
$20=0
$21=1
$22=1
$23=0
$24=25
$25=60
$26=250
$27=1
$30=12000
$31=0
$32=0
$100=400
$101=400
$102=400
$110=1000
$111=1000
$112=450
$120=100
$121=100
$122=60
$130=250
$131=300
$132=45

Cheers,
Hanspeter.

Having similar problem, post is a little after yours, slightly different machine, using gSender and sometimes cncjs in place of Chilipeppr, they both jog well and the latter also has good manual spindle control, I found this essential for placing alignment pins. There is a setting in the isolation routing for % and # of passes, do you see it? I just posted my problems, I inserted the values shown in a YouTube video for FlatCAM and my traces get "wiped out" too. If it weren't for that I'm "sort of" happy with results for my first day but a PCB with no conducting traces is kinda useless! Will be watching the replies you get closely...