[Fraesi1]

Hi everyone,

I'm very new to CNC (I started with a Bamboo Lab P1S 4 month ago, around Christmas I stumbled upon hobby CNC machines - and now I'm building one... :-) ) One thing I want to use it for, is to cut small wooden boards to precise squares, like a small format saw. The planned procedure:

* Create a list of boards needed
* Feed this list to the software I have just started and get G-Code back (if the software can fit all boards on the original piece)
* Put my board to a marked default position (tape/superglue method for now, suction later)
* Start the Code
* CNC machine should home its self, get tool length automatically and go to default position
* Start cutting
* Take out cut boards and be happy about straight boards with exact dimensions

Here is what i have: This is my input text file for a dice, 2 boards 10x10 cm, 2 boards 8x10 cm, 2 boards 8x8 cm. So you have to type all dimensions as text, but no drawing at all. All that is needed are the counts of boards and their dimensions (and base settings for the machine of course):

M 90.0x60.0 10 // Material dimensions x,y [cm] thickness [mm]
D 0.6 // Cutter diameter [mm]
V 500 // Feed rate [mm/min]
T 2.5 // Depth increments [mm]
A 20 // (Minimum) distance [mm]

2x 10x10
2x 8x10
2x 8x8


This is the generated G-Code, from my program:

G17 ; xy plane
G21 ; mm
G90 ; absolute pos
M03 ; spindle on

G00 Z5.0 ; Work piece 1 100.0x100.0
G00 X0 Y0 ;
G00 Z0.0 F50.0;

G01 X100.0 Y0 Z1.1 F500.0 ;
G01 X100.0 Y100.0 ;
G01 X0 Y100.0 ;
G01 X0 Y0 ;
G01 X100.0 Y0 ;
...

G00 Z0.0
G00 X0.0 Y0.0
M05 ; spindle off
M00 ; end

Yesterday the shipment with the (closed loop) stepper motors and the Arduino has arrived, so i could wire everything together, could install a CAM Software and was able to run my G-Code (as there is no CNC frame for now, all motors on my desk happily moved in a concert :-) ) So I have no clue, if this would have worked, but it looked not too wrong in Estlcam...

So at this point I have two main questions before i put more work in (for now its only a prove of concept), while I plan my CNC or wait for parts):

Is this something that is already there and just have not found it?
Is this doable at all, or do i overlook a big problem?

Thank You
and
Best Regards
Fräsi

P.S.: there are a few more things you should later be able to do with a board. E.g. for one 10x10 board:

1x 10x10
/ ab
# C(4.0, 4.0) C(2.0, 2.0)
| 8 A(5.4,4.3)

/ ab
Needs the use of a normal cutter and a 90° router to be able to get 3 straight 90° edges as one mitered one (at edge ab between corners A and B)

# C(4.0, 4.0) C(2.0, 2.0)
Route a pocked 2x2 from corner point C (lower right corner)

| 8 A(5.4,4.3)
Drills a hole with 8mm 5.4cm right to top left corner and 4.3cm lower.

[Fraesi1]

So, I sat down a bit more and worked on it and now it seems - for straight edges only - to create something that could work and give correct boards. You can see the example from my first post in the attached image (the 6 sides for the cube). The only changes I did to config file since then, are that there are now more general settings like spindle speed etc.. Also In the settings I have now set, to create the boards 1mm bigger than given and only after the last run i cut all "layers" with full depth to the correct size at once (If this is needed, I don't know, but i have seen this in multiple videos I watched... So I guess I have to wait for my router to get ready :-). This is why the lower border is doubled.

[Fraesi1]

As this seems to be a "bit specific" requirement I will conclude this here, but as I myself don't like to not know the end of a thread I find a long time later, here a short conclusion: It's working fine now. The G-Code is generated and as I - thankfully - found the nice simulation software CAMotics this morning I was able to simulate the results (see second image). As the finished pieces in CAMotics can be exported into stl, I could also verify the dimensions in blender (Img. 1).

As I could "reverse engineer" the project files of CAMotics (it's json...) - I now get a simulation with the display of the raw material, the final boards and the tool path for every generated G-Code. This is probably very useful later when I really want to use this for creating boxes, drawers, etc.

I'm quite sure there needs to be done a bit work then (the pockets are probably supposed to clear out completely and not let left a small piece to get shooten out? Also there seems to be no drill command in grbl G-Code? So I just wrote a simple helix interpolation instead to be able to make round pockets - not sure this will be applicable as is...). But for this I have to wait for my own CNC for testing...

This is the full code for the 6 boards with all the holes (all these holes are the reason its a bit longer, config is now in a different config file, but can be overwritten here):

M 300.0x500.0 10
1x 10x10
# A(4,4) A(6,6)
1x 10x10
| 2 A(2.5,2.5)
| 2 A(2.5,5)
| 2 B(2.5,2.5)
| 2 C(2.5,2.5)
| 2 C(2.5,5)
| 2 D(2.5,2.5)
1x 8x10
| 2 A(1.5,2.5)
| 2 C(1.5,2.5)
| 2 A(4,5)
1x 8x10
| 2 A(1.5,2.5)
| 2 B(1.5,2.5)
| 2 C(1.5,2.5)
| 2 D(1.5,2.5)
1x 8x8
| 2 A(1.5,1.5)
| 2 C(1.5,1.5)
1x 8x8
| 2 A(1.5,1.5)
| 2 B(1.5,1.5)
| 2 C(1.5,1.5)
| 2 D(1.5,1.5)
# A(3,3) A(5,5)