Outline errors in g-code?!

Easel
1

I have problems with the outline in G-Code.

When I make a square of
x:0
y:0
width:100 mm
height:100 mm
bit size:6 mm

These are te results:

‘on path’ is correctly executed!
G1 X0.000 Y100.000 F1016.0
G1 X0.000 Y0.000 F1016.0
G1 X100.000 Y0.000 F1016.0
G1 X100.000 Y100.000 F1016.0

’inside’ is correctly executed!
G1 X3.000 Y97.000 F1016.0
G1 X3.000 Y3.000 F1016.0
G1 X97.000 Y3.000 F1016.0
G1 X97.000 Y97.000 F1016.0

’outline’ is wrong executed!
To many coordinates and the wrong coordinates… what is happening here?

G1 X100.609 Y-2.938 F1016.0
G1 X101.615 Y-2.529 F1016.0
G1 X102.408 Y-1.788 F1016.0
G1 X102.888 Y-0.815 F1016.0
G1 X102.987 Y-0.279 F1016.0
G1 X102.993 Y100.205 F1016.0
G1 X102.907 Y100.743 F1016.0
G1 X102.453 Y101.728 F1016.0
G1 X101.678 Y102.488 F1016.0
G1 X100.683 Y102.922 F1016.0
G1 X100.143 Y102.997 F1016.0
G1 X-0.340 Y102.981 F1016.0
G1 X-1.378 Y102.664 F1016.0
G1 X-1.838 Y102.371 F1016.0
G1 X-2.561 Y101.563 F1016.0
G1 X-2.949 Y100.549 F1016.0
G1 X-3.000 Y100.000 F1016.0
G1 X-2.962 Y-0.475 F1016.0
G1 X-2.599 Y-1.498 F1016.0
G1 X-2.241 Y-1.995 F1016.0
G1 X-1.384 Y-2.662 F1016.0
G1 X-0.347 Y-2.980 F1016.0
G1 X100.068 Y-2.999 F1016.0

Does anyone understand this, am I doing something wrong or is it an error of Easel?

Kind regards,
Eric

2

Hi @EricLugtigheid,

Regarding “too many” coordinates, With offset paths, Easel tries to keep the edge of the bit following the original path. To do this, the center of the bit sometimes follows a rounded path—like the center of a jar that’s rolling off the table:

As far as the “wrong” coordinates, the ideal X & Y values would be -3.000 and +103.000. Easel calculates coordinates roughly to the precision of the machine’s steppers, 0.025mm. It looks like the least precise edge here has a coordinate of 102.993, for an error of 0.007mm or about a third of a step. So I don’t think it will make a difference when carving.

3

Hi Rodovich,

Thanks for your reply and the nice gif!
I can imagine that some calculations are necessary but because the inside calculation is spot-on and because the perfect squareness of the object it could well do with only 4 vectors.
I once wrote an algorithm to calculate the outline which just offsets the vectors with half the bitsize with quit some mathematics. It was written in Flash, a long time ago, so you got to have flashplayer installed (Chrome?)

I put it online for you…Take a peek:
http://lugtigheid.nl/G41G42/G42.html

4

Hello there

Please forgive me if this is a stiupid question, but I have the same dilemma as EricLugtigheid.

I would like to cut out a square with the dim 100x100mm. The the part I am cutting out is used.

But if I use the outline, my square are smaller.

So do I have to use one of the other option (on path or inside) and add the width of my bit ?

Best regards
Flemming the newbe

5

@FlemmingChristensen Can you share your Easel project?
It could be that you need to calibrate your steps per mm.