To deep cut

Hello all forum members

Is there anyone that can help me with my problem

When I set the material to 6 mm,
it cuts deeper than 6 mm

How do I set it so that it only cuts just below the material

Have you calibrated your Z axis?

Hi Larry
Do you mean if I have the bit down on the top of the material ?


To get precise results from the movement on each axis you need to calibrate your machine. Basically what this means is that you have to adjust it so that when you tell it to go 6 mm, it actually goes 6 mm instead of say 8 or 5 mm. Check out this video.

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Sorry Larry
I have checked the video earlier,
But I didn’t get the hang of it

This is a fairly basic requirement for making accurate cuts. The software and hardware have to agree on the length of 6 mm and calibration is the way that you tell the hardware how far to move when you tell it to cut 6 mm.

Thank´s Larry

I´ll take a look again and se if I can understand some of it.

Repeat this for each axis:

Place a measuring device (ruler etc.) parallel to the axis.

Put a sharp pointed mill/bit in the router/spindle.

Jog the machine so that the pointer is exactly at 0 on the measuring device.

Jog the machine a long distance on the selected axis, for a 1000mm machine say 700 mm. (make sure you are at a position that your movement would not send the machine out of bounds)

Look to see where the point of the bit is on the measuring device. Say it is at 705 mm.

The percent error would be (700 - 705) / 700 = -0.00714 (or -0.714 percent error).

So, if your axis setting in grbl is 40 steps per mm
(-0.00714 * 40) + 40 = 39.714

Change the grbl setting to 39.714 steps per mm for the axis you are working on and repeat the process until you don’t have any errors when you move the machine a specific distance.

Then do the other axes.

Thank you Larry for the explaining

I´ll try it later on today when I get back from downtown

By the way, I’m not familiar with the word “Jog”
what is the meaning of it

It just means use the arrow keys to move your spindle to a new location.

ok Thank´s. (now I know what jog means)
By the way
I was out to the workshop and tested like he did on the video
I placed a ruler in front of the x-axis and moved the spindle 600 mm with the mouse
and it stoped exactly at the 600 mm on the ruler.
Then I did the same with the Y-axis
and I got the same results.
Then I put the bit on the top of the waste board and increased the spindle 50 mm
and I measured the hight and it was exactly 50 mm

Does this mean that I don´t need to corecct something ?

(sorry if I spell something wrong here, after all I´m a Swede :smiley: )

For the Z, it really helps to be as accurate as possible.
Do you have a dial indicator, or calipers?

Using measurement calipers, measure some stock, and then try to get it under the Z; like you said previously. Zero from your wasteboard surface and move the thickness of the stock.
The calipers are critical here. you cannot use a ruler.
You must have .1 mm accuracy.

Now I’m a little bit frustrated here
Earlier the bits went to deep
And now it´s not, I wonder what´s going on

It´s not cut that I have been taught
I set the depth of the material to 6.3 mm (I have zero the bit to the top of the material)
but the cuts still not go through the surface.
I have trimmed down the material to exactly 6.0 mm with my drum sander
And I have been using a 3 mm bit

I enclose a link to the sample I’m trying to cut

PLease give me a hint so I can start using my x-carve

What kind of bits are you using, and what stiffening mods have you made to your machine? Upcut bits tend to act like screws and pull large material up when it’s only edge clamped, causing the cut to be too deep. Downcut bits will do the opposite and push the material down/push the spindle up if the cut is aggressive, causing the cut to be too shallow.

The key for using either of those type of bits is to make sure there’s good clamping (double-sided tape in the middle of large pieces for upcut) and reducing your depth of cut and/or plunge speed. Stiffening mods help, but aren’t required if you’re patient.


I was using 2 Flute Straight bit
and I was putting a long piece of double-sided tape in the middle,
but it stlll don´t cut thru all the way
there was about approx. ½ mm left before cutting thru

I am running into this issue as well. My material is 0.210" thick, measured in multiple places. I am cutting through the material, set to 0.210". DoC set to .03" I have no problem slightly scoring the wasteboard on the final pass, but Easel is taking a full additional pass into the wasteboard.

In checking my steps for the Z axis, I used a 1/32" scale ruler. I set a point on my spindle mount at an inch line and raised 3 inches in easel. The movement measured exactly 3 inches. Even if it had been off by 1/32" I can’t understand that making the difference of a full additional pass over less than 1/4" of depth.

This starts on the first cut of the project and is consistent throughout.

I’m confused.