Is there a setting to reduce the speed when cutting diagonally?

Is there a setting to reduce the speed when cutting diagonally?

I’m using xTool D1 Pro 40W.
With the same settings, I can cut vertically and horizontally perfectly, but I can’t cut diagonally.

I think the reason is that the diagonal movement speed is faster than the vertical or horizontal movement speed.
Maximum √2?

I don’t have any experience of your machine but the controller should handle all of the calculations necessary to give the programmed speed irrespective of direction. For example: if it’s cutting at 45° each of the two axes should be travelling at 70.7% of the programmed speed. Perhaps someone else that has experience with the same machine might be able to shed some light on what’s going on.

We’ll have to hear from others… but as far as I know you set your speed by the axes. Didn’t think any of these were that smart.

I looked back at my video of speed testing, but there wasn’t anything using anything other than 90 deg multiples.

:smile_cat:

If you think about it the controller has to calculate and adjust the speed of both axes otherwise the machine could only do horizontal, vertical and 45°. Any other linear angle or curve would not be possible otherwise!

I understand what you are saying and don’t disagree, but I don’t remember seeing anything like that in the grbl code I had gone through… Doesn’t mean it’s not there, but I just don’t remember seeing it.

I don’t know how it’s handled, you’d assume a set speed would be surface speed no matter what direction it goes or what is moving. I’d also expect this from any kind of milling machine.

I’m hoping someone who knows will pop up… but yes, I would have to agree…

I think @ednisley has measured this, if I’m not mistaken… maybe he can drop some results on us…

:smile_cat:

3 points on this:

  1. xTool machines allow no configuration ability so this is somewhat of a moot point
  2. max speed is defined on a per axis basis. However…
  3. linear feed rate should indeed be properly interpreted based on requested speed settings irrespective of max speed settings per axis. Meaning 100 mm/min should measure 100 mm/min irrespective of direction along axis or diagonal but cannot exceed the maximum speed setting on a per axis basis.
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In general, that’s not the case, because the controller computes the axis movements to maintain the speed set by the LightBurn layer at that value regardless of the motion direction.

However, if you set a layer speed higher than one axis can provide, the controller will decrease the actual speed so the axis can keep up. Because the other axis can run faster, the laser will move faster when the motion points along that axis.

Which means setting a layer speed higher than the maximum speed for both axes will work, as long as the motion direction keeps both axes below their limits. This is a common trick used by laser sellers, who will claim an “up to” speed with both axes running flat out at their maximum pace, with Pythagoras supplying a higher speed along the diagonal.

If both axes have the same maximum speed, then any layer speed up to that limit will be constant regardless of the direction. Setting a layer speed higher than that limit means the actual speed will vary based on the motion direction, exactly what nobody wants.

This is, however, an xTool laser where any settings that are not mandatory are prohibited and the firmware need not do what anybody expects, so pretty nearly anything is possible.

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Thanks everyone.

LightBurn doesn’t seem to have a corresponding setting.

xTool D1 Pro firmware doesn’t seem to let you adjust the speed. (Maybe it’s a Marlin variation?)
I need to find a setting that lets me cut at 45°.
(Vertical and horizontal are overkill though)

Is it possible to test 45° with the “material test”?

LightBurn sets the “feedrate” and the controller coordinates the axis speeds to ensure the laser moves at that speed regardless of the direction. If the LightBurn speed would exceed an axis limit, then the controller will reduce the feedrate so that the slowest axis runs at its maximum speed.

So there is no LightBurn “setting” other than the layer speed, because the controller does its best to make that speed happen.