I am cutting some parts from wood veneer with 10mm radius curves created and imported as a DXF file.
I know that curves in this format get converted to short linear segments. My question, is there a parameter to slightly lengthen the “laser on” time for each of these segments (fraction of a mm)?
These images show the effect, seen as stitching along the curves where the laser does not completely connect with the previous cut. I assume that some amount of overscan which would extend the cuts slightly could eliminate the problem.
If I add more passes, these artifacts eventually get burned away but that makes for a lot of extra laser time.
Two tabs can be seen (12 & 6 o’clock in lower photo)
Thanks!
Having said that, it almost looks like you might be dealing with some backlash in your movement such that the ends aren’t lining up. Can’t quite tell from the pictures but something to take a look at.
Try increasing the Min Power setting in the cut layer to increase the power applied at low speeds.
As the laser head slows down at the junction of two lines, the power decreases from the Max Power level and, if the Min Power is too low, the beam stops burning through the material.
This is absolutely true for DSP controllers. However, note that @brewster is on a grbl board where min power won’t be an option (other than for grayscale).
I noticed that there is no “min power” option for my cut settings, but the “cut through” & “over cut” settings look like the ticket. I’ll also check and maybe tighten up the belts if they seem a bit slack.
The top photo shows some wood grains that have not been completely cut (added another pass to correct). The lower photo shoes with added passes for a cut through but the “stubs” are still visible.
Did a run through on all the mechanical connections, everything was right and tight.
Will try again with some of the cut settings changed once I get the unit fully functional again.
