GRBL 1.1f Laser power change with speed change

I keep reading that LB does not support MIN power for GRBL controllers because they cannot vary the power with a speed change (causing burnt corners). However, I read on the LB Common Grbl Setups page, Grbl Flavors, 3rd paragraph, that 1.1f does indeed support variable power. My machine has the Woodpecker board running GRBL 1.1f, so does it or not support the MIN power feature. If not, can you provide a reason?

I think you’re munging a few concepts. Variable power is supported by GRBL. That is handled by the firmware and happens as long as you don’t use “Constant Power Mode” and using the right device profile.

LightBurn does not have a Min power field for most operations. The except being grayscale images where Min power is supported.

My query is directed more at corner burns when making direction changes. I thought I read LB (GRBL) does not reduce power in sharp turns. I am away from home, so I cannot test anything right now.

Not sure what you read but this could be a matter of semantics. LightBurn itself does not reduce power in turns. However, it supports the command used (M4) that will instruct GRBL to use variable power to reduce power for acceleration/deceleration.

So if your basic concern is whether or not LightBurn allows for variable power around corners the answer is yes. Just don’t use Constant Power mode and make sure you’re using “GRBL” device profile and not GRBL-M3 or other variant.

Everything you say is correct. I found the answers buried in the Wiki for GRBL. M3 is constant power, M4 is variable power.

If you have a GRBL controller, you might find these links very interesting.

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