I am cutting a series of pieces that mostly consist of arch segments about 6’ long and 6" wide, with finger joints at the ends and notches in a few places along the edge.
Using ESTL to generate GCode, and I’ve confirmed that it outputs the same feedrate throughout the output.
The vast majority of the moves output by ESTL are G02 and G03, all with the same F parameter.
I’ve noticed that Marlin moves slow on the long segments, and speeds up tremendously on the short segments (the crinkly bits). Which is exactly the opposite of what seems to make sense.
In short, the speed is MUCH higher when it’s making several short moves, vs a long move.
I’d like speed to remain constant throughout the cut. Right now, my feedrate setting is sort of meaningless except as a general guideline.
I’ve messed around with Acceleration (M201) and Max (M203) on Marlin. So far, no luck. It feels like Marlin is making assumptions around 3D printing and final travel speeds that don’t apply to cutting wood. On the other hand, it is the preferred firmware for Lowrider2, so therefore it must be possible to make it DTRT.
Or, maybe there’s an explanation why CNC machines move much faster on intricate cuts than on the long ones?
Perhaps the results of the algorithm are more pronounced on very large moves?