LAF is short for look-ahead feed. It is an algorithm that tries to reach the maximum possible speed. This is done bij Looking to the future of the path that is to be executed. The algortihm will try to accelerate through, even over small pieces of lines (G1) generated by (3D) CAM software. If a curve is comming up, LAF will decellerate just in time, so that the MAX acceleration of the machine is not violated.
Thanks to the LAF, especially with the CAM G-Code the machine will reach a speed, close to the given FEED value.
Experience shows, that with LAF, it is possible, that the machining time is reduced by half compared to conventional CNC controls without LAF.
The minimum angle LAF in the setup of the software is a further optimization to get higher speeds.
It is the angle that line piecesare allowed to make without ramping down, lines with an angle lower than this value are considered straight. The value of the LAF minimum angle is dependent of the machine and G-code program..
A value of 3 degrees is usually OK for most machines. I recommend not to go above the value of 6 degrees, because then relatively high acceleration peeks may occur. Check bij homing a second time whether steploss occurs, if so, lower the LAF min. angle value.