Reference Section > Touchcut G Code Reference > Notes on Using G-Codes:

TouchCut uses explicitly stated bevel angle and rotation angle codes; i.e. G1X100.A-45.R180., where A-45. specifies a -45 degree angle, and R180. specifies a rotation of 180 degrees. Be aware that the angles specified on a line of NC code indicate the state of the bevel at the time that the line is completed. In the example shown above the line previous may have had a bevel angle of zero degrees as shown below:

G1A0.R180.

G1X100.A-45.R180.

In this case the top line simply sets the bevel up with the desired angles so that when the bottom line is started the initial bevel angle is zero degrees. The bevel will then smoothly transition to 45 degrees while the bottom line is being cut.

The explicit rotation angle means that tangential following is not mandatory, and so a wider range of bevel geometry is possible; for example you can bevel a hole in thick plate so as to allow a pipe to pass through it on an angle. In this situation the bevel angle and the rotation angle will be constant throughout the cut.

The rotation angle is normal (Perpendicular) to the path such that if you are looking in the direction of the path the line defining the angle goes out to the left. The actual value is relative to the X and Y axes for the program. The figure below helps to clarify this.

The bevel torch angle can be positive or negative. As the bevel can only lean over in one direction, a negative bevel will result in the turret rotation angle being 180 degrees opposite than a positive bevel angle. You do not need to explicitly define the angle of the bevel turret rotation as this is interpreted in the touchcut software. You should only define the rotation and angle of the desired bevel cut. Below is an example the difference between a positive and negative bevel angle.

Below is an example of a 100mm diameter disk cut with a -45 degree bevel ('bottom bevel') from 10mm thick material.

G0X60.Y10.

G41

M30

G1A-45.R270. (set bevel up with desired angle and rotation)

G3X-10.Y-10.J-10.R360. (leadin with rotation finishing at 360 degrees)

G1R0. (set rotation angle to zero)

G2X-100.I-50.R-180. (first half of circle with rotation finishing at -180 degrees)

G1R180. (re-define rotation as 180 degrees)

G2X100.I50.R0. (second half of circle with rotation finishing at zero degrees)

G3X10.Y-10.I10.R90. (leadout with rotation finishing at 90 degrees)

In the example shown below a disk is being cut with a positive 45 degree bevel in 10mm material, but with a constant rotation angle, this results in a slanted profile. The main difference is that the rotation is specified at the beginning of the program, and stays constant because it is not specified again. In this case the circle has been split into four quadrants by the nesting software; this is a default action when tangent following is not used allowing greater control of the motion of the bevel.

G0X55.Y15.

G41

M30

G1A45.R0. (set bevel up with desired angle and rotation)

G3X-15.Y-15.J-15. (leadin)

G2X-50.Y-50.I-50. (first quarter of circle)

X-50.Y50.J50. (second quarter of circle)

X50.Y50.I50. (third quarter of circle)

X50.Y-50.J-50. (last quarter of circle)

G3X15.Y-15.I15. (leadout)

In the next example a rectangle is being cut with a varying angle on the long sides. These start at zero degrees, are 45 degrees at the middle of the line, and then transition back to zero by the end of the line.

G0Y-10.

G41

M30

G1R180. (set up bevel with 180 degrees rotation, no bevel angle specified so stays at zero)

Y10. (leadin)

X10.Y60.A45. (first half of first side with angle starting at zero (by default in this case) and finishing at 45 degrees)

X-10.Y60.A0. (second half of first side with angle starting at 45 (defined by the line above) and finishing at zero degrees)

G1X70.R0. (first short side of rectangle, rotation changes by 180 degrees so that bevel is ready for the next long side)

G41

G1X-10.Y-60.A45. (first half of third side with angle starting at zero (as defined three lines ago) and finishing at 45 degrees)

X10.Y-60.A0. (second half of third side with angle starting at 45 (defined by the line above) and finishing at zero degrees)

G1X-70. (last side)

X-5. (leadout)