Slanted/Angled/Sloped Edges & Cutting Through Material

Procedure 1 (Mirror Alignment Troubleshooting)

1. Assure the alignment of the first 2 mirrors are correct then most importantly the 3rd mirror is shooting out of the laser in the center of the nozzle. By placing a piece of painters tape on the bottom of the nozzle and pressing lightly on the tape to create an outline of the nozzle, and its smaller opening (it will imprint a circle in a circle), assure the output from the pulse is centered. If the 3rd mirror is not aligned to the center, the laser can bounce off the nozzle and cause undesired results as shown below. 

2. After checking the mirror alignment is correct test it out by removing the nozzle of the laser head and doing 1 small/thin cut to see if the laser is still not cutting through the material at all corners or is still on a slant. If the laser is still not cutting through or is slanted proceed to the next procedure.

Procedure 2 (Laser & Table Alignment)

1. Acquire a gauge block or a reference block and check the flatness of the table in each of the (4) corners, to the flat area above the nozzle by jogging the Z axis to the height of the measuring object. Check the back right corner of the machine then the back left, after check the front left corner then the front right. As shown in Figure 1 below.

2. If only one of the corners have a significant gap measure the gap with a thickness gauge (as shown in Figure 2 below) or a piece of material to use as a shim or a washer to shim in further steps to compensate for the offset. If the table is relatively flat move onto Step 5.

3. Remove the honey comb table and unscrew the (2) bolts in each corner of the bed totaling (8) bolts as shown in Figure 3 below. 

4. Raise or remove the table and place a shim on the corner bracket that is offset, between its (2) bolts or place the  washers on the brackets bolt holes to compensate for the offset difference as shown in Figure 4 below. For example the thickness gauges offset in Figure 2 above measured 0.050" lower in one corner than the other corners, the acquired washer is 0.025" so placing 2 washers on top of each other underneath the black Z axis tables, bolt holes compensates that corners flatness offset.

5. Acquire a right angle/engineer’s square and place it on the machines table against the head of the laser and assure the head is square with the table. If the head is not square loosen the bolts indicated and position it perpendicular/square to the table then fasten the bolts, as shown in Figure 5 below.

Figure 5

6. Place a flat piece of material on the machine bed and hover over the material then activate the “Auto Focus” function which will raise the Z axis’s machine bed against the push probe then positioning the set focal height and Z axis home position.

7. Measure the distance between the material and the base of the nozzle as shown in Figure 6 below. It is recommended to use gauge blocks and/or a thickness/filler gauge for precision. The recommended offset is at 26.5 mm. Measure the offset and record the number to calibrate the Z axis’s positional settings.

1. If the measurement is less than 26.5 mm, record the difference measured and label it as (Z Axis Settings, Home Offset (mm), for use in further steps.
2. If the measurement is more than 26.5 mm, record the difference measured and label it as (Miscellaneous, Focal Distance) for use in further steps.

8. If Step 7 was not approximately 26.5 or you wish to adjust it slightly at your own discretion, Open the LightBurn software and connect to the machine either through Wi-Fi or USB connection and jog the machine to verify its connection.

9. Click on the “Edit” tab to expand its list then click on the “Machine Settings” to open the settings, if the settings are not displaying then click the “Load” button to access the machine settings as shown in Figure 7.

10. If Step 7.1 was true (less than 26.5 mm) then scroll down to the “Z Axis Settings” category and click on the value to the right of “Home Offset (mm)” and add the measured difference from 26.5 mm, which will only allow the table to lower with the Z Axis Settings, Home Offset from its default offset of “0” as shown in Figure 8 below.

11. If Step 7.2 was true (more than 26.5 mm) then scroll down to the “Miscellaneous” category and click on the value to the right of the “Focal Distance” and subtract the measured difference from 26.5 mm, which will allow the table to raise with the Z Axis Focal Offset from its original value as shown in Figure 9 below.

Figure 8	Figure 9

12. After changing the values in Step 10 or Step 11 click the “Write” button then carefully “Auto Focus” and the distance will accommodate to your set designations whether its to change the Z distance to de-focus/de-blur or fix the recommended offset.