Calibrating the Backgauge – Pathfinder v2

1. Login to Pathfinder as Administrator

Figure 1 – Login as Administrator

1. Click Tools button at the top (displayed with red arrow)

Figure 2 – Select Tools Screen

1. Record your ‘122 Home Position’ and ‘131 Encoder Resolution’ parameters.

Figure 3 – Record Parameters

1. Reference your Backgauge by clicking Reference Machine on the left hand side.
2. The ‘Reference Backgauge’ button is shown in the picture below. Hold this button down, the backgauge will move backward to the home switch, stop, and move forward a small amount. You should see a message saying “All Machine Axes Are Referenced” in the white area on the right side, confirming that the machine is referenced. If you do not see this message, reference the backgauge again until you do see it.

Figure 4 – Reference Backgauge

1. Now that your Backgauge is positioned slightly in front of the home switch, note what your ‘X’ value reads for Backgauge Position. Record this as your “Expected Length 1”.

Figure 5 – Record Expected Length 1

1. Measure where you Backgauge is at physically with calipers (or tape measure), as your “Actual Measured Length 1”. Note that you are measuring where the metal would be placed in the ‘back’ location of your Backgauge.
2. If these values are not equal, or close to equal, your ‘122 Home Position’ parameter needs to be adjusted. If they are equal, or close to, your Home Position is set correctly. Skip steps 9-13.
3. To adjust the ‘122 Home Position’ parameter, click Machine Parameters on the left hand side and then Backgauge.

Figure 6 – Select Machine Parameters/Backgauge

1. Find your ‘122 Home Position’ Parameter and change this value by the amount that it is off. For example, say your Actual Measured Length 1 is 38.00”, your Expected Length 1 is 38.25”, and your Home Position is set for 39.00”.

• Subtract 38.25” – 38.00” to get 0.25”.
• Change your Home Position by 0.25”.
• 00” – 0.25” = 38.75”.
• New ‘122 Home Position’ of 38.75”.

1. Input your New ‘122 Home Position’ value of 38.75” and press Enter.
2. Reference your Backgauge again (steps 4-5) by clicking Reference Machine on the left hand side.
3. Go back to Step 6 and record a new Actual Measured Length 1 and Expected Value 1. These should now be equal or close to equal. If they are not, repeat this process until they are.
4. At this point, you have values for Actual Measured Length 1 and Expected Length 1 for a specific physical location of the Backgauge. To determine if the Encoder Resolution needs to be corrected, you need another physical location.
5. Go to the One-Step Operation Mode by clicking the ‘1’ button at the top shown here: . You will see the screen below.

Figure 7 – One-Step Operation Mode

1. For ‘Backgauge Position’, put in 1.00” so we can use the full length of the machine for the calibration. Using the full travel of the Backgauge will ensure our Resolution is most correct.
2. Find the ‘X’ value for Backgauge Position in the bottom left hand corner. This is going to be your “Expected Length 2” value.

Figure 8 – Finding Expected Length 2

1. Measure the Backgauge position with your calipers (or tape measure) again, record this as your “Actual Measured Length 2” value.
2. You now have the values needed to calculate a new ‘131 Encoder Resolution’ value. Use the following equation:

1. Enter your New Resolution value into the ‘131 Encoder Resolution’ parameter in your Backgauge Parameters.
2. Reference your Backgauge again (steps 4-5) by clicking Reference Machine on the left hand side.
3. Test some different physical locations on your machine and confirm that the ‘X’ Backgauge Position values equal the lengths you measure.

• If they do not, repeat this process until it does.