Description of Issue

The “Please Load Bit Error” message occurs during homing when the machine is unable to verify the position of the bit tip.  The machine uses surfaces on the board tracking sensor (in the cutout of the strongback at the far left of the bit travel) and the swinging bit touch plate (at the far right of travel) to locate the position of the bit tip.  Failure to touch these surfaces results in this error.

Possible Causes

Causes include: no bit loaded into the machine, outdated firmware, incorrectly assembled bit, a malfunctioning bit plate, or a damaged board sensor.

Troubleshooting Steps

1. Verify that the correct bit is inserted, correctly assembled, and not loose.
2. Check that the Y/Z trucks are not loose.
3. Verify that the card has the latest firmware version.
4. Check for damage (usually a hole) on the board tracking sensor body.  The damage will be on the plastic bar of the board tracking sensor where the bit touches during homing at the far left of its travel.  If there is a hole, temporarily place a dime in the triangular recess of the board sensor over the hole and run the machine.  If this fixes the issue, add the Board Position Encoder Touch Plate (P1323) instead of the dime.
5. Run a project and watch if the bit plate is swinging out far enough for the bit to touch when it moves down.  The bit should touch on the flat surface of the plate and not on the edge.  If the plate is not swinging out far enough clean and lubricate the bit plate pivot post and spring.  Clean the plate mechanism with compressed air and spray WD40 on the spring.  Crank the head all the way up to the top and spry upward at the pivot shaft.  Actuate the bit plate several times to let the WD40 penetrate the mechanism.
6. Re-tension the Y belt.  A loose belt can decrease the force that the Y-truck uses to swing the bit plate out.
7. If the bit is touching the swinging bit plate on the flat surface and still getting the error, rotate the bit plate all the way and push down, slightly bending the plate down.  This will slightly bend the plate and increase the depth measurement.
8. If the bit is still not touching the bit plate then proceed to the “Bit Not Touching the Bit Plate” section.