How to Manage an Auto Focus Crash: MIRA

Applies to: MIRA 5, MIRA 7 and MIRA 9

This guide shows what to do when the laser head crashes into the bed, or into material on the bed, during auto focus. Check the points below, in order, after a crash.

An auto focus impact happens to the best of us. The auto focus pins are made of brass so that they bend before anything else can be seriously damaged. Most impacts happen because the auto focus pin missed the material. When you auto focus, make sure the brass pin always touches the material, not only the nozzle.

What you need

• Allen keys
• Cabinet key
• Spare auto focus pins
• 90 degree carpenter’s square (a 4” square is ideal)
• Painter’s tape

1. Lower the bed

Use a cabinet key to unlock and open the front access door. Find the black or white belt that runs left to right under the laser bed. Pull the belt to the right by hand to lower the bed and the material out of the way. Once the head is clear, remove the material and the honeycomb tray.

2. Check the nozzle

Make sure the nozzle is screwed tightly into the laser head. A loose nozzle can hit the material before the auto focus pin does and cause a crash.

3. Check the auto focus pin

Make sure the pin is not bent, is screwed in tightly and moves smoothly. Press the brass pin up: it should move freely up and down in its housing. If the pin is bent or sticks, replace it. See Replacing the Auto Focus Pin. A few spare pins are in the clear tote that came with your laser.

If the sensor looks dirty, clean it now with compressed air, a lens wipe or a cotton swab.

4. Check the auto focus sensor

Make sure nothing in the machine can collide with the laser head as it moves around the bed. Turn the laser on and let it reset fully, then move the laser head to where you can reach it easily. Press the brass auto focus pin up and down. The red light on the sensor should turn on and off.

If it does not, contact us before you auto focus again. In the meantime, you can still use the laser by focusing manually with the manual focus gauge.

5. Check that the laser head is square

The crash has likely knocked the laser head out of square, and that needs correcting. Follow Squaring the Laser Head: MIRA. Do this on the blades, not on the honeycomb. A 4” 90 degree carpenter’s square is the best tool, though the pie wheel that came with your laser works in a pinch. The laser head must be as square as possible for the machine to perform at its full potential.

6. Check the Mirror 3 alignment

After you have corrected the squareness of the laser head, inspect the Mirror 3 alignment. Watch the MIRA Mirror 3 alignment video.

7. Run a 5 point test

Finish with a 5 point test, to confirm that the alignment lets the beam pass through the nozzle properly. Follow 5 Point Test: MIRA.