BEAM-E Lens Removal & Cleaning
Your BEAM-E Laser Cutter focuses the laser beam from the glass CO2 tube using a focusing lens. This is situated in the moving head of the laser cutter, below a mirror angled at 45 degrees, to point the laser beam downwards towards the workpiece.
The laser head moves the focus lens and mirror 3 around the bed, reflecting and focusing the laser beam onto the workpiece.
You can move the laser head manually with the arrow keys on the controller keypad.
With the machine turned off the stepper motors that control the gantry (Y axis) and laser head (X axis) are free and you can slowly and carefully move the head and gantry by hand if needed.
You can remove the lens housing by turning the knurled/ridged collar, this will allow the lens housing, which is a tube that tapers to a cone, to drop down.
Turn this collar anti-clockwise to loosen it. The air assistance hose should carefully be removed from the spigot attachment if you need to move the tube/cone away from the machine work area.
The retaining ring at the top of the tube holds the lens in its place. This can be unscrewed by hand, turning it anti-clockwise to loosen and remove it.
The lens sits upon a lip within this assembly. The lens is made from Zinc Selenide with an anti-reflective coating.
You can clean it using a lens cleaning cloth and isopropyl alcohol or lens cleaner solution.
The lens is very small in the BEAM-E with a diameter of just 12mm. It has a curved upper and a flatter bottom part. It is a plano-convex lens, meaning it focuses the beam below the flat bottom part at 50.8mm or 2inches below its base.
The lens is a very important part of the laser cutter and should be checked regularly for dirt or damage.
When you replace the lens inside the assembly, make sure it is absolutely flat to the internal lip, with the curved side facing upwards.
Carefully replace the retaining ring with your fingers. Do not over tighten the ring.
Replace the assembly into the ridge collar and turn the collar clockwise to tighten.
It doesn't matter exactly where you replace this assembly below mirror 3. However you may need to recalibrate the camera on your BEAM-E after removal.