Tools/laser/induction

Laser Cutter Notes.

ToDo: Split out the software from the machine induction. Provide notes on RDWorks vs Lightburn, introduction to both

Health & Safety – Risks.

1. Fire. The cutter works by burning material away. There will be fires. Not might, will.

Fires are caused by : Cutting too slowly through a material Multiple cutting passes – cut in a single pass or it can’t be cut Materials likely to burn – Cardboard and some acrylics. Debris in the bed of the machine Dirt on the tray of the machine

Materials : Black foam board always burns. Loose protective film under the job will burn and keep burning. Replace anything peeling with paper masking tape. Not plastic tape.

Always watch over the job while it is cutting. If you have to leave the room, hit Pause.

In case of a fire : Hit Pause to suspend the job. Does the fire go out ? Continue if safe to do so. If still burning, open the cover and see if you can blow it out. If not, remove the work piece and use the fire blanket. If the fire blanket is ineffective, escalate to the CO2 extinguisher, then the Powder. Powder extinguisher will wreck the machine - £6,000. Better than burning the building down though. Last resort – evacuate the building and sound the alarm.

2. Laser light. The main risk is direct eye contact. The top cover shields from exposure.

Do not attempt to look under the workpiece while cutting.

The top cover has interlocks to prevent the laser firing while open. If the laser will not fire, check the red lights on each interlock are lit. There are no interlocks on the side panels or the bed access panel.

The laser focusses at the lens. It is present but diffuse elsewhere in the bed.

3. Distractions. The room is a workspace, not a social space. Ask people to leave if they are causing a distraction to safe operation of the laser cutter.

4. Mechanical hazards. The arm can move at speed, causing injury if you have hands in the bed. There are no interlocks preventing the arm moving while the cover is open. The arm can be moved using either the front panel or the PC

Set the speed to 100mm/s for a sensible travel rate to position materials etc

The bed can also be moved (Z-axis) 5. Fumes Many materials will give off fumes during cutting. Eg, woodsmoke, powders from acrylic. Plastics can give of nasty fumes. ABS gives off very nasty fumes. Leather & rubber will smell very bad, and linger after cutting.

Open the window and doors if necessary. There is an extractor next to the heater in the electronics room.

6. Cutting Materials. PVC / Chlorides. These will generate Hydrochloric acid and damage the machine Fluorides (PTFE) These will generate Hydrofluoric acid and do real damage Unknown MDF May contain formaldehyde Do not cut any of these materials

MDF can be sourced from a reputable DIY store or buy ‘laser MDF’ for lower smoke.

7. Electricity. HV and LV power supplies located under the bed of the machine. Isolate before cleaning this area.

8. Water. The cooling system uses a water pump.

Any problems with this should be mopped up and reported on the forum.

Using the cutter.

1. Open and check the bed. Look for any loose material, cleaning issues Check the blocks is seated properly Check the head is above the level of the blocks

2. Power on the control panel. Beeps when ready. Check laser power dial is set to max.

3. Set the home position. Press ‘Home’ then select ‘X Y Reset’ and Enter System beeps when at 0,0

Panel notes – Enter == OK, Esc == Cancel

4. Seat the material. The cutter can work anywhere; close to 0,0 is more precise. The bed is not level. You may need packing. There is mesh available for very small jobs.

The head must be 6mm above the workpiece. Use the 6mm block to set the height. Adjust Z-Axis then test height – do not leave the block in place or you may damage the head by running it into the block.

Leave the cover open at this point.

5. Start the cooling pump. Switch on the unit next to the laser cutter. Beeps when switched on

6. Move to the PC. Start RDWorks or LightBurn and load the job.

Uses .dxf files, prefers v14.

Green dot is the laser position over the workpiece at start. This assumes ‘Current Position’ mode.

Use ‘Go Scale’ option to make the head describe a box round the size of the job on the workpiece. Set speed to 50mm/sec Adjust the scale if necessary. Do not use ‘Cut Scale’. It tries to cut around the job…

Config → System Settings can set the laser start position relative to the workpiece. This may have been set to something ‘unusual’ by another user.

Colours control different layers. Each layer has different settings for cut, etch etc

Modes : cut, scan, dot Cut is slower but more accurate Bitmaps are always scanned

Layer menu – can turn on or off Power – min / max Min power is 12%; Max power is 75%. Cutting, 65% / 75% then set speed to depth of cut required Sew compensation is an offset for the 0.2mm laser width Etching – use a faster speed and lower power.

Scan mode – X or Y swing. Makes lines in X or Y direction for the cut. Can make two passes to get a cross-hatch. Interval == gap between the lines

Use the Preview tool to check the job. There should be numbers showing job time etc. If not, something failed. Run the simulation to test the job Close the window when finished

Save often …

Check the job size on the rulers. Select the job and you can change the scale

Preferred colours are black, blue, red, green, yellow as they will import from the graphics package better.

Can auto-fit a number of copies on the workpiece. Bestrow will fit the max number of jobs to a set size of workpiece Virtual Array will fit a number of rows & columns with spacing

7. Turn on the laser power. Close the top cover. Switch on side of laser cutter. ‘Water error’ may be no cooling or interlocks are not engaged.

8. Run the job. Hit ‘Start’ on the PC Watch the job run. Do not wander off – fire hazard. Note the time for each cut from the front panel 20p per minute in the honesty box, or make a payment at the end of the month.

9. After cutting. Let the fumes clear for a while Retrieve the job Switch off the laser, cooling, front panel Clean up Gloves and wipes to clean the rails. Use the wire brush for baked on material on the rails Clean the bed as well – wipes, hoover, dustpan etc Close the top cover and make sure you have switched off

11. Pay up!