Laser cutter
Introduction
This tool cuts sheet material such as card, acrylic and wood. At a reduced power rating, it will mark the surface without cutting all the way through. The laser cutter focusses a point of high-energy light into an area just a fraction of a millimetre across, and it instantly vapourises the material that it touches.
This information sheet does not describe how to create a computer file containing the shape to be cut.
The maximum size of material is 680mm by 500mm. That's a little larger than A2 size. Maximum thickness depends on the type of material and it reduces as the laser tube ages. 3mm plywood, 3mm MDF and 5mm acrylic are about OK.
Model
- KH-7050-B (aka KH7050 and possibly KH750). Some people refer to this as a redsail x700 clone
- Some good information from another maker club [[1]]
Chiller
An ATC KTD2460
We can't find a manual but the KT series on https://www.app-therm.com/downloads/ may be a useful reference.
The company were kind enough to share the electrical diagram they found. Thanks Phil!
File:KTD2460 electrical drawing.ppt
Refrigerant
400g of 134A
Photos
Safety
Two things to remember: Don't use it with plastic compounds containing chlorine (PVC, poly-vinyl-chloride for instance), and don't ever look at the laser beam when it's cutting.
There are protective glasses allowing you to glance at the beam while cutting, but these are not recommended for continuous viewing
Hazards include:
- Chlorine gas fumes when cutting prohibited materials
- Eye damage from looking at the light beam
- Material catching fire when cutting too slowly
- The mechanism crashing into something on the cutting table that's too high
Materials
- Can engrave
- Wood, Jade, Acrylic, Glass, Ceramic, Delrin, Cloth, Leather, Marble, Matte Board, Melamine, Paper, Mylar, Press Board, Rubber, Wood Veneer, Fiberglass, Painted Metals, Tile, Plastic, Cork, Corian
- Can cut
- Wood, Acrylic (up to 10mm thick), Delrin, Cloth, Leather, Matte Board, Melamine, Paper, Mylar, Press Board, Rubber, Wood Veneer, Fiberglass, Cork, Corian
- Can engrave when treated with specialist coatings
- Anodized Aluminum, Ceramics, Coated Metals
- Cannot Cut
- ABS - just melts and potentially releases cyanide
- Metals -Although you can use Metal Marking Spray e.g.
https://www.epiloglaser.com/how-it-works/applications/co2-metal-marking-spray/
- Carbon fibers (Carbon)
- Polyvinyl chloride (PVC)
- Polyvinyl butyrale (PVB)
- Polytetrafluoroethylenes (PTFE /Teflon)
- Any material that contains halogens (fluorine, chlorine, bromine, iodine and astatine), epoxy or phenolic resins
- Some woods are treated with fire retardant that may contain bromine
Some more information on the Reading Hackspace site, ATX Hackspace and cutlasercut.com
Instructions
tl;dr
- The software is on the windows 'lasercutterpc'
- Ruida RDWorks (
https://www.thunderlaser.com/laser-downloadhttp://www.rd-acs.com/newsinfo/1078010.htmlhttps://www.rdacs.com/download?id=1&m=software&a=RDWorksV8&v=4
sends commands over the network and will do basic design BUT....
- Most people export from Fusion360/ Inkscape etc. into a .dxf format and then import that (or .ai files) into RDworks
- Suggestion is that you install RDworks and play. An improved English translation of the RDWorks 8 user manual can be found [here]
- Laser cutter induction document File:LaserSummaryGuide.pdf
Before use
Switch on the laser cutter using the illuminated green rocker switch on the right-hand side. Check that the cooling water reservoir is not empty and that the pump is running. Check for a gentle air blower at the cutting head.
Switch on the computer monitor. The computer itself is left normally running.
Preparation
Using the computer, keyboard and mouse, open the RDWorks programme. There are two versions. Version 8 is recommended. Use File > Import to read in a .dxf, or use File > Open to read a .rld
Select the shape that is to be cut, then allocate a colour from the strip of colours at the bottom of the window. Double click the colour as it appears in top right of screen, and set the power level and the speed appropriately. Cutting all the way through wood requires a high power level, cutting through card or plastic sheet can be done at a lower power level and a higher speed.
Optionally, text or patterns can be selected in a different colour, and the speed and power settings may be chosen for marking without cutting. Large areas or designs with half-tone regions may require the 'scan' setting to be used.
Open the cover on the laser cutter and position the material to be cut onto the honeycomb support. Use the arrow controls on the top panel of the laser cutter to move the cutter head to be above the material. Adjust the height of the honeycomb support using the push buttons on the right-hand side of the laser cutter, so that the head is exactly 20mm from the surface of the material. There's a plastic guide to help with the measurement.
Using other programs
How big can I cut?
There are two parts to the question, how big a sheet can I put in the machine, and then what's the biggest part I can cut?
1) The machine can take a sheet 740 x 600mm, but the laser can't reach all of that area.
2) The machine can cut in an area 680mm x 500mm (a shade larger than an A2 sheet of paper)
Using it
On the screen note the 'origin' mark, a small green square. Manually drive the cutter head to a position over the material where the origin should be.
The cutter head has a small red light beam that shows where the laser beam will cut. The accuracy of the red beam is affected every time the height is changed, so you may need to re-calibrate it.
Close the top cover. Back at the computer screen, click on the button 'Send to cutter' and the laser cutter should start to operate almost immediately. Sometimes there's an error message, in which case just repeat the click on the 'Send' button. If it still won't work after a few tries, switch off the laser cutter and switch it back on again.
At the end of the cutting process, the laser cutter emits three quiet beeps.
When finished
Clear up any cuttings from the honeycomb support. Switch off the laser cutter and the extractor fan. Exit from RDWorks, turn off the computer monitor leaving the computer switched on.
Examples and other lasercutting locations
Some examples of work and other locations for laser cutters here
Aligning the laser and maintenance tasks
Big enough for it's own page Laser_cutter_aligning