Laser Cutter Manual

Laser cutter one-page manual

The laser cutter is now at a level where it can be used by inducted members, but can be improved.

Required Software

To use the laser cutter you need to install VisiCut.

When you open VisiCut for the first time it will ask you where you are. Select Leeds Hackspace from the list.

Performing a cut

Prepare your work-piece in Illustrator, Inkscape, FreeCAD or similar that can export SVG, EPS or DXF files. Using Illustrator CC 2015? Use these settings when exporting your SVG files, or colours won't be saved properly.

Power on the Laser cutter prior to clicking execute in VisiCut. This starts the booting sequence and indicates to other members in the space that you intend on using the laser cutter.

From the File menu, select Import and load your SVG, EPS or DXF.

At this point you need to decide what kind of lasering you will be doing:

• Cut everything as lines, Dither everything or Solidly engrave everything, simply select “Cut Everything”, “Engrave (dithered)” or “Engrave (solid)”, Mark Shallow or Mark Deep as your mapping, check Speed and Power settings are accurate under “Laser Settings”, and click Execute.
• Do different things for different colours of shapes - Select Map by Color, and Select the type of cut/engrave per colour. Then click on each item that is coloured on the work area and check the “Laser Settings” tab to verify the settings are correct, then click Execute.
• Please note that we are still calibrating the machine for raster etching and this function is not yet available reliably.

Here is a test file to use during inductions and when calibrating materials: https://wiki.leedshackspace.org.uk/wiki/File:LASER_TEST_FILE_-_NO_RASTER.svg And here is a cute owl: https://wiki.leedshackspace.org.uk/wiki/File:Hsowl.svg

Place your workpiece on the cutting tray, take the ruler device and ensure it is flat against the side bar and the surface you wish to cut. If it is not, use the up/down switch to move the bed up/down. Note that if you have to do this, the panel may lock up, at which point you have to switch the cutter off and on again and click execute again in VisiCut before you can start cutting.

If you press the red button on the panel, you can get to the main menu, where you can select Run or Boundaries. Not a bad idea to use the boundaries function until you get a feel for where the origin is on the cutter.

Insert your member card and wait for the LED to turn green, then click “Run” and click again to select the only file on the cutter (the cutter only ever keeps the last file on it and deletes it on startup). You should be keeping a track of your usage at this point, time spent with your card in the slot is what is chargeable. It costs £1 per 10 minutes (£1 minimum charge).

Remove your card as soon as your cut is complete. Once you have finished cutting, power off the laser, then take the dustpan and brush and clean out under the cutting area.

Advanced Lasercutting

Cutting order: Because some materials (mainly ply) can be warped it is useful to set up your job in the following order: Engrave, Mark, Cut. Cutting out your piece should always be last, because if the material is warped or raised it will move up or down when cut out and this will affect the focus of the laser. You can change the order by selecting a process in the list and then clicking the up or down arrows on the right.

If you need to hold down the board you’re cutting there are some flat metal bars on the table beside the laser cutter. If you use them you must do a boundary check before cutting to make sure that the bars are outside your work area.

Using Mark

• Mark Shallow and Mark Deep are essentially exactly the same except for one very important difference - Mark Deep will not mark any line inside another, so if you have a circle inside a square it will only mark the square; if you Mark Deep a spiral it will only mark the outermost ring. There must be a reason for this but we haven’t been able to work it out yet.
• Using Mark on plywood, the settings become a bit less obvious. The reason for this is that the glue between the sheets that make up the ply is much harder to laser than the wood. So cutting through just the top layer is easy having a wide range of values between just cutting the wood and not quite cutting through the glue. Cutting through the top two layers is extremely difficult as the power required to cut through the first layer of glue is more than enough to cut through the wood layer below and most of the glue layer below that.

Cutting through only the top layer of plywood then allows you to do 'fake marquetry' by staining areas with different dyes, a technique that doesn't appear to have spread beyond Leeds Hackspace (see display cabinet at the front of the Hackspace for examples).

Artwork: Preparing the artwork for successful cutting is the most time-consuming part of the whole job. There are various problems that may arise:

Visicut can not deal with text as text. All text must be converted - to outlines for cutting and marking or to a bitmap format (png, jpg, etc.) for engraving.

Visicut can’t handle some forms of groups so it’s best to Ungroup everything before sending the image to the laser cutter.

Importing an SVG file made in Adobe Illustrator on a Mac will bring up a message in Visicut that the resolution has been changed from 90ppi to 72ppi. SVG is a vector format so is not resolution dependent and so this message can be ignored.

Illustrator can also create empty points that don’t connect to anything and so have no stroke or fill. Visicut does not like these at all, so it is a good idea to select everything and Clean Up (Object > Path > Clean Up).

Complex Images Using a vector image that was designed for print may not work in the laser cutter. Lots of lines close together (for shading or whatever) will darken a print image. On the laser cutter each cut heats up the ply/perspex/mdf around the cut, so if the next cut is close by it will cut deeper. Before long you will end up with charcoal. The laser cutter works best when doing simplified images - outlines and the essential basics. There are other ways to do shading that won’t destroy your piece: staining, painting, pyrography etc. This can be particularly annoying if you’re trying to Mark smallish text. One possible solution is to select every other letter (once they have been turned into outlines) and give them a different colour stroke. This way the material has time to cool down a bit before doing the adjacent letter and is less likely to cut too deeply.

If you do want to make a complex image it’s best to divide it up into several smaller parts. The easiest way to do this is to give a different stroke colour to different parts. When it comes to lasering, select By Stroke Colour and Visicut will list all the colours separately. You can then set them to be lasered as you want (remembering to leave Cut until last) and it will deal with them in that order.

This is very useful as damage limitation because the more complex an image, the higher the probability the laser will freeze on you. Once you have restarted the laser you can resend the image, leaving out the parts that it has already done. (hacky technique - if it freezes in the middle of a colour you can restart it and set it running with your card out of the machine. By doing this the laser won’t fire but it will go through the motions in exactly the same order, so when it gets near to the point that it previously froze put your card back in and the laser will come back on for the rest of the process.)

Debugging

A red light on the card reader interface means that either:

• The card reader board cannot reach the internet or
• the card is not registered/ its owner is not inducted for cutting.

If everything appears correct, but the laser is still not cutting:

• the lid may need to be re-seated or ensured it is pressed down or
• there may be a fault with the micro-switches on the lid or
• the panel to the underneath area may not have been put back properly after cleaning.

If you have any or repeated problems, please post with detail (software, hardware used, the file you were cutting, etc.) on the mailing list.