We have an HPC 3020 laser cutter, which has a cutting workspace of about 30x20cm. It can be used for cutting a variety of wooden or plastic material, and is available for NSME/Northackton members to use, if they have been trained to use it. This is due to the number of subtle but dangerous risks in using the laser cutter, both to the user and the equipment. There is also a cost for using the laser cutter, calculated in terms of minutes of actual lasing time. This is due to the laser light source having a limited lifespan, and a high cost, and we want to have the money saved to buy a new one by the time it blows.
Most hackspaces have some element of training. We’re no exception. Only trained users may operate the laser cutter. This is mainly to protect the equipment from you rather than the other way round. There’s hopefully enough safety interlocks to prevent you inadvertently blinding yourself but the same can’t be said of setting fire to the machine.
There’s a charge of £10 for the training, which is to ensure you’re paying attention! Training is performed with the laser cutter, one on one, and will follow the example of other UK spaces. An example cut will be demonstrated, or you can bring a small design to cut.
- Don’t touch the cooling system: overheating or rapid cooling can damage the laser.
- Never leave the laser cutter unattended while cutting: your material may ignite, and an unchecked fire in the laser cutter could be both dangerous and costly. We’ve also seen mirrors go out of alignment and cut into the cables.
- In case of fire: use the CO2 extinguisher by the laser cutter first. Do not use the powder extinguisher unless you feel that you can’t control the fire. Put it in the logbook: tiny flames while cutting are normal; anything more must be reported.
- Never cut PVC or chlorinated plastic: you should always know what material you are cutting, and chlorinated plastics should be avoided because they release chlorine gas when cut.
- You can’t cut metal in the laser cutter: if you wish to mark the metal, please use Thermark/Cermark, or use anodised aluminium.
- You must not let the coolant get too hot – obviously, it doesn’t cool the cutter if it’s not cool. There’s a temperature probe on the cutter, don’t start a cut if the temperature is over 25C [to review]. This is low, currently there isn’t much thermal capacity in the system, this temperature will increase more quickly than you might think during some continuous cutting.
Some of this text is from the London Hackspace guidance and reference, which you should also read.
The capital cost of the laser was funded by Northackton member pledges along with an extremely generous matching donation from Martin Raynsford. In order to build up a fund for anticipated running costs (primarily a new tube when needed) usage is charged at £1 per ten minutes, or £6 a hour. This is nice round figure easily divisible into 10 minute chunks and seems to be in line with other hackspaces.
You must log your usage, which is time that the laser cutter is actually cutting. This allows us to measure how the cutter is aging.
For reference, the workable bed size is 275 x 217 mm and the largest possible piece which can be fitted in the recess is 326 x 260mm.
- 3mm ply sheet (~200x300mm) – £1
- 1.5mm ply sheet (~200x300mm) – £2
- Posh acrylic – (3mm, 5mm) offcuts from Hobarts (~300x150mm) – £2/sheet
- Random rougher acrylic offcuts (5mm, 6mm) acquired from Hamar – £1/sheet
- Rubber – a single sheet (~A4) available for now – £5
Once we know what we use lots of we’ll organise another bulk order. All the above material is laser safe. Other materials should be subjected to a chlorine test prior to use. It should be possible to cut card (corrugated doesn’t work so well), Depron, balsa, etc. but no metals. You are not obliged to use the hackspace-provided material – you can buy your own, but either buy from merchants listed in the reference material, or check with others.