Our lovely friend Chris from Laser Cut Supplies has written a guest post for us to explain how he brings to life amazing designs for Under the Rowan Trees.
I’ve always been creative, and found my first love for computers 25 years ago. I started graphic and web design when I was 13. I’ve taught myself everything – never had any education in computers or design. I’ve always used technology and creativity to solve problems.
I moved to Leeds from Hull when I was 21, met a girl, fell in love and decided Leeds was my new home. 5 years later we have our first child. My partner is very meticulous with a keen eye for detail. For our son’s first birthday she bought boxes and balloons and stickers and made personalised favour boxes for the children. The comments she received were fantastic and as she enjoyed making them and so wanted to make a small business out of it. I worked out that the profit margin was tiny, and we couldn’t charge more for what is essentially a disposable item.
I had been looking for an excuse to buy a Silhouette Cameo craft cutter, and with a small bonus from work, this was the perfect excuse and opportunity to buy one knowing I could save money by making everything from scratch.
As time went on I brought many ideas to life, but eventually my tiny craft cutter was no longer cutting it (pardon the pun) and about a year ago during a stint of depression I decided that if I didn’t change anything, nothing would ever change. I decided to invest in a laser cutter. Secretly I’d been wanting one for years, but never had the guts to outlay such an expense. I took a risk and it paid off. I love experimenting and creating. It’s the perfect tool for me.
Laser cutting starts at the design stage.
When designing something for laser cutting, a few things need to be taken into consideration. Because a laser cutter burns the material, although not impossible, it’s very difficult to achieve shades. Any point on the material is either “burnt” or “not burnt”, so for simplicity let’s call this Black & White. All designs are created in blocks of black and white.
You also have a choice of cutting, engraving, or a combination of the two. When you decide to cut a section you need to think about whether or not that section is going to fall out of the design or not. You also need to think about how strong each section will be once cut. Because of the precision of the laser it’s easy to create objects so thin that they break very easily.
A lot of thought needs to go into the designs to ensure that they are both attractive and functional.
Once a design is created it needs to be exported to the laser.
A laser cutter is a type of CNC (Computer Numerical Control). CNCs don’t use pictures like a printer would, they use
vectors. A vector is two points with velocity. The machine uses two (sometimes 3) axis to move a laser beam along a vector. The laser works a lot like using a magnifying glass focusing the sun to burn things, except the focus has a much higher precision than a magnifying glass. If focused correctly it is precise to 0.01mm
Preparing a laser cutter for use is a much more complicated process than simply pressing print on a printer.
A laser is produced in a fragile glass tube – something to do with agitating co2 inside a chamber. I don’t really care for the science involved. The tube gets hot. very hot, and as such needs to be cooled. If the laser tube raises above 25C it will shatter. To keep it cool, water needs to be pumped through the tube all the time while operating. About 50 Litres of deionized water helps keep it cool for a few hours of use.
One the beam has been created, it needs to be redirected to the material, and it does this by being bounced off 3 carefully placed gold plated mirrors and then finally through a focusing lens. All these parts need to be cleaned on a regular basis using Isopropyl Alcohol. this removes all dust and grease and soot. If you were to leave the parts dirty they would heat up and eventually crack.
As we are burning the materials a lot of smoke is produced. This needs to be removed from the machine and the room. A simple air extractor does the job here. You know the saying “Where there is smoke, there is fire.”? That is very true here. A small flame is often created at the laser point which can damage the lens, or much worse cause fires. This needs to be extinguished, and we do that by focusing a jet of compressed air right at the point. This not only puts the flame out, but it reduces the heat of the smoke, and in turn reduces the extent of the burn to the material.
The laser usually cuts at around 2cm per second (which is pretty slow) and some cuts – depending on complexity – can take in excess of an hour to cut!
The materials that we use includes paper, card, mdf, spruce plywood, American walnut, cherry and acrylic. We are always exploring with new materials.
There are some materials that we can’t cut – anything that contains chlorine for one. This would produce chlorine gas and that’s probably the last thing you want to be inhaling. Other than the health issue, it would corrode the machine. Polyvinyl Chloride is hidden in a lot of things. A good example is LPs which sometimes get laser cut. This must be done with more advance machines and ventilation
Each material that we use has different settings, so it’s not a case of one size fits all, and as most of the materials we use are from nature, we often find imperfections and have to compensate for these.
I personally find acrylic the best material to work with; the engrave gives a good contrast, it cuts cleanly and it smells great. It can be filled with acrylic paint, and sanded easily.
Who knows what the future holds? Maybe a bigger laser and a workshop. I’m still testing the water but I’m confident that one day I’ll find my niche.
Laser Cut Supplies can be found on Facebook.