One of the first questions asked when we tell people about how we print onto recycled raw materials is:
Where do you get the materials from?
And of course, the short answer to that is that we aren’t going to tell you EXACTLY where we get them from, because that would give away one of our trade secrets! But we WILL tell you a bit more about the various recycled raw materials that we use, and what the were in a previous life…
“Mild” steel is sometimes known as “low carbon” steel – we’re sure you can guess why! It has a lower carbon content than other types of steel, and lower amounts of other elements like chromium and molybdenum. These are used to harden and rust-proof steel, but they’re expensive. Mild steel is easier to bend and weld, and cheaper to buy. It’s often used in applications where it’s going to be shaped or welded into something and then painted or coated so it can’t rust – a lot of ours comes from the offcuts from making lockers, bike sheds and furniture.
Galvanised mild steel is the same as above, but rust-proofed by coating with zinc. “Galv” has a distinctive pattern on its surface as a result. While it will inhibit rust for quite a long time, prolonged exposure to the elements will cause it to break down. We use small amounts of “galv” but the coating is quite resistant to print, so it takes more work to print a sheet of it than it does to print on plain mild steel. Ours also comes from offcuts from office furniture manufacture.
Plywood is simply a multi-layer sandwich of thin sheets of wood glued together with the grain at right angles. This makes a sheet of plywood much stronger than a single sheet of the same wood of the same thickness. Softwood plywood (which is the sort we tend to get pieces of) is used for building applications such as walls, floors and ceilings, fences and packing crates.
Chipboard is also known as particleboard and is made from mixing wood particles or flakes with a resin and setting it into flat sheets. Chipboard itself is a good way of using wood that isn’t suitable for use as planks or flat sheets, so in a sense we recycle it for a second time. Chipboard isn’t as strong as plywood or MDF, or as water resistant, but as a result it’s cheaper. Our main source is pallet tops – sheets of chipboard strapped to the tops of pallets of paper.
MDF is short for ‘medium density fibreboard’, which is a manufactured wood like chipboard and plywood. MDF is made by shredding wood and sometimes other material like recycled paper down to the basic fibres which is then glued together with a resin. MDF is tough and flexible, but susceptible to moisture, and best practice to to seal cut edges – we use a clear lacquer to do this. It’s quite popular for school and DIY projects, because it stays flat, doesn’t contain knots and is easy to cut.