What to do with scrap Perspex?
If you've ever done any projects involving Perspex, no matter how careful you've been to maximise your usage, you'll always have at least some scrap Perspex left over. Harry Gowlett, a second year Secondary Design and Technology Education student at Nottingham Trent University, shares some excellent tips on how you might recycle your Perspex offcuts into useful items.
What to do with scrap Perspex?
When visiting schools, I am always amazed by the amount of scrap Perspex there is left over from projects, within design and technology (D&T) departments. I therefore thought to myself, “how could I use the ‘left over’ Perspex within one of my projects at university” and this is the result…
Kitronik kindly allowed me to collect as much scrap Perspex as I liked from their warehouse. Normally any scrap Perspex from Kitronik is collected over time and then sent away for recycling in large quantities. However, for my project I have looked at ways that scrap Perspex can be used on a smaller scale.
After collecting the scrap Perspex, I went straight into the workshop at Nottingham Trent (NTU), which has a wide range of different machinery. New for this academic year is a shredding machine. I simply fed all my scrap Perspex into the shredding machine and I ended up with lots of shredded Perspex which was lovely to pick up and reminded me of fish tank gravel.
I then experimented with two different ideas I had for using the shredded scrap Perspex.
The university has also invested in a sheet press heater, new this academic year. The sheet press heater is used to form shredded pieces of material into one sheet, similar to how Perspex is purchased new. I poured out my shredded Perspex onto the sheet press bed, ensuring it was evenly distributed. I then returned the sheet bed to the heater and heated up the shredded Perspex to 200oC. I also raised the sheet bed occasionally, ensuring there was enough pressure to form a flat sheet.
After checking the sheet every now and again, after about an hour, I took the sheet bed out of the heater and allowed it to cool. The result of the process of creating a shredded sheet of Perspex looks very aesthetically pleasing, especially as I mixed a range of colours. The new ‘reformed’ sheet of shredded acrylic can now be used in a similar way to brand new sheets. For example, as can be seen, it can be used on a laser cutter.
Another idea I trialled was forming the shredded Perspex in a mould, in an oven specifically used in the workshop. However, this proved very difficult! Perspex needs to be heated to a very high temperature in order to effectively melt and form together. I created a small MDF mould for some acrylic and it took a great deal of time to melt and form together. James Burkill (senior technician at NTU) had more success forming the shredded Perspex in a cake tin, but this did take a great deal of time. Overall a lot of time and and a very high temperature is needed in order to form the shredded acrylic together in a mould.
I tried to create a large mould for my project to form a shredded Perspex seat top for a stool I made. Due to the size of the mould this proved unsuccessful, so I decided to create a casing for the shredded acrylic instead using a clear piece of Perspex. The seat top looked very effective!
Perspex isn't the only plastic that can be shredded, most plastics can be shredded and made into reformed sheets or heated into moulds too!
Thanks to Kitronik for allowing me to use their scrap Perspex. Also, thanks to James Burkill (senior technician at NTU) for all his help with the project!
This post has been written by Harry Gowlett, a second year Secondary Design and Technology Education student at Nottingham Trent University. To see more of Harry’s work, follow his twitter: @HGowlett_DT.