The Precious Plasticaster

“The idea for the plasticaster came from a desire to change the perception of plastic as a cheap and easily discarded material.
By combining plastic with valued traditional materials like wood and metal to create a treasured object, it has been really rewarding to see people change their minds about plastic when they pick the guitar up and feel that it is unlike anything else.”

As part of a 2018 collaboration between Precious Plastic Monash and Monash Art Design & Architecture, the Precious Plasticaster is a handmade solid body electric guitar built by industrial design student Albert Lam as part of his final year studio project. The body is made from recycled polypropylene sourced from garden pots and plastic furniture, while the neck is a bolt-on one-piece maple. The hardware and electronics were commercially sourced. Various trims and details were also made from polypropylene and polyactic acid from discarded 3D printed waste.

The following are excepts from Albert’s accompanying book about the conception and building process of the Plasticaster.

Often thought of as cheap and discardable, the misconception of the easy disposability of plastic came about in the post-war period when there was huge consumer demand for products previously unavailable due to production and material limits.

Plastic was considered a cheap substitute and readily discarded because it was so lightweight compared to other valuable wartime materials like wood and metal. It was also cheap because it came from what was believed to be an inexhaustible supply of oil.

We now know this is not the case as, from 2017, there is only an estimated 50 years of oil production left worldwide. However, as environmental concerns continue to grow, the impact of wasteful plastic usage is gaining widespread awareness through economic incentives and personal attitudes. Acceptance of renewed materials is fast becoming a social norm now with recycled plastic being used in products made by the likes of adidas, Apple and LEGO.

In an industry dominated by tradition, anecdotal evidence and personal preferences, guitars that use recycled plastic are an uncommon sight that is usually limited to custom/single-run instruments or art pieces. However, the one purpose that unites these instruments is the human impact on the environment.

One example is the range of guitars made by industrial design student Jack Hyland of the Penny W. Stamps School Of Art & Design in Michigan. These use a similar manufacturing process to the Plasticaster though with different materials and the use of CNC, and are a response to changing consumer habits in regards plastic recycling.

On the other hand, guitar maker Simon Lee designed the Cyclotron range as a way to creatively explore the potential of modern materials without having to contribute to the destruction of endangered wood species.

The beginning of this project encouraged the experimentation and conceptualisation of different ways in which plastic could be used, not just in music but for other products as well. Many ideas were floated but after five weeks the concepts were narrowed down to the replacement of parts of musical instrument so that the instrument still retained its traditional identity. Yet, taking this idea further was to build a whole instrument out of plastic.

Initially, the idea of building a working instrument out of plastic was met with scepticism since it was unknown whether the plastic would be able to hold up to the stresses involved in making harmonic sounds, let alone sound pleasing to the ear. However, support for this idea grew as it would be a great way to showcase the capabilities and possibilities of Precious Plastic Monash.

Sketches helped to quickly visualise the overall look and feel of the guitar, based on the research conducted previously. Each component is equally important in function and aesthetics so it was crucial to find "matching looks".

As Precious Plastic Monash is still in its infancy, many of the techniques used to shape plastic are still being refined. Due to the limited time, product size, and expected amount of plastic required, there was little room for error which warranted extensive experimentation with the materials before commencement of the build.

Fortunately, PPM had access to a commercial oven which would enable the "baking" of plastic slabs. Test pieces were created although some failed due to inconsistent heat transfer, cooling, air bubbles, etc. but this was the point of experimenting first.

One of the setbacks from the testing was the inability to swirl the plastic consistently. Inspired by swirled paint jobs on existing guitars and wanting to achieve a marble-like appearance, a skewer was used to toy with the hot plastic while it was still a slurry but this resulted in the colours mixing to form a new undesired colour.

Unlike wood, plastic does not does not absorb linseed oil. Instead, the oil acts as a film on the surface which requires many coats to achieve glossiness. Other finishing liquids were tested but none were as convenient and easy to use.

The Plasticaster was expected to take at least a few weeks to complete, from the first cut to stringing up and playing. Preparations for the build began quite early with the templates laser cut and parts ordered. PP garden pots, a broken chair and lampshades were cleaned and cut up to prepare them for shredding into usable material. Discarded 3D prints made from PLA were also shredded to produce the knob and backplate.

The neck was the first major part of the build. Once the maple board was planed to the right thickness and the truss rod channel was routed, the shape was drawn and the holes were drilled. The laser cut template was then attached and the board was roughly cut into shape with a bandsaw.

Sanding and contouring was done with a handheld belt sander, dremel and by hand, stopping regularly to ensure the feel of the back of the neck was comfortable when held in the hand.

Work on other parts of the neck continued while contouring was perfected as much as possible. The fret markers were laser cut from the same PLA as the backplate, glued in, then sawed flush with the wood.

After filing the nut slot, the fretboard was ready to be radiused using sandpaper fitted to plywood bent into a 9.5" radius. Fretboards have a slight curve for better comfort when fretting, and it also allows the player to bend strings easier compared to a flat fretboard.

After radiusing and smoothing with wet sanding, the nut and fretwires were ready to be installed.

The fretwire pieces are an alloy of mostly nickel and copper, and were bent to shape before being pressed into the slots. Some frets required some wood glue for a better fit. The edges of the frets were then filed at a 30˚ angle for a more comfortable feel. More precise filing and crowning of the frets was done with a hobby file.

After the body was cut, the offcuts were cut and sanded to shape to cover the truss rod channel in what is commonly called a "skunk stripe". The skunk stripe was glued in, sawed and sanded flush with the contouring. This added level of detail further combines the tradition of wood with the modernity of plastic.

The body of the Plasticaster was made from polypropylene layered in a large custom-built aluminium tray and baked in the oven at 220˚C. The shredding of plastic was the first step, and although plenty of pots, a chair, and lampshades were shredded before beginning the baking, the amount of plastic required was underestimated - after the first night with almost all of the plastic stock melted, the slab only measured 30 mm high which was far below the target of 45 mm. A second day and night spent cleaning and shredding resulted in a slab approximately 470 x 330 x 50 mm and weighing a little more than 7kg.

The neck pocket and pickup cavity were routed before the slab was cut to shape expertly by the Mechanical Engineering Workshop. A flush-trim router bit was used to clean up the edges and cavities while a corner round bit rounded off the edges for a smoother feel when handling the body.

The body was then sanded down but, unsatisfied with the pitted surface, plastic "sawdust" was used to cover the holes and were melted into the surface with a heat gun. Larger shreds of plastic were also melted on top but this produced more holes than it covered.

The passages for the wires were then drilled and the surfaces were sanded flat again. Disappointingly, despite the best efforts for a completely flat surface, the sawdust filling had only partially worked. Further filling could have potentially yielded better results but time was limited by this point (Week 12) and the finishing was required. The body was intensively sanded to higher grits by hand in preparation for the oil coating.

Finishing the body began with the vinyl decals on the headstock (printed by stationery design studio From Yours Truly), followed by the application of linseed oil. Allowing plenty of time for drying, lightly rubbing with steel wool and recoating was key to a good gloss.

Once the final coat had dried on the neck, the frets were polished using steel wool with taped paper to prevent the fretboard from being scratched.

The electronics were the first to be assembled and placed in the body. By lining the cavities with aluminium foil in a process called shielding, the circuit becomes grounded and unwanted interference is eliminated. Of note is the treble bleed circuit which maintains the higher treble sounds as the volume is dialled down, and consists of a 150K resistor and 1nF capacitor arranged in parallel with the 250K volume potentiometer.

With a bright and snappy tone, the single humbucker, stripped controls and hardtail bridge is a no-frills approach to a guitar finished as black marble with a fractured vintage blonde top in a linseed oil coating.

Handcrafted from North American hard maple and locally sourced recycled polypropylene, the Precious Plasticaster truly is an instrument like no other.