In addition to a small group of common tools, plastic residue can be cleaned from the build platform using 100% denatured alcohol or 100% acetone. Many Acetone nail polish removers can be found at local beauty suppliers or from stores like Wal-Mart for less than $10 USD.
Acetone can be used to clean the build plate between objects, but can also be used to smooth the layered object’s outer surface by melting the outer material – creating a cohesive bond that can be painted or otherwise treated to create a smooth final object form.
The extruded plastic needs to properly stick to the build plate’s surface, which is heated to allow the melted thermoplastic time to bind to the surface before it cools and hardens. Whether using a glass or metal build plate, heated or not – the melted thermoplastic will adhere better if the build plate is covered with a material like KAPTON polyimide film. This material was designed as a temperature-resistant insulating material for the space program and is available in adhesive strips (2mm-120mm).
Placing this on the build plate’s suface without bubbles can be assisted by first covering the plate with a self-drying cleaning liquid like Windex or Glass Plus. This prevents the KAPTON tape’s adhesive from binding until it is aligned and the bubbles removed using a squeegee. After the tape is in place and all bubbles have been moved to the sides, heating the build plate will dry the remaining cleaning fluid and leave a perfectly aligned and flat KAPTON surface covering.
KAPTON-covered heated build plates are the standard “best” option as both PLA and ABS adhere well to the film. However, other techniques have been used by 3D printing enthusiasts and hobbyists to obtain better adhesion between the object and the build plate – particularly those who prefer to use a cold glass plate. Some hobbyists have tried using hairspray such as the unscented “Aqua Net” brand, sprayed across the build plate and allowed to dry fully before beginning the print job.
Others have used ABS Cement, thinned down using a solvent and brushed onto the build plate. This mixture is allowed to dry fully before beginning an ABS print extrusion. A few have taken filament from past extrusions and simply melted this in a solvent like acetone, brushing the resulting fluid onto the build plate and allowing it to dry before beginning to print.
DANGER: All of the methods involving the use of spray propellants or solvents present health risks if not used in well-ventilated areas, and can create a hazard if exposed to an ignition source!
I have not personally tested any of these options involving aerosol sprays or solvents, as I work with young learners and want to protect them from unnecessary hazards. If the first print fails you may simply be able to use it to teach about environmental conditions, thermal expansion and contraction, phase changes and many other subjects while starting a replacement extrusion.