What is PLA?
PLA is a popular 3D printing plastic material that features a lower melting point and more shallow learning curve for individuals new to 3D Printing.
Generally considered the more environmentally friendly option vs its popular alternative (ABS), PLA is plant based and made from starches like soybeans or corn. Because its composition includes starches, PLA tends to emit a faintly sweet smell during printing. After printing, objects will need a little time to cool before handling to let the plastic finish bonding. Aesthetically, PLA-printed objects usually have a glossy finish, and they tend not to warp as much as ABS objects. However, PLA doesn’t have as high a flexing tolerance as ABS. It’s more likely to snap when bent.
In the unprinted filament form, PLA should be kept out of humid environments. If left in a humid location for an extended period of time, PLA will absorb moisture from the air. This can lead to unwanted bubbling or spurting from the nozzle during printing. Furthermore, there’s risk of discoloration as a result of the additional moisture in the PLA. To reduce the risk of allowing the filament to absorb too much moisture, it should be kept in a cool, dry, airtight container.
Though PLA hardens when it cools, objects created with it shouldn’t be left in hot places (like the inside of a car in the summer). When exposed to excessive heat, these printed objects can droop and lose their form.
Getting the best results from PLA filament involves using a few techniques that are specific to this type of plastic. One of the most important factors for ensuring quality prints is to adjust the printer’s heat settings appropriately. PLA has a lower melting point than ABS, so the nozzle temperature should generally range from 190-240 degrees Celsius. We recommend that you always refer first to manufacturer temperature guidelines included with any specific roll of filament that you purchase. Unlike ABS, PLA doesn’t require a heated build platform, but it can use one. For best results, the platform’s temperature should be set between 40 and 50 degrees Celsius – any hotter than that, and the plastic may not harden. Again, we recommend that any manufacturer temperature guidelines included will a purchased roll of filament be tested prior to exprimenting with other settings. Manufacturer recommended temperatures are often tested on a regular basis, and will differ between manufacturers (and may even differ between batches of filament from a single manufacturer, based on the exact properties of that specific batch).
The adhesion between the first layer of PLA and the build platform is crucial to an object’s formation, but the plastic doesn’t always stick properly to the platform. To help ensure better adhesion, we recommend that you either cover the platform with blue painter’s tape or spray it with hairspray. When selecting your approach, do keep in mind that the hairspray may leave an unwanted residue on the platform.
What is PLA best for? PLA is best for objects that won’t need to face harsher conditions like extreme heat or contact with chemical solutions. It’s also a great material for schools using 3D printers as educational tools – the plastic’s lower melting point makes it a little safer to work with than ABS. It’s also ideal for artists, due to its ease of use and glossier finish. However, if you want to print extremely intricate designs, interlocking assemblies, or pin-joints, you would likely benefit more from ABS.
Check out our side by side comparison of PLA vs ABS.