Materials: PLA, ASA, and what we refuse to print

The short version

The softening figures are heat deflection temperatures from filament makers' published data, measured at a light load. They are where a part starts to sag under its own weight or a light push, not where it melts.

PLA, for indoor pieces

PLA is the default for a reason. It is stiff, prints with sharp corners and clean letters, holds dimensions well, and comes in the matte colors we stock: black, white, slate grey and sand, with red and moss for letters. At room temperature a PLA bin, tray or plaque keeps its shape indefinitely.

Its weakness is heat. Around 55 degrees Celsius, 131 Fahrenheit, it starts to soften. A room, a drawer or a desk never gets there. These places can:

• A closed car on a warm day. Interiors pass 60 C regularly, and dashboards go well above that. See what happens to PLA in a hot car.
• A dishwasher. Wash and dry cycles run hotter than PLA likes.
• A sunny windowsill or a south facing shelf in summer, where a dark piece in direct sun heats far above the room.
• A radiator top, a warming drawer, a spot right above a toaster or a stovetop.
• A closed metal shed or a truck box in summer.

Keep PLA pieces out of those spots and they last.

ASA, for sun and heat

ASA is a weather resistant cousin of the plastic in many car exterior parts. It is UV stabilized, which means it is formulated to hold its color and strength in sunlight for years, and it does not soften until about 95 degrees Celsius. We use it for the number plaque outdoor option, for mailbox posts, gates, sheds and dock boxes.

It costs more and prints slower, in a heated enclosure, which is why it is an option at $29 plus the material upcharge rather than the default. UV stabilized is not UV proof. Over many years any plastic in full sun will fade a little.

If you need another piece in ASA, like a wall plaque on a covered porch that gets afternoon sun, email [email protected] and we will quote it.

Finish and tolerance

Every piece is printed in layers about 0.2 mm thick. Flat faces come out smooth. Curved edges show fine layer lines, which you can see in every product photo; that is the nature of the process and not a defect. The face of a desk name plaque prints against a textured build plate and comes out with an even matte texture.

Dimensions hold within a few tenths of a millimeter on small pieces and about 0.3 percent on large ones. That is why our measured products leave a set clearance, 1 mm each side on bare card trays, 1.5 mm in total on box inserts, 1 mm on baseplates and 2 mm on divider kits. The post on what printed to fit means explains the numbers.

What we refuse to print

Some things we do not make at any price, and the list is not about difficulty:

• Anything that touches food or drink. Printed layers have tiny crevices that hold bacteria, and we will not make a claim we cannot stand behind. No cookie cutters, cups, plates, scoops or utensils.
• Toys and products aimed at young age groups. They carry their own safety rules and third party testing, and we do not design for them.
• Loose magnets, in anything.
• Characters, logos, brand marks and trade dress. We print your text, not someone else's intellectual property. School and company logos included.
• Safety critical parts. Nothing that holds weight over people, restrains anything, protects a body, or replaces a part in a vehicle, a ladder, a car seat or a medical device.
• Weapons and weapon parts.

When a request falls outside the line, we say so plainly and, where we can, point to what would do the job.

Where we print

Every piece is designed and printed in our own workshop in the United States. The filament itself is made by established filament manufacturers, mostly overseas, which is why we never call a product made in a particular country. What we make here is the design, the generator that sizes it to you, the print and the check against your numbers.