Glossary

Here is a plain-language list of every important term from this book, grouped by first letter so you can skim and find what you need.

A

Additive manufacturing. Building an object by adding material a little at a time, usually layer by layer, instead of cutting it away from a solid block. 3D printing is the everyday name for it (see Chapter 1).

ABS. A common plastic (acrylonitrile butadiene styrene) that is tough and heat resistant but prone to warping and smelly fumes. It needs an enclosure and good ventilation, so it is not the friendliest choice for a first printer.

Adhesion. How well the first layer of plastic sticks to the build plate. Good adhesion keeps the print from popping loose partway through.

ASA. A plastic similar to ABS but more resistant to sunlight and weather, so it holds up better outdoors. Like ABS, it prefers an enclosure.

B

Bed leveling. The process of getting the nozzle the same small distance from the build plate across the whole surface, so the first layer is even everywhere. Many newer printers do this automatically.

Boolean operation. In CAD, combining shapes using set logic. Union fuses shapes into one, difference subtracts one shape from another (to cut a hole or pocket), and intersection keeps only the overlapping region. These three operations build most printable parts.

Bridging. Printing a flat span of plastic across a gap with nothing underneath, like the top of a doorway. Short bridges print fine; long ones sag and need support.

Brim. A flat ring of plastic printed around the base of a model, attached to its edges, to improve adhesion and fight warping. You peel it off after printing.

Build plate (bed). The flat surface the printer builds on. It is often heated and may be a removable spring steel sheet you flex to release the finished print.

C

CAD. Computer-aided design: software for drawing 3D models on a screen. Tinkercad and OpenSCAD are the two CAD tools used in this book (see Chapter 8).

Calipers. A measuring tool that reads distances to a fraction of a millimeter, far more precisely than a ruler. You use them to measure a lemon, a slot, or a printed part so your designs fit.

Chamfer. A flat, angled cut across an edge or corner. A small chamfer on the bottom edge of a part can hide elephant's foot and helps a part start into a slot.

Citrus press. A handheld tool that squeezes juice out of citrus fruit by pressing the cut half against a ridged dome or through a strainer. The lemon squeezer in this book is one.

Clearance. The deliberate gap left between two parts that should fit together. Too little and they jam, too much and they wobble. Also called tolerance.

Clog. A blockage in the nozzle or hotend that stops plastic from flowing. Causes include debris, burnt plastic, or printing too cold.

E

Elephant's foot. A slight bulge or squish at the very bottom of a print, where the first layers spread wider than the rest. A small chamfer on the bottom edge hides it.

Extruder. The motor and gears that grip the filament and push it toward the hotend. Some printers mount it on the print head (direct drive); others mount it on the frame and feed through a tube (Bowden).

Overhang. A part of the model that leans outward steeply or sticks out with little support beneath it. Past roughly 45 degrees from vertical, overhangs start to droop and may need support.

F

FDM / FFF. Fused deposition modeling (and the equivalent name fused filament fabrication): the method where the printer melts a plastic string and lays it down in layers. This is the affordable, common type of printer this book uses.

Filament. The spool of plastic string that an FDM printer melts and prints with, usually 1.75 mm thick.

Fillet. A rounded blend on an edge or inside corner instead of a sharp angle. Fillets look nicer, feel better in the hand, and reduce stress where parts could crack.

First layer. The very first layer printed onto the bed. It matters most, because a good first layer sets up the whole print to succeed (see Chapter 5).

Food grade. A regulated, tested claim that a material and the way it was made meet official safety standards for contact with food. A home FDM print cannot honestly make this claim, because you cannot test or certify your own process.

Food safe. In everyday use, "safe enough for careful personal use." That is the realistic goal for a home-printed squeezer: choose a sensible plastic, keep it clean, and use it gently for yourself, while knowing it is not a certified food-grade product (see Chapter 14).

G

G-code. The plain-text instructions a slicer produces that tell the printer exactly where to move, how fast, and how much plastic to push. The printer reads this file and follows it line by line.

H

Hotend. The heated metal end of the print head that melts the filament just before it reaches the nozzle.

I

Infill. The internal pattern that fills the inside of a print. You set it as a percentage; more infill means a heavier, stronger, slower part (see Chapter 5).

J

Juice vesicle. The tiny juice-filled sacs inside a citrus fruit segment. These are the little bags that burst and release juice when you press a lemon.

L

Layer height. How thick each printed layer is, set in the slicer (for example 0.2 mm). Smaller layers look smoother but take longer to print.

Layer shift. A printing fault where part of the model suddenly slides sideways, leaving the upper section offset from the lower. It usually comes from a belt slipping or the head bumping something.

M

Mechanical advantage. The way a tool lets a small effort do a bigger job, usually through leverage. A squeezer with long handles or a wide press multiplies the force from your hand.

Model. The 3D shape you design or download, before it is sliced. It is saved in a file such as STL or 3MF.

Module. In OpenSCAD, a named, reusable chunk of code you can call many times, optionally with parameters. Modules keep a design tidy and let you repeat a shape without copying it (see Chapter 10).

N

Nozzle. The small brass or steel tip with a tiny hole that the melted plastic flows through. The hole size (often 0.4 mm) affects detail and print speed.

O

OpenSCAD. A CAD program where you design by writing code instead of dragging shapes. It is great for parametric, adjustable designs (see Chapter 10).

P

Parametric. Describes a design built from adjustable values, so changing one number (say, lemon diameter) updates the whole model. OpenSCAD is parametric by nature (see Chapter 10).

PETG. A plastic that is tougher and more heat and moisture resistant than PLA, while still printing fairly easily. It is a reasonable pick for a squeezer that meets water and acidic juice.

Pith. The white spongy layer between a citrus fruit's peel and its flesh. It tastes bitter, which is why a good strainer holds it back.

PLA. The easiest beginner plastic (polylactic acid). It prints at low temperatures and rarely warps, but it softens in heat and is not the most durable.

Pour spout. A shaped lip on the squeezer that guides the collected juice out in a controlled stream instead of dribbling everywhere.

Press fit. A join where one part is pushed firmly into another and held by friction alone, with no glue or screws. It relies on the right clearance between the two parts.

Primitive. A basic built-in shape such as a cube, sphere, or cylinder. You combine primitives with boolean operations to make complex parts.

Print in place. Designing and printing an assembly, including moving parts, all at once so it comes off the bed already working, with no assembly needed. It depends on careful clearances between the parts.

R

Raft. A thick lattice base printed under the whole model to help it stick and to give an uneven bed something flat to build on. It uses more plastic than a brim and is peeled off afterward.

Reamer. The ridged, cone-shaped dome of a citrus press that you twist the fruit against to tear the vesicles and release juice.

Retraction. Pulling the filament back a little when the print head moves across open space, so it does not ooze and leave strings. Tuning retraction reduces stringing.

S

Skirt. A loop of plastic printed near the model but not touching it, to prime the nozzle and let you check the first layer before the real print begins.

Slicer. The software that turns your 3D model into printer instructions (G-code), deciding layers, infill, supports, and speeds. It is the bridge between design and machine (see Chapter 5).

Spaghetti. The tangled mess of stray plastic strands left when a print fails and the printer keeps extruding into thin air. A vivid sign something came loose.

Spool. The reel that the filament is wound onto. Printers hold the spool on a holder so it unwinds smoothly.

STL. A common 3D model file format that stores an object's surface as a mesh of triangles. Most downloadable models and slicer inputs are STL files.

Strainer. The part of a squeezer with holes or slots that lets juice through while holding back seeds, pith, and pulp.

Stringing. Thin wispy hairs of plastic left between parts of a print, caused by oozing during travel moves. Better retraction and temperature settings reduce it.

Support. Temporary printed scaffolding placed under overhangs and bridges so they do not droop. You remove it after printing, and it can leave rough marks.

T

Tinkercad. A free, beginner-friendly CAD tool you use in a web browser by dragging and combining shapes. It is where this book starts designing (see Chapter 8).

Tolerance. The planned gap or allowance between parts so they fit as intended. Same idea as clearance; designing with realistic tolerances is the heart of parts that fit (see Chapter 9).

Top/bottom layers. The solid layers the slicer prints at the very top and bottom of a part to close it off. More of them gives a smoother, stronger surface.

TPU. A rubbery, flexible filament. It can make grippy or bendy parts but prints slowly and can be fiddly for beginners.

3MF. A modern 3D model file format that can store more than just the shape, such as colors and print settings. Many slicers prefer it over STL.

U

Under-extrusion. When the printer lays down less plastic than it should, leaving gaps, thin walls, or weak layers. Causes include a partial clog, printing too cold, or filament not feeding well.

W

Wall (perimeter). The outer shells of a print, traced around the edge of each layer. More walls make a part stronger and the surface more solid.

Warping. When a print lifts or curls off the bed, usually at the corners, as the plastic cools and shrinks. It is most common with ABS and ASA and least with PLA.

Z

Z offset. A fine adjustment of the nozzle's height above the bed for the first layer. Setting it correctly is key to good first-layer adhesion.

👉 Where to go next: more projects. With the vocabulary in hand, the last chapter points you toward what to print after the squeezer.