GFLabel

Generates labels for labelled gridfinity bins (primarily pred and Cullen J Webb labels), and similar generate-smallish-printable-label uses. Leverages build123d.

State

This is an early version of a hobby project. Thus:

• It has a lot of rough edges, not the least that the output is messy and not very useful. But functionality not used much might not work well.
• It sometimes needs manual encouragement to make labels looking good or consistent.
• A habit of sometimes crashing OCP when geometry is a little bit odd.

Usage

Installation

You should be able to install into your favorite python-virtual-environment manager by just using pip:

pip install gflabel

This should work on most modern platforms, but with the following caveats:

• Linux wheels for the dependency cadquery-ocp are only available on resonably modern (e.g. Ubuntu 22.4+) linux distributions, so you may have to go to conda to install on an older machine.
• For specifically macOS arm64, the underlying cadquery-ocp library is not available as a wheel through pypi. In this case, you will have to set up the build123d environment manually. build123d has some notes on resolving this conflict.

Otherwise, you can check out this repository and pip install it directly, or install directly from the github repo:

pip install git+https://github.com/ndevenish/gflabel.git

Basic Examples

By default, labels are written to an output file "label.step". You can change this with -o FILENAME. .step, .stl and .svg are recognised

A simple, single label generation on a pred-style base:

gflabel "Basic Label" -o basic.step

Symbols are specified with { curly braces }. If you specify more labels than divisions (which defaults to one), then multiple labels will be generated with a single call:

gflabel "{nut}M2" "{nut}M3" "{nut}M4"

Or, if you specify divisions, then you can generate a multi-bin label (in this example, a margin is also added to ensure that the labels are not too dense):

gflabel --width 2 --divisions=3 "{nut}M2" "{nut}M3" "{nut}M4" --vscode --margin=2

You can span multiple lines, mix text and symbols, and some symbols can be passed configuration (e.g. in this case the bolt length is dynamically specified as 20mm):

gflabel "{head(hex)} {bolt(20)}\nM2×20"

Some symbols can also take many modifiers for e.g. drive or head type:

gflabel "{head(+)} {bolt(50,slotted,round)}\nM3×50"

And multiple label styles/symbol styles/fonts can be selected:

gflabel --base=webb --font=Arial "M3×20{...}{webbolt(+)}"

Command Parameters

Core command parameters (call gflabel --help for the full list):

usage: gflabel [options] LABEL [LABEL ...]

options:
  --base {pred,plain,none,webb}
                        Label base to generate onto. [Default: pred]
  --vscode              Run in vscode_ocp mode, and show the label afterwards.
  -w WIDTH, --width WIDTH
                        Label width. If using a gridfinity standard base, then
                        this is width in U. Otherwise, width in mm.
  --height HEIGHT       Label height, in mm. Ignored for fixed-height bases.
  --depth DEPTH_MM      How high (or deep) the label extrusion is.
  --divisions DIVISIONS
                        How many areas to divide a single label into. If more
                        labels that this are requested, multiple labels will be
                        generated. Default: 1.
  --font FONT           The font to use for rendering. [Default: Futura]
  --font-size SIZE_MM   The font size (in mm) to use for rendering. By default,
                        this will be adjusted to fit the label horizontal area.
  --margin MARGIN       Margin area (in mm) to leave around the label contents.
  -o FILENAME           Output filename. [Default: label.step]
  --style {embossed,debossed}
                        How the label contents are formed.
  --list-fragments      List all available fragments.

Defining Labels

Labels can consist of:

• A physical base, which is the object that the labels are extruded out of (or cut into).
• Regular text, including unicode symbols (although complex symbols like emoji are unlikely to render properly, or at all - this is down to the underlying library).
• Newlines, either explicitly typed in (e.g. at the terminal), or escaped by writing \n in the label definition. Each line will be rendered separately, but still constrained to the same label area.
• Fragments. These are directives enclosed in {curly} braces that add symbols or define an area on the label.

Let's go through each of these:

Label Bases

The base (specified by --base=TYPE) defines the shape of what the label is generated on top of. Currently, the following bases are understood:

Base	Description	Image
pred	For Pred's parametric labelled bins labels. If specifying this style, then height is ignored and width is in gridfinity units (e.g. --width=1 for a label for a single 42mm bin).
plain	For a blank, square label with a chamfered top edge. The specified width and height will be the whole area of the label base. You must specify at least a width.
webb	For Cullen J Webb's swappable label system. Label is a 36.4 mm x 11 mm rounded rectangle with snap-fit inserts on the back. Use without margins to match the author's style labels.
none	For no base at all - the label will still be extruded. This is useful if you want to generate a label model to place onto another volume in the slicer.

Symbols/Fragments

Along with text, you can add symbols and features to a label by specifying "fragments". These are directives enclosed in {curly braces}.

A list of all the fragments currently recognised:

A basic set of examples showing the usage of some of these:

Bolt/Screw Drives

The {head(...)} fragment, and any other fragments that will accept drive head types, takes a feature specification for the kind of drive that you want to represent. These are stackable, so you can specify multiple drives and they will be overlapped. Examples of using the drive types are:

Bolts and Screw Heads

There are two classes of bolt/screw representation:

• bolt corresponding to the Pred's printable label bin bolt style. This is used simple as {bolt(LENGTH)}, where LENGTH is the length of the bolt/ screw stem that you want (excluding the height of the head). If the label area is too small to fit the entire bolt on, then the bolt will be rendered with a "break" in the middle, indicating that it does not show the whole bolt length. It will also accept a slot feature that marks a small indent on the top of the head, and flanged in order to render a washer-style flange at the bottom of the active head.
• webb corresponding to the bolt style included with Cullen J Webb's swappable gridfinity label system. It doesn't change length, but it will accept any combination of screw drive specifier and display them in the bolt head.

Both types of bolts will accept a head style, one of pan, socket, round, or countersunk. Both can be marked as tapping to have a pointed tip, and both can be pointed backwards by adding the flipped feature.

Examples showing some differences between the two bolts: