Getting started

From opening the app to a part on your print bed: the three tabs, and how to save and share what you make.

Connector Foundry is a catalogue of printable mounting parts — Gridfinity bins and baseplates, openGrid snaps, Skådis pegs, Honeycomb Storage Wall inserts, MOLLE panels, GoPro buckles, Arca plates, tripod sockets, MagSafe mounts, 2020 extrusion fittings and more — written as parametric OpenSCAD. Every part follows the same slot convention, so any of them can be attached to any other: a GoPro buckle on a Gridfinity base, an openConnect head on a Honeycomb Storage Wall insert. You set the sizes, check the part in 3D and download an STL for your slicer.

#Open the app

The web app runs at dnnsmnstrr.github.io/connector-foundry/app/ in any current browser, on a computer, a tablet or a phone (Safari or iOS 15.4, Chrome 93, Firefox 114, Samsung Internet 17, or newer). There is nothing to install and no account to make. Parts render on your own device, with OpenSCAD compiled to WebAssembly, and nothing you make is uploaded anywhere. The first render of a visit takes a few seconds longer while the engine loads; after that most parts render in a second or two on a computer, a few seconds on a phone.

On a phone or tablet the 3D view comes first. The part list (and on the Bench and Holes tabs, everything that is in the sidebar on a computer) is a drawer at the bottom of the screen: tap its handle to open it, or drag the handle to pull it up or push it down (Find a part opens it at its search). The part's settings are in the drawer too, on a Parameters tab beside the Parts list; the tabs show on the closed drawer, and tapping one opens the drawer on it. Drag with one finger to turn the view, pinch to zoom, and tap a handle to type a size.

Install it like an app. Settings → Install the app (or the command palette's) adds it to your home screen: on Android, Chrome asks to install it; on an iPhone or iPad, tap Share and Add to Home Screen. It then opens from its own icon, full screen, and once it has rendered a part it opens again without a connection. It keeps itself up to date: when a new version is out, Reload to update (Update on a phone) appears at the top, and the next time you open it fresh it is there anyway.

Want it in a window of its own, or offline? The desktop app is the same app for macOS and Windows. To render parts from scripts, there is a command line.

The app has three tabs, at the top of the window (or the keys 1, 2 and 3):

#Print your first part

1. Pick a part. The Library lists every part by system on the left; type in Search parts… to narrow it down. If you are not sure where to start, try Gridfinity → Bin. The part renders with its catalogue defaults, and the line under its name says how to print it: which side goes on the bed, and whether it needs supports.
2. Set its size. Change a parameter in the sidebar and the part renders again. A dot marks a value you changed, and the ↺ beside it puts that one back; Reset all puts every one back. Most parts can also be resized in the 3D view: drag one of the small square handles, as in TinkerCAD. An outline shows the new size before you let go, with a label such as "W 126 mm · 3 cells", and the part renders once you do. Parts on a grid grow in the grid's own steps — a Gridfinity unit is 42 mm. To type an exact size instead, click a handle.
3. Check the outside dimensions under the part's name: width, height and depth in millimetres, as rendered.
4. Download STL (under the 3D view) and open the file in your slicer, or upload it to EasyPrint to print it from a phone (below). On a phone or tablet, Print… beside the part's name has the download. With Layerling, Copy for Layerling skips the file and pastes the part in directly.

Each part says how far to trust it. exact parts come from the standard's reference implementation or its published specification, and are checked against someone else's model of the same standard (see Accuracy checks). parametric parts are a good starting point: measure your hardware — the webbing on your bag, the slot in your rail — and print a test piece first.

#Print from a phone with EasyPrint

Prusa's EasyPrint slices a model in the cloud and sends it to a printer on Prusa Connect, all from a phone's browser or the Prusa app. No website can hand it a model directly (it has no way in for other sites), so getting a part there takes three steps. Print… walks you through them: beside the title on a phone or tablet, in every tab. On a computer it is Print with EasyPrint… on the Bench and Holes tabs, and in the Library Download STL is the first step.

1. Share STL… (or Download STL) puts the file on the phone. On an iPhone or iPad, the share sheet's Save to Files keeps it where EasyPrint can find it; Chrome and Android save it to Downloads, since Chrome's share sheet refuses model files. 3MF is the same part a fifth of the size, and on the Bench one 3MF holds every body.
2. Open EasyPrint and sign in with your Prusa Account.
3. In EasyPrint, Models → Add… → Upload model, pick the file, choose the printer and Print.

The part was set up on your computer and the printer is next to your phone? On the Bench, Send this bench to another device (in the command palette) shares the bench's link, or copies it: open it on the phone and print from there.

#Fit it to your printer

Two settings change every part, under ⚙ Settings at the top right (or the s key):

• Fit clearance is the gap left where two printed parts slide or snap together, 0.15 mm by default. If snaps are too tight on your printer, raise it a little; if they rattle, lower it.
• Circle detail is how finely curves are faceted: Draft renders faster, Fine gives rounder holes.
• Grid sizes changes the Gridfinity cell size and MOD-GRID hole spacing for a printer or a nonstandard grid. The same values affect part previews, Bench attachments and the Holes tab.

To keep your own values for one part — "my Gridfinity bins always have magnet holes" — set them and click Save as my default. User overrides has the details. Settings can hide the systems you never print from the part lists, and Export settings… saves all of this to a file, to move it to another browser or to the desktop app.

#Combine parts on the Bench

The Bench builds one part out of several:

1. Choose a base part (or Open in Bench from the Library, which brings its parameters along).
2. Click a green slot marker on it. A picker opens over the scene: pick the part to attach, and the joint beside the search — Fused into one piece, Bolted with heat-set inserts, Snap-fit, Pinned or Screwed. Joints explains each one.
3. Adjust the attached part in the sidebar: its own parameters, an offset, a shift across the slot, a rotation. Click it in the scene to turn it in 90° steps, move it to another slot (M), or delete it.
4. Export. Every printable body of the bench gets its own STL button: a fused bench is one body, a bolted one is two halves you print separately and bolt together.

A bench can start from a model of your own, too: Import STL / STEP / 3MF…, or drop the file on the empty Bench. The Bench guide covers resizing the base part, cropping, presets and importing.

#Drill holes into anything

The Holes tab takes a part from the catalogue, a model of your own or the bench as it stands, and cuts into it. Click a face and a hole snaps to the useful places on it: the middle, the middle of each quarter, a point set in from each corner, the middle of a hole already there, and the guide lines between them. Pick what to cut from the presets: socket cap screws from M2 to M6, countersunk and button heads, heat-set insert bores, nut traps, wood screws, magnet and bearing pockets, and the slots that take openConnect, MultiConnect, Skådis and MOLLE hardware. Select a hole to move it, or drag a cutout's handles to resize it. The Holes guide lists every preset.

For custom Gridfinity storage, start Holes from Gridfinity → Bin with filled on: a bin that is solid up to its stacking lip, ready for pockets shaped like your tools.

#Find anything with Cmd/Ctrl+K

Cmd+K on a Mac, Ctrl+K elsewhere, or the magnifier (Search) button at the top right on a phone or tablet, opens the command palette: type a few letters to switch tabs, find a part, pick a hole type, attach, export, undo, change a setting or open a guide like this one (holes guide). The first letters of words work too — oib is Open in Bench. Press ? for every keyboard shortcut and the mouse and trackpad controls; Cmd/Ctrl+Z undoes in every tab.

#Let an AI agent use it

In a browser with WebMCP, the app tells the browser's AI agent what it can do: the command palette's commands, the parts catalogue with each part's parameters, opening a part in any tab, attaching parts on the Bench, what each tab shows, and loading a whole bench. Ask the agent for "a 3 by 2 Gridfinity bin with magnets" or "attach a flat plate to this board's corner slot" and it works the app as you would. Opening a part over your bench or holes asks you first, and anything the agent does to a bench can be undone with Cmd/Ctrl+Z. As of October 2026 that is Chrome with chrome://flags/#enable-webmcp-testing turned on; elsewhere nothing changes. The desktop app offers the same to coding agents like Claude Code.

#Save and share

• The address bar is a link to your bench. The app keeps the bench in the URL as you work, so a reload comes back to it and the link opens the same bench for someone else. The app also remembers the whole workspace — the tab, the Library's selected part, the bench with its imported meshes, and the Holes document — in this browser, so closing and reopening it (or relaunching the desktop app) comes back to what you were doing. Imported meshes are too big for a link: they stay in this browser, and a config file moves them to another device. Send this bench to another device (in Cmd/Ctrl+K) shares the link through your device's share sheet, or copies it; from the desktop app, the link opens the bench in the web app.
• Download config (on the Bench) saves the whole bench to a .bench.json file, imported meshes included, to open again later from Import config….
• Presets keep benches you reuse in this browser.

#Next steps

• Desktop app: install it on macOS or Windows.
• Command line: render parts without a browser, with your saved defaults.
• Bench, Holes and Joints: everything each tab can do.
• Found a problem, or a part that does not fit? Open an issue — measurements of the real thing help most.