1
Tools & jigs
Router circle-cutting jig
A trammel jig lets a trim router cut clean circles and arcs by pivoting around a pin. The design is a 300 mm arm 60 mm wide and 8 mm thick that bolts to the router base, with 6 mm pivot holes every 10 mm for radii from 50 to 250 mm, a 35 mm bit clearance hole and counterbores for the base screws. Print it flat in PETG with 5 walls so it resists flexing. Open the ready-made model free, resize it on your phone or computer, then download a print-ready STL, 3MF or G-code sliced for your printer, free.Opening the ready-made model and downloading it as STL or 3MF are free, no card; AI changes use credits, from Maker at $7.99 a month.No printer? We print this part and ship it to your door. See its priceUpdated
2
Adjust
Change its numbers in the viewer for free, or ask the AI in the chat: wall thickness, hole size, the thing it clips onto. AI changes use 2 credits per request (1 for a quick edit, 3 for a redesign), paid with a plan from Maker at $7.99 a month.3Print
Download a watertight STL or 3MF free, with your numbers and hand edits, or G-code sliced for your printer at the same price. After an AI change the download is included in every plan (4 credits without one).
Dimensions of the ready-made model (editable)
| Parameter | Value |
|---|---|
| mm | 300 mm |
| mm | 60 mm |
| mm | 8 mm |
| mm | 35 mm |
| distance from left end to bit hole center | 40 mm |
| 60mm circle diameter -> 30 radius | 30 mm |
| through hole for M4 | 4.5 mm |
| counterbore for M4 head | 8 |
| half thickness | 4 |
Example prompt
Design a router trammel arm 300 x 60 x 8 mm with a 35 mm bit clearance hole at one end, three M4 counterbored mounting holes on a 60 mm circle around it, and 6 mm pivot holes every 10 mm from 50 to 250 mm radius.
Fit notes
Router base hole patterns vary by brand, which is exactly why a generic file rarely bolts straight on. SpeakCAD lets you specify your screw spacing, bit opening and the radii you cut most, and produces an arm that fits. Refine the length or add a fine adjustment slot in chat before paying for the download.
Questions people ask about a router circle-cutting jig
A trammel jig lets a trim router cut clean circles and arcs by pivoting around a pin. The design is a 300 mm arm 60 mm wide and 8 mm thick that bolts to the router base, with 6 mm pivot holes every 10 mm for radii from 50 to 250 mm, a 35 mm bit clearance hole and counterbores for the base screws. Print it flat in PETG with 5 walls so it resists flexing.
Click Open it free on this page and create a free account (no card): the ready-made model opens in your browser, on your phone or computer, nothing to install. Change its numbers in the viewer for free and download a watertight STL or 3MF free, or G-code sliced for your printer at the same price. An AI change in the chat uses 2 credits per request (3 for a redesign), and the download after it is included in every plan (4 credits without one). Start with Maker: 50 credits a month for $7.99, cancel anytime.
On this page: open the ready-made model free in a SpeakCAD account (no card), change any dimension in the viewer, then download the STL or 3MF free, or G-code sliced for your printer at the same price.
A shared STL is modelled for someone else's measurements. Here you open the ready-made model free, change it to your measurements in the viewer, then download a file sized for the part you actually own, free as STL or 3MF.
Yes. SpeakCAD slices the part on its servers with OrcaSlicer and your printer's official profile (380+ printers, including Bambu Lab, Prusa, Creality and Elegoo), and you download the G-code (a sliced .gcode.3mf for Bambu Lab printers). G-code sliced for your printer costs the same as the STL: included in every plan, free for a part you shaped by hand, 4 credits without a plan for a part with AI work in it. Pick your printer on the printers page to see its profile.
No. SpeakCAD runs in the browser on your phone or computer: the chat, the 3D engine and the live viewer load in the tab. The only file you download is the finished STL, 3MF or sliced G-code.
Print it your way
More tools & jigs
Elegoo Centauri Carbon purge bucketReady-made, opens free. A 110 × 70 × 50 mm bucket that clips onto the Centauri Carbon's right rail and catches purge before it hits the carbon-fibre bed.Soldering fume-arm 50 mm hose clampReady-made, opens free. A bench clamp that holds a 50 mm extractor hose 200 mm above a soldering iron rest.Shimano flat-mount bleed blockReady-made, opens free. A block that keeps Shimano flat-mount pistons from popping out during a bleed, 22 × 10 × 8 mm.Soldering helping hands baseReady-made, opens free. A weighted base with sockets for flexible gooseneck arms keeps small boards and wires positioned while you solder.Labeled socket organizer railReady-made, opens free. Loose sockets in a drawer cost minutes on every job; a rail with sized posts keeps a 1/2 inch drive set in order and shows the size on each post.Festool Domino DF 500 offset spacer set for shelf jointsReady-made, opens free. A set of stepped spacers that sit under the fence of a Festool Domino DF 500 so mortises land at a fixed offset from the edge for shelf pins, drawer dividers…