Thread
Put a screw thread on a round face, inside a hole or round a shaft: cosmetic for drawings, or modelled for 3D printing.
- Thread AdvancedPart Studio toolbar
| SchoolCAD | Onshape | Fusion | SOLIDWORKS |
|---|---|---|---|
| Thread | – | Thread | Thread Cosmetic Thread |
Thread puts a screw thread on a round face of a part: the inside of a hole (an inside thread, like a nut) or a round shaft (an outside thread, like a bolt). It reads the size from the face, so a 5 mm hole becomes an M6 thread (5 mm is the tap drill for M6) and an 8 mm shaft an M8 thread. It works like Thread in Fusion and SOLIDWORKS.
A thread can be cosmetic or modelled:
- A cosmetic thread only marks the face as threaded. Engineering drawings show it the way industry does (a thin three-quarter circle, and a callout such as M6 × 1). Use it for parts made in the workshop, where a tap or die cuts the real thread.
- A modelled thread is cut into the part: the real ISO 60° thread, ready to 3D print, so a printed part takes a real bolt or nut, or two printed parts screw together.
Thread is an Advanced tool. For a tapped hole, the Hole tool can make the thread too.
How to use it#
- Make the part with a round hole or a round shaft. For an inside thread, make the hole the tap drill size (Ø5 for M6, Ø6.8 for M8): the Hole tool's Tapped type does this for you.
- Click Thread.
- Click the round face: the inside of the hole, or the side of the shaft. The dialog says what it found, such as Outside thread M8 × 1.25, 25 mm long.
- Change the Size, Length or Hand if you need to.
- Tick Modelled thread to 3D print it.
- Click ✓.
Options#
| Option | What it does |
|---|---|
| Face | The round face, and its diameter. Click another round face to thread that one instead. |
| Size | To fit the face picks the ISO metric size the face fits. Or choose a size (M1.6 to M24), or Custom. |
| Major Ø / Pitch | Custom only: any diameter and pitch, such as a jar lid: Ø60 with a 3 mm pitch. |
| Pitch | The coarse pitch (the usual one) or a fine pitch (ISO 261), such as M10 × 1.25. |
| Length | Full length: the whole face. Or untick it and type how long the thread is. |
| Offset | How far from the end the thread starts, in mm. |
| Start | The thread starts at the open end of the face (the top of the hole, the end of the shaft). ⇅ From the other end starts it at the other end. |
| Hand | Right hand (almost every screw and bolt) or Left hand (the left pedal of a bike, gas fittings). |
| Starts | 1 to 4. A thread with two or more starts goes in faster (a jar lid often has two). |
| Modelled thread (for 3D printing) | Off: a cosmetic thread. On: the real thread is cut. |
| Print fit | Modelled only: extra room in the thread, in mm, so a 3D print does not bind. 0.1 to 0.3 mm suits most printers. |
Tips#
- A modelled thread runs right out through an open end, as a tap or a die leaves it, so the bolt starts easily.
- Modelled threads are heavy (thousands of triangles). Add them last, after the rest of the design is done.
- For an inside thread, the hole should be the tap drill size. If it is not, the dialog says what it should be.
- To 3D print a nut and bolt that fit each other, model both with the same size and pitch, and give one of them a Print fit of 0.2 mm.
- A thread that is not ISO metric (a jar lid, a bottle cap) is a Custom size.
- For a spring, or a thread that is not on a round face, use Coil.
If it does not work#
- Click the round face to thread: the inside of a hole, or a shaft. Click the curved side of a round hole or a round shaft. Flat faces and faces that are not round all the way along cannot be threaded.
- The hole (Ø6) is as wide as an M6 thread. Drill the hole at the tap drill size (Ø5 for M6), or choose a bigger thread.
- The shaft (Ø5) is too thin for an M8 thread. Make the shaft the size of the thread (Ø8 for M8), or choose a smaller thread.
- The face has other holes or cuts across it where the thread goes, so it cannot be modelled. A modelled thread needs a plain round face. Move the Thread above the feature that cuts across it, or use a cosmetic thread.
- The round face to thread has gone. An earlier change took the face away. Edit the thread and click the face again.