Threaded Bolt in Rhino3D

Threaded Bolt in Rhino3D

The trick is :
Sweeping the cross section of the thread along 2 curves, two concentric spirals with the pitch of the thread.


This is a quick and dirty tutorial for making a 3D threaded bolt in Rhino 3D. Once you have made your own 3D thread scaling, cutting and pasting will give you all other sizes.

The bolt head dimensions are avalaible on the internet, I have added two pictures to this blog to spare you searching for basic info on thread and head dimensions.

Making the basic bolt cilinder and head are considered basic Rhino3D skills so goor luck!
One suggestion is to work very precise, type in de dimensions and you grid snap where possible.

The most difficult part for me was making the thread.
Following the below basic steps you will be able to replicate the M10 thread.
I drew a M10 bolt and the dimensions mentioned in the tutorial are for an M10 with fine thread which has a 1.25mm pitch.

1. Draw the thread very precisely.
You can use the dimensions from the figures at the end of this tutorial.

2. I place this thread and the helper lines on the side of the M10 bolt shaft cilinder.

3. The spiral curve is drawn, with its axis along the cilinder axis of the bolt with a diameter of 10mm and a pitch of 1.25mm.


4. This spiral is copied and transformed by scaling it 2D in the "circular" plane. Resulting in a 8.2mm diameter spiral. (with naturally a 1.25mm pitch also)

5. The thread will be made by creating a surface by sweeping the thread along these two spirals. The thread will have to be split to size, see the drawing below. I use the two squares to do that very precise. It is this selected curve that will be swept along the two spirals.

6. Once you made your spiral surface/thread all that is left, is cutting off the front and capping it.
Cutting the start of the thread and connecting it to the bolt cilinder.

The "official" thread dimensions:

Enjoy making it,

The trick is : 
sweeping the cross section of the thread along 2 curves, the two concentric spirals withe the pitch of the thread.