Introduction: Furniture Knobs Modeling | SelfCAD

About: Student at the Faculty of Civil Engineering at the Silesian University of Technology

Welcome to the next SelfCAD instructable.

Are you looking for ideas for handles for your furniture? Why don't you print your very own knobs? In this tutorial, I'm going to show you 4 simple ideas for these furniture parts.

All you need is imagination and your SelfCAD account.

The first three ideas are really simple, I created them to show you how easy and fast it can be to make your own knob. The last one is, according to me, much more interesting.

Step 1: Create New SelfCAD Project

Launch SelfCAD editor and create a new project. The workspace size 100 should be definitely enough, but I set here 200mm just to have more space to show you all four knobs.

Now you can change the preferences if you want. ,

Turn on Orthographic Projection (next to the Rotation Cube).

Step 2: Knob 1: Add Two Cylinders to the Scene

Let's make the first knob. We need here two cylinders.

1st cylinder has its radius of 10mm and height of 30mm.

2nd cylinder has a radius of, for example, 5mm. Its height can be also 30.

Step 3: Knob 1: Rotate and Move the Second Cylinder

Use the Rotate tool (R) to rotate the second cylinder as in picture 1. Then use Move (M) and place the rotated cylinder as shown in picture 2.

Step 4: Knob 1: Subtract Second Cylinder From the First One

Select both cylinders and use Stitch & Scoop, Difference (B+D) to subtract the second cylinder from the first one.

Step 5: Knob 1: Make a Hole for the Screw

First, you should know the screw diameter and length. The hole should a little bit narrower and deeper. Notice that the screw must also go through the furniture front. Let's say we need a hole 2mm in diameter and 15mm deep (can be less, but more than protruding part of the screw).

Add a cylinder to the scene with a radius of 1mm and height 15mm. Use Stitch $ Scoop to subtract it from the knob.

This step applies to all knobs. I won't describe it anymore in this tutorial.

Step 6: Knob 2: Add Two Cylinders to the Scene

The second knob is composed of three 3D shapes. First, add two cylinders to the scene.

1st cylinder: radius 10mm, height 2mm.

2nd cylinder: radius 3mm, height 5mm. Move the second cylinder 2 mm higher to place it on the first cylinder.

Step 7: Knob 2: Add a Sphere to the Scene

Add a sphere to the scene. Set its radius to 15. Move the sphere 6mm higher.

Step 8: Knob 2: Use Union

Select all three objects and use Stitch & Scoop again, but this time use Union, not Difference. They should "merge"* into one object now.

Cut a hole for the screw.

*There is also a Merge tool and it works similarly, but not the same.

Step 9: Knob 3: Repeat Steps 6-7

This knob is similar to the previous one, so repeat the first two steps (Steps 6 and 7).

Step 10: Knob 3: Scale and Move the Sphere

This time use Scale (S) to decrease the sphere's Y dimension. Move the sphere lower to connect it with cylinders.

Step 11: Knob 3: Complete the Knob

Use Union and make a hole for the screw.

Step 12: Knob 4: Use 3D Sketch to Draw Profiles

The first three knobs were very easy. The last one is a little bit harder but definitely the most elegant.

Choose 3D Sketch tool and then Circle Sketch (K+C). Go to Precision Settings and turn on Minimum Step Size. Set its value to 1. Change the number of Edges to 24 (24 looks good, but it can be any other EVEN number).

Go to Planes Settings.

Step 13: Knob 4: Draw Circles

Draw circles from the workspace center and change the plane's offset in Plane Settings:

1. Offset 0, radius 10
2. Offset 2, radius 10
3. Offset 2, radius 3
4. Offset 7, radius 3
5. Offset 10, radius 10
6. Offset 15, radius 12
7. Offset 20, radius 10
8. Offset 22, radius 4

The result is shown in the last picture.

Step 14: Knob 4: Turn on Loop Selection

Apply the drawing. Click on the Vertex Selection Mode and open Selection Settings. Turn on Loop Selection.

Select two neighboring vertices of the biggest circle. The whole loop should be selected now.

Turn on Custom Pattern. Now, every two vertices should be selected.

Step 15: Knob 4: Scale Selected Vertexes

Use Scale to change the shape of the circle into a star. Do the same with two circles neighboring circles. Look at the image to see the result.

Step 16: Knob 4: Use Loft to Connect the Circles

Turn off Vertex Selection Mode and select the whole profile. Use Loft (C+L). Make sure you have selected Fill First and Fill Last options in Fill Settings.

The knob looks quite good right now, but we can do some more things with it.

Step 17: Knob 4: Twist the Knob

With the knob selected use Twist tool (D+W). I twisted it -90 degrees.

Step 18: Knob 4: Round Object

Use Round Object (M+R).

Step 19: Knob 4: Complete the Knob

Cut a hole for the screw and delete the profile. The knob is ready.

Step 20: Use SelfCAD's Built in Slicer to Generate Gcode and Print Your Knob

In the photo you can see the forth knob just after I printed it and cut the support out.

Good luck with modeling your own knobs!