# Modeling light bulb

### STEP 3

Ok, in this step it is time to model the actual threads. So, for this, we need couple of lines. Just make one below the chamfered part and offset it by 0.9cm down, and that offset curve need to be offset by another 2.3cm.

image 37

Now you need to those two selected lines onto a surface. Do that from front or right viewport.

image 38

Once you got those circles, you can again hide everything except them. Now, we will make another with command and using OSnap Cen option we will easily set the start and end axis of spiral on both centers of two circles (make sure the Turns is set to 5):

image 39

Again, with set to smooth extend both end and start of the spiral so it matches the image 40 below. You might want to use Snap here:

image 40

Now, we will edit this spiral, so either with F9 or with command show the control points, and then move the upper one up just a bit so it snaps to first grid intersection. Do the same for the lower one, just move the control point down:

image 41

From right viewport, create one polyline like on the image 43. Again, it is up to you how big or small you make it. It will be a section for the threads. And fillet the corners with 0.08cm as radius.

image 43

Now, move the little triangle on the start of the spiral. And rotate it so it is somewhat perpendicular to the spiral line:

image 44

Now, explode the triangle, and use only the two angled lines. them.And move them like on the image below: (it is to ensure the surface will go through the thread surface)

move

The problem with moving the section curve is that when you do that, the section gets smaller, maybe the better idea would be to extend the lines. But then again, there will be another problem which is the surface would overlap. So, be careful when extending lines.

And with sweep1 command using Style:Roadlike Top create a surface:

image 45

After sweep1, unhide the surface and the two. You should get something like on the image 46 below:

image 46

Now, using you should be able to fillet the edges with 0.1cm as radius and get this:

image 47

Now, we only need to do one small detail. Add little round holes. Create a radius 0.15cm and position it like so:

image 48

Now, you need to copy that sphere 12 times around. So, using ArrayPolar command and input for the center 0 (zero) and type in 12 copies, and using make holes:

image 49

Ok, now you may use FilletEdge to fillet the edges with 0.05cm as radius. And your bulb is finished.

image 50

### THE END

Ok, if you encounter some problems, please leave a comment and I will try to help. Thanks.

Pages: 1 2 3

used 34 commands

### 13 Responses to “Modeling light bulb”

1. […] this tutorial, naturally, you will need a model of a bulb. So, you should first read and complete Modeling light bulb tutorial and create yourself a model. Oh, you’ve done it already? No you actually just took […]

2. Brad says:

i am having difficulties making a union between the sweeped coil for the threading and the body. do you know why that is?
i just get the message ‘boolean union failed.’

3. Ivan says:

go see image 44-move. You could try extending the two ends of the V curve, and moving it a bit more like on the image. That should fix it.
if you still have problems, please post your image and/or model in the forums under this tutorial and I will help you more.

4. Ever says:

I am having the same problem with the boolean union, it just fails. There is a step I really don’t get and is precisely in the image 44, before that you had a triangle with filleted edge and after that there’s no filleted edge

5. Ivan says:

yes, you are right. Image 44 shows filleted curve, and the move image (img45) doesn’t. If you look at the img46 you will see that one has filleted corner. It is just an error in the image.
But I understand you are having problems, maybe that wasn’t explained the best way, but basically you need to have your section filleted curve positioned perpendicular to the spiral, and with trial and error you should position the curve so when you do sweep1 command you get the surface right. Meaning, it goes through the surface bottom “cap” so you can do boolean union without problems.
I might record a video of this step, it might get a bit clearer. But the important thing is you need to do this by trial and error.

6. Dioniso says:

Great tutorial, although I couldn’t do the FilletEdge of 0.1cm like image 47. I tried everything but it didn’t workout…

About the boolean union problem, just put the section (“little triangle”) on the start of the spiral burt and a move a little bit inside, to the interior (make sure your middle point is not over the end of the line) . You will get a very tiny intersection between the bulb surface and the spiral which will enable the boolean union…

7. Ben says:

What an excellent tutorial, I am so pleased i came across your Web site,
You have chosen great models to be able to cover so many techniques, and commands
Also thank you for answering peoples problems, It really help’s in solving those issue’s we have along the way

Thank Your Very Much
keep looking up cheers Ben

8. Perfect tutorial !
Its my first tutorial in Rhino demo ðŸ™‚
Im a MoI 3D user so its pretty easy to follow
Auxpecker plugin is amazing, this thing should be in every 3D modelling application by default !

9. Norman says:

Hi, i wasn’t able to execute the rib command. Can you please explain more specifically? Thanks a lot!!

10. Bartjan says:

Thanks for the tutorial!! It was a great help.

– Bartjan

11. […] light bulb model was done in Moment of Inspiration 3D using a Rhinoceros 3D tutorial located here It was done in both software for comparaison purposes. Check the other tutorials on the same […]

12. pontif says:

Thanks for that very instructive tutorial.

13. Leon says:

The BooleanUnion as shown in IMG46 always fails. I’ve tried everything. It’s impossible and I don’t understand why. So frustrating …