This instructable will show how to create an external thread in Alibre Design. In this example, we will create a 50mm stud with 20mm of it being threaded (M6x1).

This instructable assume that the user:
1) can create primitives, such as cubes and cylinders.
2) is acquainted with the use of constraints.

## Step 1: Create a Cylinder

Create a cylinder matching you nominal diameter and length.

In this example, I used a 6mm x 50mm cylinder.

## Step 2: Create a Cutting Tool.

Create a sketch that is perpendicular to the end of the cylinder. This means the the sketch we create will "hang off the end" of the cylinder.

1) Create an equilateral triangle.
Note the equal constraint used on each leg of the triangle, as well as the vertical constraint on the outside leg.

2) Dimension the distance from the center to outside leg as the radius.
Helpful Hint: by using the Equation Editor, you can set the dimension to diameter/2; then the cutting tool will follow the diameter of the cylinder if you make any changes

3) Dimension the size of the cutting tool to slightly less than the thread pitch.
This is very important, as this will keep the helix from overlapping when it is created and giving an error.

## Step 3: Create the Helical Cut Feature

Click on the Helical Cut Tool and and enter in the Height and Pitch fields.

If I was thinking a bit clearer, the height parameter would be equal to the distance of thread I wanted, plus one more pitch length, but you can be sure to do that to yours... :)

## Step 4: Making It Look Good... or Is That Well?

You should now have something similar to what is below. But, as you can see, the thread ends rather abruptly. If you wanted something quick and dirty, go no further, but if you need to make it look good, or well, or whatever, then read on...

## Step 5: Select the End of the Cut

Click on the Face where the Helical Cut was ended.

From the Toolbar, select Project to sketch.

Hint: If you choose Maintain associativity, the new sketch will follow the face if it changes.

Click OK

## Step 6: Cut It Out!

Take this new sketch and Extrude Cut. You'll have a nice, clean feature.

Something to note: A helix is a rather file intensive, so you'll see your file size grow quite a bit.

Method 2 takes a more cosmetic approach. :)
I suggest adding a filet to the cylinder before cutting the helix. This will more nearly emulate actual threaded fasteners. If the fastener is to be a hex or Torx socket head, I suggest revolving a longitudinal half cross section instead of extruding a circle. I noticed that most of the comments are fairly old. Since these were written, Alibre has added many features to their software. I am using Alibre V11 Standard but the "Pro" and "Expert" versions have a thread tool.
Hi hunter, thanks for noticing the instructable! The current thread tool will not have a noticeable graphical representation until you make a drawing-- well it will add a fillet on the end... ;) Also, if you look at my last step, I don't recommend this method unless absolutely necessary, due to the huge increase in file size.
I belive that you are correct and there is almost no reason to use the helical cut to make threaded fasteners. Iam going to start using Method 2. Unless a person is using exploded views or sections there isn't even a reason to make the threads at all.
Yep! In fact, method 2 is what I used in my <a rel="nofollow" href="http://jcclark.drivehq.com/Screw_Selector_2_0_beta.zip">Screw Selector</a> API Program (Shameless plug, I know, but I still offer it for free-- someday, I may even get to finish it).<br/>
Correction to my previous post. Memo to brain: Think first, type second. I meant "Chamfer" not "Filet"
When i go to the helical cut dialog, it wont let me select what axis i want. "axis" will turn bold, but it wont take any axis. also the "ok" button is grayed out it has done this before. help please
Hi John. You're right in that you can't select an axis, but when you dimension the distance to the center, (in this instance, it happens to be an axis), it will put in a reference line. The reference line is what you will use for the axis. You can see what I mean by the picture of the dialog box in Step 3. :) I'll admit it, this kicked my tail feathers a few times for the same thing, so don't sweat it too bad.
Its complicated because Alibre is very basic. More advanced programs like Inventor simply have a thread tool which you click, select the object to thread, select pitch and such, and click ok. Alibre is fine for people modelling their home projects, but for any business you should buy Inventor or Solidworks.
This is really for when you <em>really need</em> to design a thread.<br/><br/>Bear in mind that Inventor and Solidworks threads are cosmetic (or lightweight, if you prefer), and add no substance to the model itself. I agree that it would be nice if Alibre had a similar lightweight thread option. That being said, Alibre is being used in industry and manufacturing. And rather successfully, too! True, Alibre doesn't have the bells and whistles of other packages, but it does do 95% of what I need in machine design, and the other 5% I've found ways to make work. <br/>
at first i didnt reall get it, but it looks complicated.
The helical features seem to be the most difficult to master. Like most software, it does what we tell it to do and not necessarily what we want it to do! Helical features are also big by nature, to it can really inflate the file size. I suggest not using it unless it's really necessary to the intent across. ;)