# Start the First Prong
### **Curve tab: Arc Command**
To start, go to the **Curve tab** and locate the **Arc submenu**. Use the **Start, End, Point on Arc** command.
Create the curve as follows:
* **First point:** Click slightly to the left of the gem's fillet.
* **Second point:** Click a square and a half below the central axis on the bottom side.
* **Third point (arc point):** Click approximately midway between the first and second points.
Ensure the middle point is horizontally aligned with the top point, as shown in the reference image.
### Pipe Command
Now, select the arc and go to the **Solid** tab and select the **Pipe** command.
In the command prompt:
* Set **Output** to **SubD**.
* Choose **Cap: Round**.
* Enter **0.6 mm** for the pipe diameter and press **Enter** twice.
### SubD: First Prong
Switch to the **SubD** tab (1), use **Face Selection** (2).
* From the **Top View,** hold **Shift** and select the **four top faces** of the prong.
* Click on **Merge Faces**.
Adjust the prong:
* Use the **Gumball** tool to proportionally scale down the selection.
* In the **Front View**, move the selection upward to form a tapered tip.
* Position the prong to align with the gem's crown center.
*To position the prong, you can create a line like the one in the image; this will help you have a reference.*
Use the gumball in the **front view** to move only the **red** and **blue** arrows to position the tip of the prong. To visualize what you are doing, use the other views, especially the perspective view and the top view. It’s important to move only from the front view to avoid altering the alignment of the prong.
**Top View**
**Front View**
**Perspective View**
### Refine the prong edges
* Switch to **Edge Selection Mode**.
* Double-click the last horizontal edge of the prong.
* Rotate whith the **green** circle and smooth the edge using the **Gumball** tool.
### **Video Lesson**
{% embed url="" %}
### **Next Step**
Position the prong around the gem and prepare to mirror it.
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