# Smart 3D Modeling Blog Series: Parametric Bolt with Provision of Split Pin Hole - Blog 3 of 3

In this blog we will create a Split Pin hole on the parametric bolt that we created in the previous blog. The location of the split pin hole and whether the bolt will have a split pin hole, will vary based on variations of the bolt size. Follow the steps below to create the split pin hole on the bolt:

1. Create a hole with diameter 2 on the lower portion of the Shank.
2. Now create two Local Variables to control the split pin hole:
• Split_Pin_Location = Shank_Length (R*3) – Chamfer_Equal_Distance [(R/10) *1.34] – 2
• Split_Pin_Yes/No = 1 (For value 2 or higher, the Split pin hole will not show on the bolt)
3. Select Show Input Feature for the hole.
4. Apply 3D Dimension constraint associated with Split_Pin_Location variable, to the center of the hole from the top edge of the shank.
5. Hide the input feature of the hole using the Hide Input Feature tool. The Bolt is now ready with provision for split pin hole.
6. Now add Entity Size Filter with Hole Diameter value associated with the variable Splt_Pin_Yes/No and then identify the bolt (solid) to apply the filter. The value of Splt_Pin_Yes/No variable will decide whether a variation of the bolt will have the hole or not. For value, equal to or greater than 2, the hole will not show on the bolt.
7. For some variations of the bolt, keep the value of Splt_Pin_Yes/No = 2 or greater so that for those variations the split pin hole will not be visible. For example, set Splt_Pin_Yes/No = 2 for M20, M24 and M30 in order not to show the split pin hole.
8. Test the parametric bolt by applying the variations from the variables dialog.

The parametric bolt is ready for use. Such a parametric bolt can be used where many different bolt sizes are used in design. This eliminates the need to create different cells for each bolt size and type manually and saves time.

(You can view the sample DGN for this blog here). Click here to read other blogs on parametric modeling.