Installing a pre-drilled thumb insert

1.  For pre-drilled or pre-molded thumb inserts, select "Round" for Hole Type.
2.  If installing a Contour or Turbo pre-sized insert, find the right size insert to fit the sides of the thumb comfortably.
3.  Click "Size" to open the Drop-down list: 

   

   

    

4. When you select the correct size, it will appear in the "Size" box
5. Then click on the "Insert OD" button to open the Drop-down list for the bit size.
6. Select the drill bit size for the correct OD of the insert:

7.  

   

    

   

   
   
8. You can then select the Brand/type of insert by clicking in "Insert type"
   
   1. Turbo Xcel Round / Oval
   2. Contour Round Taper / Oval Thumb Sleeve 
      
   3. Example: 

      

      

       

      

   4. You are all set to drill the thumb !!!!
   5. The process is the same with the pre-sized oval sleeve thumb as the round thumb. 
   6. Note:  If you are using either a Turbo Xcel Oval or a Contour Oval thumb insert, you must align the oval to the proper angle for the bowler before you glue it in permanently.