Stick your finger in the holes (Onshape Tutorial)

Hello beautiful Onshape users. Today I’m going to teach you how to make a bowling ball. If you’re a Fusion 360 user and you’re reading this, switch to Onshape. You can thank me later.

A bowling ball is one of those things that doesn’t sound hard until you start trying to make one. You can make holes in any program, but it’s hard to make them normal to the surface.

When you’re done, it should look like this:

1. Start by making an arc on the Front plane. Not just any ol’ arc; a center-point arc. Start by clicking the origin to make it the center of the arc. Move your cursor straight up and click, then straight down and click to set the end points. Draw a vertical line connecting your end points. So far so good:
   
2.  Revolve around the center line
3. Unhide the previous sketch. Create a new plane, select from the drop down menu to make a plane from a line. Select the center line from the previous sketch and type 60 degrees. IGNORE THE WARNING!
4. Make another plane from the center line. This time make it 280 degrees. KEEP IGNORING THE WARNING!
5. Here’s where it gets tricky. Make a new sketch on Plane 1. Use the Use command on the sphere, it will give you a circle. Draw a straight line from the origin to the top of the circle. Draw another line from the origin to the north-east edge of the circle. Define the angle to be 35 degrees. Like so:
   
6. Do it again on Plane 2.
7. Unhide (Show) all sketches.  Create a plane, pick from the drop down: Point normal. It’s usually for normal people but we can use it anyway. Select the top point and the center line. (And confirm it by hitting the green check mark).
8. On this new plane, create a sketch of a single point on the origin. Easiest step ever!
9. Create another plane from Point normal by selecting the separate point and it’s line.
10. On this second plane, create another sketch with a point on the origin.
11. Make the plane and the point on the other sketch. With me so far?
    
12.  Use the hole tool on the three points you made. 25mm wide and 27mm deep.
13. Add a filet of 3mm on the edges of the holes. Done!