With momentum still rolling along I started on machining the center spider for the front suspension. This is a multifunctional part that holds the upright legs, defines the steering axis, and connects to the control arms and steering links.
We’ll move along the well-rehearsed path of machine fixture, mount part, machine part, reorient, machine part again. The fixture has several dowel pins to register the part in correct alignment before it is clamped down onto the swivel pads that provide proper spacing and restraint.
Here’s the part clamped in place:
I then machine the part in 3 steps in this arrangement: the top and 2 sides.
These first 3 operations are all done with simple end mills and drills. When I index the fixture 90 degrees to machine the steering stem bearing seats we will need to use some extended reach tooling.
Here’s the 2 flute insert mill used for roughing, the boring bar used for finishing, and the custom long reach retaining ring groove tool made from a slim carbide slitting saw and some precision ground 5/8″ diameter shafting.
Here’s the finished bore:
And some finished parts:
There are 2 different versions of the part, a tall one that provides much less front end brake dive than telescopic forks and short one that provides closer behavior to teles.
Once I do some deburring and test fitting I’ll post some images of the front upright assembly. It will look really cool.
That’s all for now.