Why a six bar on the top?

MasterCole · January 16, 2018, 1:48pm

So we’ve seen a lot of people use a six bar instead of a four bar at the top of their primary lift. Is there any reason for using that over a four bar?

Neil_6121C · January 16, 2018, 1:52pm

It can reach higher than using a four bar on the top

Mystellianne · January 16, 2018, 1:56pm

There’s two main reasons.

Provides additional height for little additional metal.
The fact that the bottom bar is cut short leaves more room for the mogo four bar at the base.

CannonT · January 16, 2018, 2:07pm

In addition to reaching higher, the top six bar is also able to fold into a slimmer horizontal profile than a pure reverse double four bar. This is because, with a six-bar on top, the top bars of the lift will hit the ground later, which allows the whole thing to fold down more compactly within the robot.

Here is an MS paint diagram to show this.

Silicon · January 16, 2018, 7:09pm

So we can directly gear the bottom and top together and still get decent height. Also increases stability at the top, since there is larger vertical distance between the bars.