[Keith Hardy]

Originally Posted by nota2266

At the bottom you have two C posn and two D posn C1 forward, D2 forward.
the swing radius of the system is a bit more complex
Initially swings thru A-C1 but then the C-D link modifies the radius to an imaginary point. if A, C1, C2 all on same line , much better but difficult to achieve.

That's easy for YOU to say.

Thanks for the offer of sketches. I'm goin' mad trying to keep up with all this...