Gantry rigidity question

Hello all,

On my home built CNC plasma table I'm getting some significant wobbling / shaking on intricate cuts when there is frequent changes in gantry direction and accelerations. These result in sawtooth cuts which are getting to be a pain. I'm wondering if anyone knows or could speculate if changing from a C Beam extrusion (photo included) to 3 of these 20x80 extrusions (see other photo) tied together along the length would improve the rigidity? Looking at a video of a cutting session I can see the Z axis shaking back and forth at a relatively high rate which is why I think it's the gantry. My belts are all super tight and there is nothing catching on the X or Y axis rails.

Thanks in advance for any help or opinions.

 

Peter,

Thanks so much for both ideas...I really like the dual beam idea! I think I'm going to start in on design of that one.

Scott