At 09:39 AM 8/26/2015, dofunk@yahoo.com wrote:
>     Aren't the bars a fixed length? So weather the assist is good
> or bad that shouldn't affect the tension of the canvas or the bunk
> hitting the roof. If the bunk hits the roof when opening its

They're only a fixed length until the upper one starts cutting
through the crossbar tubing, then they get shorter and shorter as the
cut progresses.

YOurs,
David