One of the columns of the C-7030 is movable, meaning it is adjustable depending on the length of the frame. The adjustment mechanism is in the form of a long screw diagonally anchored into the turntable. This is where the weakness of the design is.
Any screw supporting mechanism is inherently slippery under the full force of string tension. In the C-7030, there is only one screw to support and hold the column from pushing outward. I will take photos later. A picture is better than a thousand words.
if you ever feel the need for an upgrade, you know who to sell the old one to... i will be in VAN in June. perfect timing.
i saw that mechanism at work today. i guess it is not the most secure thing. but then at the same time, the machine that i saw has strung 28,000 rackets (calculated from the number of pulls). so that's should be testament of whether it works well or not.
a bit more about the 7032. i was told that the machine is designed to work for tennis as well, but only for non-oversized racket. and that's partly why they designed it to be suspension instead of clamp down.
It still works but the stringer has to compensate for the shortening by (1) initially stretching the frame and/or (2) using full 10% on the cross tension.
the clamp is similar to what Watdon, UK sells or buy from Victor directly (in the above picture mentioned 750 RMB) or from Pro's Pro I just received my order for 4 pieces of the dual clamp (WA3342) from Watdon. and for the swivel-clamp-base (I believe this is what you meant when said "turntable"), it is similar to at Yonex ES5Protech machine. I've tried to contact the original manufacturer, but they refused to sell.