I am assuming you have the "scissors" table then? The V21 had two versions of the table. First run models had a two leg twist lock table and later models had the scissors table.
Although the twist lock table top did work, we opted to make a custom plywood space filler with a leg. This allows for a wider bed use and still supports 2 adults easily.
You can follow other modifications on other parts of the forum.
And at
https://www.facebook.com/Terry-Classic-V21-by-Heartland-175194559719464/
Our trailer must be a first-run as the dining table had two twist-lock legs. When two kids are attempting to sleep with the dinette table in the bed position, the table flips downward on the outside edge and the cushion slips out. Appears to be an issue with the two side supports being too short and the table itself being too short (front to back).
Not only is the table unstable when placed in the bed position, it is five inches too short (front to back) when seated at the dinette. One has to lean over the table or move uncomfortably close to the table since the table legs are fixed and the table itself is five inches too small.
I contacted Heartland this morning and they offered to ship us the newer style scissors style table as a replacement. The newer style table is the correct depth for the dinette area (larger table). I'll remove the two twist-lock floor mounts and patch the screw holes. Most likely, I'll need to replace the two side supports with longer pieces of wood to support the larger table.