Tim,I make all the drowners I sell,and use myself out of cable.
I make them out of 3/32 and 1/8 inch cable.The 1/8 lasts a lot longer than the 3/32.Each end is adjustable so they can take any size stake or even be put around a small stump or rock.Each one has a drowner lock ,that the trap is attached to.I use snap clips hooked to the end of my traps,to attach to the drowner lock.
I use 3 differant sizes: 5 foot,8 foot and 10 foot.A wooden stake is used at the upper end near the trap,like you,I stretch the other end--out tight into deep water.This end is staked with a 2 foot rerod stake.
Here's a little tip,if your drowner wire is longer than you need,or the water gets deep quick--and you can't wade out far enough to get it tight,run it at an angle,down the shoreline,instead of straight out.
These can also be used on dry land to get your catch away from the set,and hidden from others sight.
Tom