I've gotten a few questions on how I did my downrigger on my Hobie. Here are some pictures showing the mounting of it. The downrigger is a Scotty Depthmaster 1050. First is the Hobie H-Rail Universal Mounting Plate. Attached to that is a Scotty 1010 manual downrigger mount. The downrigger can now be easily taken on and off for transport. I switched out the downrigger wire with 300ft scotty braided line, I think either 175lb or 200lb test. You want to change out the wire because it vibrates much more than the braid, and you will feel that vibration in the kayak. Also braid creates far less drag, which means you do not feel like your kayak is trying to turn whatever side the downrigger is on, plus there is less blowback which is important being in a kayak, you can't use as heavy a ball. I went for so much line in case I ever am in a fire drill and have to cut the line asap, I should still have plenty left.
The Hobie universal mount is tightened to the gills on the h-rail. I used pliers and really snugged it up til I couldn't snug it up any more. If you do not snug it up extremely tight, once you put the weight of the ball on, the mount will lose bite on the rail. To help with getting a "bite" on the rail, I also positioned the mount at about a 45 degree angle up. I've used 4, 6, and 8lb balls fine so far. I prefer 4lb, am comfortable with 6lb, and keep a close eye on 8lb. With any of them though, once you are rigged, lower the ball into the water slowly, don't just let it drop. That's a lot of torque being applied to the rail and the mount if you just drop it. I lower it into the water holding the clip.
The only thing I still might do is shorten up the boom arm. It's not bad, but it is a small reach to grab the line/ball.
Hope this helps those that have been asking.
