I am looking at a 4 ft x 20 ft T-shape dock kit from Tommy Docks. In their instructional video, they simply set the edge of the dock on some pavers on shore. No posts, no pouring concrete, no brackets. That certainly would make installation easy, but I am a little worried about the end of the dock being unconstrained. Does anybody see a problem with this approach?
Just my experience, but don't add the deck pad exactly like they showed. You do want the pad feet, but I always tighten it just under the deck, and drive the post down with a t post driver. Make sure the deck pipe is in the corner bracket and that will help keep the pipe vertical. If the pipe footer hits the ground, then raise it again, and drive it down some more. I try to hit clay, and that may be a foot or 2 foot down, and that's plenty. I've got one 2 tier Tommy Dock deck that's held on a near 45 degree angle for years. You may need to use a block or screw a 2X4 to the dock to keep it level while you set the posts.
I may not be an expert on Ponds, but I am a builder and have built a few docks. The Tommy dock systems are definitely easy and seem to hold up, but definitely do not just set the first panel on blocks like that. That will add additional strain on your first set of posts, and essentially put all the horizontal strain from the first panel onto those. I would add additional posts at the shore line, This will prohibit any horizontal sway in the event of a storm/ flooding, and only allow the dock to float up and down as intended. You definitely want to drive the posts as deep as possible, and the feet are a good idea to support any strain from the sides. Id leave them loose till you drive the posts then tighten at ground level. If water is too deep to do so just use the auger style, and still the deeper the better. Also like FireIsHot said make sure they are as level as physically possible! If they don’t go down strait the distances between them will increase or decrease and that I’ll prohibit proper dock movement. For those docks to hold up you need to make sure that every panel is supported on 4 sides from horizontal movement and only allow the dock to float up and down, not left and right, set post as deep as physically possible, and as level as possible. If done correctly it will last a long time! Also YouTube post setting leveling jigs and there a bunch of ways to DIY a simple jig with some 2x4s to assure you drive them level.