Building Crib Docks
Building crib docks can pose a few problems, like water depth and lake bottom material.
When considering a crib dock first you should fig the water depth where you plane to place your cribs , you would not want to be placing cribs in water over 10 feet.
Cribs that tall will tend to be unstable and to make then stable you would have to make the bottom section wider than the dock.
Most crib docks are 6 wide or bigger , not that you could not build a small 4 foot crib dock if the water is not to deep .
A 4 foot wide crib will be very unstable if you go much over 6 feet high.
When planning your dock go out on the water in check water depth at location where you plan to put cribs. Checking front and back section of crib location this will tell you the in height from the front timber to the back timber of your crib.
Now before you start building your crib divide the water depth by the timber size
This will help you fig out which way to start your timber so that when you finish your crib the last timber is parallel to the shore so the timber joist will sit on them.
When building the crib once you have put on your first 2 layers you now install 2x8 on top of the first timbers to hold the rocks that will hold the crib down.when joining the timbers I use 10" spikes.
When you have built the crib to where you should be at water level slide crib into water and start adding rocks to where it is starting to sink.
Move crib into place and start filling it with rocks as it slowly sinks make you final adjustment to place it where you need it and fill it right up .
You will find that it probably will not be level this is where you make your final adjustment by adding shims under your last timber you install.
I always place my outside crib first that way I can pull a string line off the crib to the shore to use as a guild to set the rest of my cribs
My way of building crib docks is to use 6x6 for cribs and then I use 4x8 and 6x8 fir timbers for my joist , this way I can use up to 40 foot joist and then I top off my docks with 2x8 decking and 2x12 ring.
While most people would think that dock build is a summer thing it is a lot easier to build them in the winter. Having the ice to walk on can really save time and if you are using machines to help you can drive on the ice when safe.