Replace chain on floating dock - recommendations?

[JASinIL2006]

Hi all, we have a floating dock at our cabin in Ontario. The floating part is comprised of two 10' x 4' sections, attached end to end (with removable dock hinges and pins) to form a finger dock 20' long. This attaches to a stationary dock on shore with hinges and removable pins so we can take the dock over winter. We are in a fairly sheltered cove; we rarely have chop greater than 1' or so.

We currently anchor the lake end of the dock (farthest from shore) using two criss-crossing chains connected to concrete deadman anchors on the lake bed, situated about 4' outside of the dock's width. The depth of the lake is about 12-14' at the end of the dock and does not fluctuate much over the season. The chain is in the water year-round; when we pull the dock, we attach a rope to the clips on the chain and tie the rope to shore so we can easily retrieve the chain when we want to reinstall the dock the following year. The chain we're currently using has rusted badly and needs to be replaced.

My question: what is the best type of chain for this application? Stainless? Galvanized? I'm also not sure what the optimal thickness is for this use; we currently have fairly heavy chain, in part to help contribute to the weight that helps keep the dock from moving too much in waves/wake. I think we used 3/8" originally.

Thanks for any ideas/sources you care to offer.

 

[Lectro88]

Well you have several options when it comes to chain.
Not sure what I provide is what your looking for but its another option.
I use 5/16, 3/8 & 1/2 Grade 70. (way heavier than you need) you can probably get by with 1/4" chain.
My chain is not the gray galvanized, its kinda gold colored.
here's copy and paste description.

Durable Material
By adopting superior electroplating process, zinc plated chain is designed for long service time and prevented from corrosion, rust and deformation.

my application is not submerged in water 24/7 but they sit outside on a trailer or dump truck. I use it to bind equipment.
And it still looks good after 6-7 yrs. with job site abuse.

Shackles, I would splurge for stainless if you use those.
I use a lot of shackles, Galv & stainless.
All this stuff can be found on ebay. But its gone up a bunch since I bought/purchased.
I have about 200' feet of chain. and a tool box full of shackles.

maybe this was some help.

 

[Chris1956]

I would expect galvanized chain used for boat anchors (proof), to last 20+ years in fresh water. 1/4" chain or heavier if you want should work.

 

[Lectro88]

Something I left out,. just in case.
If you decide you need to cut Grade 70 chain, you need a grinder with cut-off wheel or a torch.
It laughs at a hack saw. it just slides across it.

 

[rallyart]

I use galvanized wire rope and galvanized chain and connectors on my dock. My water goes up and down 14' so my set up is much different on the floating dock than yours and my storm waves can get over 5'.
That said, you can easily use all stainless without a lot of extra cost as your chain lengths are not long. If you go with stainless you are better to keep everything stainless as mixed metals can make the stainless get a bit more brittle. If your water is acidic corrosion is faster so there are greater benefits to Stainless. My lake is slightly basic.
Heavy chain takes longer to wear but costs more so that's just a balance in effort to replace vs. cost. In your situation I think I'd go with a heavy stainless chain but using galvanized would not be a mistake. It's just choice.

 

[alldodge]

I would normally go galvanized but...
The chain that is there now, how long did it last?

Not to side track, and taking docks in will make then last longer, but what about full float using pipes?

My marina holds a few hundred boats using pipes (depths vary zero to 20 or so feet). About a 4 ft piece of pipe is attached to the dock. Another pipe is inserted into the first which goes down and sits in the mud on the bottom. Dock just rides up and down as level changes.