The rust and wear are typically at the working end of the chain. No need to toss it all out.
Since it's rare to pay out the whole length you might just cut off the bad section and you're good to go with a shorter chain.
But there is another possibility - add some new chain using a link at the back end which is perhaps a tad weaker but this weak link will be aft of the working part and the chain stopper and so the working chain is not weakened.
You can even use a strong shackle which will not pass your windlass gypsy
, and you'll have to pass this chain joint manually into the chain locker, but then you can use the windlass
for all the rest of the chain.
I typically use 100' a chain for my anchoring
which is mid point of my 200' rode
and occasionally use 150', but your anchoring
grounds may be very different.
Don't waste your time and money
re galvanzing the entire length for a small bit of chain. A bit of rust is not weakening the chain.