I would like to add say 100 ft of Anchorplait or similar to anchor chain on main anchor. Which is best? Rode on a thimble & shackle or spliced on to the chain?
If you are going to put it round a windlass or feed it through a navel pipe into an anchor locker you would need to have a splice as a shackle would probably jam. Otherwise, having a hard eye and shackle means you could deploy it for other purposes such as a tow-rope (if you could get the shackle undone).
Go for the splice. If nothing else it makes handling the join more comfortable and it will run through the bow roller (and windlass if you have one) without any risk of snagging. I take Alan's point about the tow rope but if you use a shackle it should be secured with wire which would make undoing it in an emergency doubly difficult.
Also one less "weak point" in the system.
I think the first two responses covered the choice. I personally would go for a splice as there is less chance of a hardware failure. Very good instructions for splicing anchor plait to chain can be found in the Jimmy Green Marine catalogue.
IMHO it depends how much chain you already have. If you have enough for normal use and want to add the Anchorplait in exceptional conditions, I would use a thimble and shackle. This is my option with 60 metres of chain. Stowing 100 metres of Anchorplait in the average chain locker is a nuisance and I for one can do without it.
On the other hand, if you have about 20 metres of chain I would splice the rope to it permanently.
both anchors currently feed into the fairly large locker through pipes, with the main on the windlass. I thought about extending the all chain(225ft) main rode with about 75-100ft of something like anchorplait or megabraid. The secondary rode has 24 ft of 1/2 inch chain and about 180ft of 3 strand connected with a thimble & shackle, which I am in two minds about replacing with about 300ft of the easier to stow anchorplait or similar.
I use a thimble and a calibrated shackle, always use calibrated after vyv's excellent article in pbo a while back.
My reasoning, I have two 40m rodes connected to anchors (via the chain) that can be removed easily to be used as extra long shore lines or any other use where a nice long rope is required.
Though I have not done this since buying a nice coil from the boat jumble's mr. rope which is just kept at a long long line for towing, shore line, etc etc.
I still like the idea that I can quickly change anchor rodes, or even extend the rode if that was ever required, I have a thimble on the bitter-end of one of them.
I'd have them separate with no hard eyes. You never know when you might want a really long line. Just tie it on when needed. Use proper knots. Ashley Bend for and ideal line to line bend. Anchor bend for the chain.
Hard eyes can be a nuisance but will come into their own when you really need them. If you anchor in a big blow, then add rope to your chain without hard thimbles, will you sleep soundly? Rope can wear through very quickly.
I live with the inconvenience of the thimble, either on my kedge or on the bower warp, secure in the knowldege that it should continue to be there when needed.