How can I join two pieces of anchor chain?
QWe have an Arcona 400 which we keep at Plymouth yacht haven. We bought her because she is well built, a delight to sail, is reasonably quick and can accommodate our daughters and their young families. We mainly cruise locally with the occasional racing event for charity. We plan a cruise to south Brittany this summer. I have 45m of 8mm anchor chain, hardly sufficient for anchoring my boat in a range of wind and tide conditions. I have a further 30m of 8mm chain sitting in my garage, but is there any safe way of joining the two together? Will this joint pass through the anchor winch? Alastair Paramore
AVyv Cox, a chartered engineer specialising in metallurgy, replies: The only fastener that will join two lengths of chain and subsequently pass through a windlass is a C-link. Two C-shaped half links are riveted together to form a single link that can be stronger than the chain, but not in all cases. Sold in many chandleries, the C-links are either cheaply made from mild steel or somewhat more expensively from stainless steel. Neither of these is likely to be as strong as Grade 30 chain but in most cases will be adequate for occasional anchoring. Industrial links sold for use in lifting and hoisting are made from heat-treated alloy steel that when made up, is at least as strong as Grade 40 chain. The most widely available in the UK are those made by Crosby, marketed as the Missing Link. Alloy steel C-links require heavy hammering to make up the rivets, unlike the other types that are relatively soft and therefore easy. In service, both steel types will corrode faster than the chain to which they’re connected. Painting and regular inspection are recommended to extend their life. Stainless-steel types are far less prone to corrosion and this property may be considered more important than their lower ultimate strength. Industrial suppliers will not normally supply C-links in small numbers. One good source of single items by mail order is Tecni-lift (www.tecni-lift.co.uk).