Chain is made to standards, so strength, size and properties are quite similar within a given grade and size. Still there can be differences (in galvanizing, for example). For imperial sizes, Budget Marine offers European “Vigouroux” chain, which has the highest standard in consistency and strength specification. For the US sizes, Budget Marine offers the “Acco” range of chain, the most superior available in the US.
When buying chain, you should keep in mind that it must be precise in its dimensions when it has to to fit your gypsy. Dimensions vary by grade and manufacturer. Most windlass producers use the ACCO chain standard. Very often the gypsy of the windlass is worn and is worth replacing – a badly worn gypsy will cause your chain to deteriorate quickly. Check the “shoulders” which grip the chain on the gypsy.
When fitting chain to a specific windlass gypsy, two important measurements, link diameter and pitch, are needed. Link diameter is simply the diameter of the wire used to make the link. Pitch is the internal length of the link. If you have old chain that still fits, you can get a reasonably good pitch measurement by laying out 2 or 3 feet, measuring the distance from the inside of the first to the inside of the last link, then dividing the distance by the number of links. Make sure the chain is taut to ensure accurate measurement, and make sure you measure to the inside of the links.
Important: Please note that all of the working loads “MxWld:… shown for Budget Marine Chain are based on a safety factor of either 25% or 33% of the breaking load, depending on whether the chain has a European rating or a USA rating respectively.