Rigging tension

[surfynic]

Hi there guys and girls!

I'm nearing the end of a 3 year complete re build of a Simpson 12 cat (when she's in the water I'll share some pics of what was a huge undertaking!) and we've just raised the mast with all new rigging. Now that it's up and standing tall how the heck do I figure out how tight to do up the wires?? The mast is 17m with 10mm ss wires. Happy to answer any other questions to help!


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[Suijin]

Are you looking for rig tension data specific to your Simpson, or just general rig tuning guidelines and processes?

[surfynic]

Just general guidelines. I have no idea how to know how tight the rig should be! Ive heard horror stories about over tightened rigs!

[Suijin]

OK.

There is plenty of online information. Just Google "sail rig tuning" and you'll get loads of results from sail and rigging companies. I just scanned this one and it meshes up with in general what I know from working with riggers and tuning race boats.

Your first step is to get the mast in column. Rake and pre-bend, if any for your boat, are boat specific and you should look for information on those from other Simpson owners. If you've not changed the rigging then start with the old settings, which will probably give you ballpark rake and pre-bend and focus on getting the mast in column.

Once you have that set, tighten your shrouds down until they are "snug" and free of any play. How loose your leeward shrouds are when you're sailing is going to be a function of how stiff your boat is. Ideally you don't want them flopping around, but you don't want to over tighten them either, which is a risk on a small cat. Again, if there is Simpson-specific information out there it would be a good idea to hunt it down.