Loose aft lower shroud

Anonymous 121765 · Oct 19, 2015

Celtic,
Depending on your rigging tuning set, under load My lower aft shrouds can sometimes show alittle slack from time to time depending on conditions & sail sets.

If only slightly slacked, this should not be of concern in 15KTS. That being said, if unsure, hopefully you have tensioner gages to check on the rigging tension, uppers lowers, fore & aft or, a friendly neighbor that does.

CR

Anonymous 121765 · Oct 19, 2015

Celtic,

I forgot to add, that for a slight semblance of rake in my mast, my forward lowers are slightly tensioned more than my aft shrouds. Not by much but, I sometimes see a slightly aft shroud slackening at different sail angles, sets & conditions.

CR

FastOlson · Oct 19, 2015

Celtic_Wind said:
We're fairly new to sailing and had an interesting, and concerning situation last Friday.
We own a Catalina 30 and were on a port tack, full sails, with 10-15 knot winds. I looked over and the aft lower shroud was visibly loose. None of the other shrouds appeared to be loose.
Neither the Admiral or I had noticed this happening before, and I was concerned enough to have her steer into the wind, drop the sails and motor back in.
At the slip, all the shrouds seem to be fairly tight, but what do I know...
Thoughts and advice would be greatly appreciated.

Did you pull enough backstay on to put any bend in the mast when setting up to go to weather?
If so, that might have loosened the forward lower but not the aft one. How do the shrouds look at the top ends?
Given that you have an '83 model, there is a (slim, but real) chance that your boat still has the original standing rig. As a rigger friend of mine might put it: "Yikes"....
I would inspect all of the rigging and also the chainplate structure very (!) carefully. If the attachments pass muster, then it is a decade past time to put a new standing rig on that boat.
Be safe...

Regards,
Loren

Jdaniel343 · Oct 21, 2015

I had a mast go overboard this summer due to failure of the swage's to turnbuckles. This was new rigging I had made up by a reputable rigging company. We are still discussing the issue of the swage's they performed.
From now on I am going to paint a small white ring around the shroud where it enters the stud. This way I can see if the wire and stud are not moving away from one another.
My shrouds became loose during sailing but I attributed this due to the shrouds were new and were stretching. I have a feeling that the shrouds were pulling out all summer long as I tightened the turnbuckles more often than I would have expected.

woodster · Oct 21, 2015

was that company in florida or local

Jdaniel343 · Oct 21, 2015

It was not in Florida. I am still working with them so I won't give out the name.

woodster · Oct 21, 2015

Jdaniel343 said:
It was not in Florida. I am still working with them so I won't give out the name.

thank you

Displacesailor · Oct 26, 2015

Check both upper and lower swag fitting a s well as chain plate attachment. Look for leaks at the chain plate that might be an indication of deck or chain plate failure.
If no mechanical problems were found have the mast completely re tuned. A loose lower aft shroud is general not a problem if the mast is in column and has little or no rake in those kind of conditions.
If it is too loose and allows the mast to pump to much or the mast is out of column there is an increased of bending or breaking the mast.
Some very small change in the mast tuning is common from season to season. Re tuning the mast must be done when it is taken down and at least once each year even if you are just cruising.

jrowan · Nov 25, 2015

You never mentioned if the aft lower shroud was in the same side as the boom, or the opposite side. If the loose shroud was on the same side as the boom, that is the starboard side on a port tack, then this is a pretty normal occurrence. The more you heel in heavier air, the more pressure is exerted on the rig, especially the shrouds which are under load, on opposite the side of the boat where the boom is. The shrouds on the port side are really taking all the load from the sail pressure, which can cause the opposite lower shrouds to slacken slightly, as the mast is actually bending slightly when under heavy load. The other issue that most sailors don't account for is that when the boat is under heavy load, the hull & cabin top can flex slightly, in a reaction to the heavy load that the mast, rig, deck & hull must absorb & displace. This can change the tension of the rig temporarily & over time. As long as the shrouds are still tight when the sails are down & the mast is not under load, then the rig should be fine. Only if you see cracks in your turnbuckles & loose wires in the shrouds or stays should you be really concerned. It is more important to not over tighten the rig or create an imbalance. I have my mast raked slightly aft with my tensioner to create better performance in heavier air. One area though that many sailors overlook are the cotter pins that hold the fore & backstays in place. Catalina used some pretty cheap cotter pins, & I had one fail on a C 25 that I used to own. I almost lost the mast when the cotter pin failed & split. It was only quick thinking that I spun the boat around & went down wind to take the load off the forestay that saved my mast from falling backwards. That was a scary wake up to me to replace all the cotter pins in every boat I've had since. Most sailors never look at the condition of the forestay attachments to the deck, as they are often blocked from view by a furling drum.