SO 35 rigging

[2953]

04 SO 35 transported and now being rigged for this season for the first time. However the manual fails to provide sufficient detail to confirm orientation of the multiple shrouds. Seeking counsel for the following:

1-each spreader (2) has a wire clamp with two "captures" for shrouds, one fore and one aft. Should the upper shroud be clamped in the fore position at the upper spreader or the aft position?

2-pending #1 above, should the upper shroud, then, descend to the same position on the lower spreader? (This would then answer where the intermediate shroud would clamp).

3-with upper, intermediate, and lower shrouds at deck level, what orientation should be made to the 3 position chainplate?

4-no mention in the manual of respective cable tension. What is recommended tension via Loos gauge?

Thanks for guidance. Manual remains disappointing in its lack of detail with multiple basic but essential items. Unable to find previous guidance on this forum as well.

[zaphod]

I wouldn't expect the manual to go into such detail as I think it is assumed that professional riggers would be doing that kind of work, and to them it would likely be obvious. My 39i came with a Selden tuning guide that was separate from the owners manual, and even it doesn't go into the details you are looking for.

Your best bet is to find a SO35 that is rigged and have a close look. Unfortunately we don't have any in our club or I would snap some pics for you. Perhaps someone else here can do that for you.

As for loos gauge numbers, you should be able to follow a generic tuning guide to make sure the mast is straight and in column. Exactly how much tension depends on the type of conditions you sail in.

For insurance purposes you may want to enlist the aid of a rigger to help you step your mast and inspect it. It is not something you want to take chances with, particularly if you have no experience.

[Charlie-Bravo]

If I could get to my boat I would gladly take some photos, but alas that isn't going to happen just now.

Rig tension and rigging in general is a science in its self, and in my experience even some professional riggers seem to make it up as they go along, some with Loos gauges some with just a casual twang of the rigging. I do my own tensioning, but it's not a 'set and forget' thing, and to be set up correctly needs also to be observed and felt whilst sailing for the final tune.
A good read is the seldon hints and tips you will find on their web site, this gives lots of information.
As Zaphod said, the final setting of the rig will depend on use.
This lockdown could give the opportunity for a bit of study, if you fancy the challenge, ....... or find a good rigger.
CB

[zaphod]

I have done some of my own rigging work in the past, on smaller boats, and O am pretty familiar with rig tuning as some of the boats I raced on re-tuned the mast for different conditions. Even so, I would not step the mast on a 35ft boat without the aid of a rigger.

[johannes]

I browsed the pictures in my phone and found one that shows the shrouds on our boat neighbour's SO35. It is of little use to post it here, since you really have to have it in original size and zoom in to see the details. PM me if you want it in original size and I can e-mail it.

This SO 35 has an in-mast furling main, I don't know if the rig is different from a conventional mast. The picture shows that the lower shrouds are attached forward of the two other. It is not possible see which of the other two shrouds is the top and the intermediate.

However, the chainplate attachment is identical to the one on our SO 37, and we have a different arrangement: forward attachment point - top shroud, centre - lower, aft - intermediate.

It is quite possible that either of our set-ups, or both, are not according to the original set-up. We unstep and step every season, and someone may have switched at some point. To be frank I don't think it makes any big difference, since all shrouds attach at essentially the same point anyway.

Stepping and rigging a boat this size if not difficult to do yourself, but of course it helps a lot to do with someone with experience the first time. I have done it, or helped out, on different boats every year since I was a child so for me it is just part of the routine work every season.

[zaphod]

Apr 5, 2020 7:03:04 GMT johannes said:

I browsed the pictures in my phone and found one that shows the shrouds on our boat neighbour's SO35. It is of little use to post it here, since you really have to have it in original size and zoom in to see the details. PM me if you want it in original size and I can e-mail it.

This SO 35 has an in-mast furling main, I don't know if the rig is different from a conventional mast. The picture shows that the lower shrouds are attached forward of the two other. It is not possible see which of the other two shrouds is the top and the intermediate.

However, the chainplate attachment is identical to the one on our SO 37, and we have a different arrangement: forward attachment point - top shroud, centre - lower, aft - intermediate.

It is quite possible that either of our set-ups, or both, are not according to the original set-up. We unstep and step every season, and someone may have switched at some point. To be frank I don't think it makes any big difference, since all shrouds attach at essentially the same point anyway.

Stepping and rigging a boat this size if not difficult to do yourself, but of course it helps a lot to do with someone with experience the first time. I have done it, or helped out, on different boats every year since I was a child so for me it is just part of the routine work every season.

I guess if it is something you do every year it becomes routine. For me it is a rare occurence. My last boat was a 30 footer with a keel stepped mast and it was quite challenging to get the mast rigged correctly on the crane so that it slipped through the hole in the deck cleanly. I suppose a deck stepped mast is simpler. It is the rigging of the crane that is the riskiest thing. I am surprised they even let you do that yourself.

Don't you have to have your rig inspected for insurance purposes after you have stepped it?

[johannes]

No need for inspection, it is not something the insurance companies require. I guess the thinking is that since most boat owners unstep every year, they can keep a good track of the condition of the rig and replace parts as needed.

There are many ways to rig the crane, but I don't think it is particularly risky. The standard way is to rig a sling a bit above the mid point of the mast and attach it to the crane winch. It is easiest to be three persons: one operates the winch, one holds the foot of the mast, and one holds the forestay/furler. When the mast is in place, the person who held the forestay attaches the forestay and top shrouds, and your are done. The rest of the shrouds and tensioning can be done later.

Some people prefer to lift the mast using the spinnaker halyard, provided the crane is tall enough.

I usually leave the masthead instruments off until after stepping, and then climb the crane to attach them. The more daring/confident types leave them on when stepping.