Resealing chainplates. Any order to loosening shrouds?

[fredrussell]

Need to reseal both chainplates. I’ll tension a halyard or two from masthead to toerail/cleats/winch etc but is there any order of shroud loosening? It’s a twin spreader fractional rig, keel stepped mast.
Would it be better to run halyards to port and starboard toerails and then loosen both sides of shrouds gradually to keep mast straight-ish and then reseal both chainplates?
…or is it preferable to just run halyard(s) to one side and deal with that chainplate, then retighten shrouds on that side before transferring my attention to other side’s chainplate?
I have a Loos Gauge, boat will be afloat during all this but in a well sheltered ‘cut’, and obviously I won’t be doing this in a F9.

 

[Concerto]

The order to release tension is not critical. Best to release a set number of turns on all shrouds, then when retensioning just do the same number of turns to tension. This is useful for those who do not have access to a rigging tension guage, but you can use your guage to fine tune the rig. After the rig is no longer under tension and supported by halyards, reseat the chainplates.

 

[vyv_cox]

When I rebedded a cap shroud on my single spreader rig I loosened it after tying halyards to the cradle (ashore). The mast bent a little but was returned to straight when the shroud was retensioned. Full write-up here Sadler 34 lower and cap chainplates

 

[dankilb]

If you’re doing all of them, doesn’t it make sense to loosen and work on (mirror/opposite) pairs? (Or does that go without saying?!)

 

[fredrussell]

Thanks all. Already viewed your how-to Vyv, very good. Dan, there’s only one chainplate each side of mast that all shrouds that side attach to.

 

[dankilb]

Dan, there’s only one chainplate each side of mast that all shrouds that side attach to.

Ah! We have three (so three times the leaks and by the looks of some of the welds now, soon to be three times the fabrication! ?)

 

[john_morris_uk]

Which bit loosened first doesn’t matter half as much as sealing them properly. The only technique I’ve found that’s long lasting leak free is to make sure you don’t tighten them up to squeeze all the sealant out when you re-bed them. Tighten them down until there’s a mm or three of sealant still underneath. Letthe sealant go off to form a gasket and then cinch the chai plate up tight the next day.
If you don’t do it this way, the sealant is all squidged out and the tiniest bit of movement of the chainplate (which WILL occur) causes a leak.
All IMHO of course.

 

[fredrussell]

Sounds like a good method John, I’ll do that.

 

[pandos]

As an aside.... I saw on a YouTube recently where the owners placed squares of fiberglass about 12mm thick and about 100mm square , with slots cut in them, down over the chain plates, and epoxied onto the deck, so that water on the deck would never be able to leak through the slots, and to provide better anchorage for the screws fixing the cover plates...