Sadler 34 lower and cap chainplates

Cap shroud chainplates

The cap shroud chainplates on a Sadler 34 can be a source of persistent water leaks that are often blamed on the window. In our case water was gathering in the hanging locker, where it remains long-term because there is no drain hole. The job is straightforward but there are a couple of Sadler oddities.

Plate retention inside the boat

The plate is retained by a total of ten bolts, 17 mm spanner, five of which have nuts on them, bolted through the plywood bulkhead. This photo shows the five bolt heads from the saloon side, with nuts in the hanging locker.
  Inside the hanging locker are the five nuts and the other five bolt heads. The bolts pass through the bulkhead from the hanging locker into the ring frame. It is not possible to see what is inside this but I suspect there are nuts in there, retained in some way by resin. One of mine is not there and the bolt is not fully tightened.
On deck there are four smaller bolts, 13 mm spanner, that screw vertically into the deck. The aft pair go into something positive, nuts or aluminium plate, but the forward two only screw into GRP.

I attached the spinnaker halyard to the cradle beneath the boat and tightened it to its maximum. I then backed off the cap shroud bottle screw and removed the pin connecting it to the chainplate.


Removal and refitting
   Removal of the plate was perfectly straightforward, simply undoing all the bolts and pulling it out. The reason for the water leak was immediately obvious, a complete breakdown of whatever sealant was originally applied.
   The chainplate after removal.
   I rebedded the chainplate using PU40, very similar to Sikaflex 291 but half the price from Toolstation. Plenty applied to ensure full coverage. I tightened all the horizontal bolts before doing up the deck ones.

I was loaned a Loos gauge which I used before and after the job. I was pleased to find that the figures for cap and lower shrouds were just right using the simple method described in this section of the website at Cap shrouds are about 12% of breaking strain, lowers about 10%.

Lower shroud chainplates
    During this job it became apparent that the deck was commencing to bulge upwards slightly. The cause of this is that the lower chainplates, of ‘knee’ construction, are bending. Stronger versions of these plates are available from Mike Lucas. They are hidden from view in the saloon by GRP covers, held in with a sealant that has to be cut away.
 The chainplates and knees are then revealed. The chainplates are attached to the knees with nuts and bolts, as are their flanges to the deck.