Winter refit. Part 1 - Dismantling and keel-bolt removal

'Enfys' needs some fairly major maintenance and this has been in the planning for about a year. She had a busy 2018 sailing season with about twenty five separate trips and short voyages but with concerns about the condition of her sterntube we decided to carry out work over the winter 2018/2019.
She was brought by road to a yard in Pembroke Dock after mast was unstopped and all heavy and loose gear was removed.

Loaded up for short journey to Pembroke Dock

Sheeted-up to keep the weather out whilst work is carried out

Chocked up and sheeted-over the first job was to unbolt and lift out her engine and associated gear including fuel tank.  The inboard nuts of the two aftermost centreline ballast keel bolts are under the engine.

Engine out to give access for the work to come

The centreboard lifting wire was disconnected and pivot bolt removed - here it is after just four seasons' use showing the wasting caused by the fretting and movement of the 'plate in use.  This is an M24 bolt.

Centreplate pivot bolt - 50% gone after four seasons' use

The yacht was lifted off her centreplate to extract it and then set down on blocks high enough to enable the keel bolts to be driven out.

Finesse centreplate - this has been dispatched to be repaired and re-galvanised

Raised up on blocks

The heads of the nuts of the after two centreline bolts had almost completely dissolved away and their remains were chiselled away and the bolts driven out after the mortar encasing the heads in the ballast keel was broken out. Also removed were the first two forward of the centreboard slot. Their nuts were OK as they are rarely wet compared with the aft ones which are normally submerged in bilge water.
There is one further bolt right at the forward end of the ballast keel but its nut is hidden under the heads and it has been left for now.
All the bolts were intact and the forward ones were still dripping with tar from when they were first installed. The main area of wastage of these was in way of the main timber keel.  These centreline bolts are 3/4" BSW and range in length from 250mm to 290mm. (Going metric for the replacements!)

Forward keel bolts driven out - still covered in their original tar.

The next stage was to expose the inboard ends of the keel bolts alongside the centreboard case.  There are four of these each side but they are underneath the centreplate case upper part and capping so we had no option but to remove it all.  This casing needs attention though as there have been 'rusty weeps' seeping in through the lower part for years and this was only going to get worse with time.

A bit of dismantling of the galley unit and the companionway step was required to free the centreplate case sides and they were carefully unfastened. A replacement forward capping had been Sikaflexed and screwed to the forward face at sometime in an attempt to stem the seepage and the Sika sticks so well I had no choice but to chisel the capping to bits to get it off.

'Plate case forward capping had to be chiselled off

Most of the screws holding the cabin sole capping had to be drilled or broke off but eventually it was free to prise off.

Lower capping - evidence of minor weeping through the sealant

After removing some battens that had been added to the foot of the case and rows of screws and the copper through-fastenings the case sides were freed and removed. The original glue lines had long failed and the step joints were full of mud and crumbling sealant - no wonder she was leaking.

Centreplate case - starboard side. Circular scour is from lifting wire attachment point.

Plugs over the ballast keel bolts were identified and drilled and picked out. We had to take care to identify the ballast bolts as there are others between them which only fasten the centreboard case to the hog/keel and these were not to be disturbed.

The nuts of these bolts were drilled/chiselled away and all but two of these were able to be driven out but put up more of a fight than the centre bolts as they are much longer; up to 420mm. They are (or were when new) 5/8" diameter.

Nuts under the plugs were all badly corroded.

Two of them refused to give despite a serious beating; one is so wasted it just bent, the other moved a bit but is now solid. We plan to come back to this with a drilling machine to set up over these.

Two very stubborn bolts - resisting a serious beating

Now that there is nothing much holding the ballast keel on we put a temporary length of M12 threaded rod through two of the holes till the new bolts can be fitted.

Temporary studding installed and nutted-up