Repair to merlin hog

[merlinchris]

I am currently restoring a 1961 merlin. there is a previous repair to the transom/keel/hog due I assume to it being stord proped up and transom resting in water. Transom and keel are ok however the hog has suffered further rot and a piece needs replacing, approx from transom 6-9" forwards. The question is what is the best technique to create a horizontal scarf joint between the new wood and the existing sound hog.
Thanks

[Ed]

photos would help tons

eib

[Rupert]

Very sharp chisels.

[merlinchris]

here are some photos. Anticipate removing the knee to access the hog (replacing after). Wood between knee and hole in hog is not sound. You can see the original repair with vertical scarfe of of wood into the hog.

Interested in knowing the correct technique to create a scarfe joint between sound original hog and the replacement.

All help gratefully received.

[Garry R]

Definitely remove the knee, bearing in mind that there will be a screw coming through the hog holding it in place too. This is likely to be under the keel so I suggest that you just lever the knee off very carefully once all the "visible" screws have been removed - by that I mean the screws through the transom and the obvious one at the forward end of the knee. This will mean that you won't have to remove the keelband and keel to get at it. I would be inclined to cut that screw off flush anyhow then remove the rotten piece you are going to replace as far forward as you need to go to get back to solid wood. A clever way if you can do it would be to undercut the original hog (not easy getting angles and lengths correct as you have to slide the piece in from the side so sharp chisels are 100% correct Rupert) so the joint prevents the new insert from pulling upwards. Then make sure the keel underneath is completely clear of old glue and you should be able to epoxy the new insert in place with a screw or two down into the keel remembering to position them where the knee screw won't interfere!! Then epoxy the knee back, screwed tightly down again clean joint (and on the transom) and that should hold it. A little fillet of epoxy along the knee/hog joint wouldn't do any harm either. Hope this helps. I think that's how I did it on Ocean Wildcat (1728).

[Rupert]

One thing to look out for is whether the rot has travelled up inside the hog further than it has on the outside. One boat I was mending had a 2" rot patch showing, but the rot had almost hollowed out the hog for a good foot beyond that. If it has gone further than you thought, just comfort yourself with the thought that it is as easy to replace a slightly longer piece of wood as it is a short one. Easier, sometimes, as you'd be working further from the cramped bit round the transom.

[Ancient Geek]

I cannot add to Garry and the others in terms of rapair/replacement but something that even the beat yach builders seem to overlook is total drainage of water there is evidence in this picture of an attempt to get better drainage clinker hulls are especially suseptible (Prevention is better than cure!) but all dinghy hulls or keelboats with drain bungs no matter how cleverly they are drilled especially inside bulheads, the solution I have adopted and forced on boatbuilders too is to put the boat into drain/store position and tip in enough (2 pack preferably) varnish until it trickles out of the drain hole or off the lands. Once hardened (Hence preference for two pack!) it will ensure no water fails to drain. Providing you remember to remove the bungs and of course put them back in before putting the yot in the water!

[jpa_wfsc]

A MkIX Proctor I had for a while, looked totally sound. But the boat had been coated inside and out with epoxy. The transom was thus composed of about 0.5 mm walls of cellulose-reinforced plastic, with the centre of the composite structure composed of...



mush.



It was not very strong!

[Ancient Geek]

I was in no way suggesting that the treatment I proposed to a

sound

boat would add strength, it is merely a profilactic to water failing to drain totally and thus providing rot potential.

[Garry R]

A guy in the dinghy park beside me over the last two years had a Miracle dinghy and used the quite effective bit of cloth in the drain holes for getting rid of that last bit of water. Capillary action and the drying of the rags from the outside kept the transom area free of lying water.