The blog will now be devoted not to boat building but to my 82-year-old Vertue, Sally II, now undergoing a well needed refit at Johnson & Loftus in Ullapool (and gliding...)

Wednesday, 6 July 2011

Back to Work

Gun punt gone; Nutshell pram gone; loch boat gone, so a few days off were just what I needed before work began on the Tammie Norrie.
And do you know, it took me a day of head scratching to remember how it all goes together. Thing is every time I build a boat I look to ways of doing things a little differently, which is one of the joys of building from scratch. Iain Oughtred's plans are superb, but they don't really go into much detail about how to build in traditional clinker, and, believe me, there are differences, beginning with the centreline.
In a ply/epoxy boat it's all planked onto the keelson or hog, and the (outer) keel gets plonked on at the end. In a traditional boat the keelson/keel assembly forms a T shape, and the rabbet is worked into where the two join. And it all gets a little interesting where it joins the stem, which can be made solid or laminated in two parts, just like its ply counterpart.

And there are so many ways to make that vital join. I was taught to half joint the inner stem (apron) to the outer keel, and blend the keelson into the apron, with a knee to strengthen the join, but in Iain's plans the apron sits on top of the keelson, making a sandwich with the outer keel. Too complicated to explain, and my head was spinning by the time I figured out (or remembered) how it all went together. Best to draw it (which I did with the centreboard case (above).

In the end I went for a solid one piece stem, which will mean chiselling out a rabbet, rather than forming the rabbet by slapping the outer stem onto the apron (after planing the protruding planks flush). It's always been a problem lining up the hood end screws in a two-part laminated stem. I am sure there's a clever trick to scribe a screw line on the ouside of the plank by following the fore side of the apron, using some contraption that straddles the excess plank end, but I've not discovered it, and thus every so often a screw gets a touch too close to the edge, or too far away, resulting not in that elegant curve of screws but a bit of a detour.

Not so with a rabbet. You can get those screws in bang where you want them, although fitting the plank ends is not quite as easy as simply planing them flush.

All pretty esoteric boat building stuff, for which I apologise.

But you can see at least what a stem/keel joint looks like as drawn by Mr Oughtred. Mine will have the same profile but not the same construction. Which means next time I build a boat I'll spend another day trying to remember what I did the time before.

PS And those monetary calculations are before the carriage was added (stuff from Robbins, if you must know...)

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