Building the Eun Mara "Skerry"

Fitting out - general

Eun Mara main

Given their complexity, I have put the bilge boards and bilge board cases on their own page.

Inwales ("shelf")
Floors
Foredeck framing
Aft deck framing
Berth framing
Bilgeboard case covers
Painting the cabin interior
Instruments

Inwales ("shelf")

After spending many days cleaning up the inside of the hull, including applying fillets to all the inside plank overlaps, the first actual construction work I undertook was of the inwales. I made these from three strips of ply, as I knew that this would easily take the curve of the shear. It ended up a little wider than the plans suggest, but I could see no problem with that.

Each inwale was formed on the boat, but not initially glued to the hull. When the three strips were glued together I removed the resulting roughly-formed inwales from the boat and faired the edge that would be the underside. (An interesting experience, trying to plane one side of a very springy curved 7m length of timber that really didn't want to stay in one place!) Once faired on the underside I glued them to the shear. As has often been said, you can never have too many clamps.

 

When the time came to fair the top of the inwales I found this 6 degree gauge very useful. The trick is to always keep it oriented perpendicular the the centreline of the boat, not to the sheer itself.

top

Floors

Next, I made station 2 bulkhead and then the floors. Each floor is laminated from three side-by-side pieces of walnut (my old 1981 packing cases again). Each hatch opening has a ply flange that will hold a rubber gasket which should (I hope!) form a watertight seal when the matching hatch cover is clamped down.

Note. At this time the floors fitted the hull reasonably well. I decided not to epoxy them in place until after I had cut the slots for the bilge board cases, as then I could remove the floors to make room to maneuver the power saw. However, after I had almost completed the BB cases I decided that it was time to epoxy the floors in place. Surprise! - some of them didn't fit very well at all. It wasn't a huge gap; maybe three millimetres at worst. I assume that when the slots were cut for the bilge board cases the garboard relaxed slightly (perhaps over time, as I spent several weeks working on the bilge boards and cases), creating the misfit. So, the moral might be either to epoxy the floors before cutting the slots or not to shape the floors until after the slots have been cut.

 

This shot shows the port chain-plate backing pad being glued between stations 3 and 4. The starboard one is already attached.

 

Of course, it's important to have those fillets thoroughly checked. Fortunately grandson Robbie was available to help out.

top

 

Foredeck framing

The mast beams are each made from two 18mm jarrah planks glued together. The result should be very strong.

 

These shots show details of the mast beam knees. The aft beam knee is smaller, as I think is suggested by the plans. As it's attached to the chain plate backing pad it should be quite sturdy.

 

I experimented a bit with choice of timber for the rest of the framing, as the frames won't be easily visible once the cabin is completed. The king plank is radiata pine, mainly because I had a conveniently sized piece at hand. The station 1 beam is "Tasmanian oak"- the quotes signifying that it neither comes from Tasmania nor is oak, just the local name for any of a variety of light-coloured eucalypts. Though strictly a hardwood, it is lightweight and easy to work, and strong if you get a good straight-grained piece. It's also modestly priced and readily available at our local hardware store. The forward hatch beam (just aft of the bulkhead) is Victorian ash (again, not necessarily from Victoria, and certainly not ash). It's from the same group of eucalypts but tends to be softer and lighter than the oak and, for me, not quite as easily available, so I'll probably stay with the oak.

Deviating slightly from the plans, I extended the king plank aft across the forward hatch beam. I'll cut out a section to take the samson post (see below).

The trusty block plane and spokeshave earned their keep here.

 

I cut out a step around 1.5cm into the inner stem to provide a seat for the king plank.

 

This shot shows (not very clearly) a lath extending from halfway along the king plank to the aft mast beam. It follows a slight curve, which is why I used the spokeshave as a weight to hold it down. I show this picture because it was not clear to me just what for-to-aft curve would be needed on the foredeck. The lath indicates the curve it will take on Skerry.

 

Here's the samson post being fabricated from four jarrah planks...

 

and here it is cleaned up and in place, nestled nicely in the gap I cut in the king plank.

Oops... I put together the forward hatch framing but forgot to allow for the curve on the cross-beam. Hence the thin strip which will be glued to the top surface and then faired off to match the deck curve.

All that is missing now are the short pieces to be fitted either side of the samson post. However, I'll leave them so I can remove the samson post until I have the foredeck pieces shaped.

top

 

Aft deck framing

Here's the station 8 bulkhead being offered up. (The small block on the keelson is lightly tacked in place just to stop the sheet sliding at the bottom.)

 

This picture shows the Stn.9 beam in place (but not yet glued or faired) and the mizzen mast box being offered up. The box is not yet glued together and a drainage tube has yet to be fitted.

top

 

Berth framing

My reading of the plans indicates 1/4" ply for the forward berth top, supported at the hull by side frames and centrally by a single fore-aft beam. As this is where you will stand to poke head and shoulders through the forward deck hatch (and as my beam is slightly narrower than the plans suggest) I felt that more bracing would not be a bad idea. Therefore I have supported the central beam by a 3/4" by 3.5" stanchion set crossways, which is wide enough also to support the inboard ends of two half-beams. The trade-off here is that the berth top will be made in two removable sections so that the space below can be used for storage, and I'm sure the extra framing will get in the way when stowing things.

The photo above shows the completed station 3 part-bulkhead, and the stanchion epoxied in place between it and the samson post. The rest of the framing is just tacked in place for now. I have used two sets of four cleats either side to support the berth top at the hull, as it was then relatively easy to adjust the bevels to cope with the changing angle of the planks.

The next step will be to epoxy in place everything except the forward end of the central beam, the samson post, and the cleats on the station 2 bulkhead. I'll defer these so I can remove the samson post when I come to fit the ply for the foredeck.

 

Here is the finished effect. I've added a 10mm wide jarrah trimming strip, the top of which is flush with the top surfaces of the berth tops. A second pair of cleats on the station 2 bulkhead form a pair of slots to secure the forward ends of the berth tops, while the aft ends are secured by the small 10mm wide turn buttons screwed into the trimming strip. (The trim is just screwed at present as I'll need to remove it to cut inserts when I fit the rails for the remaining berth framing.)

 

And some weeks later, here's the completed berth tops and flooring. The finger holes allow the sections to be lifted without too much damage to finger-nails.

 

These simple turnbuttons help stop the ply sections rattling around.

top

 

Bilgeboard case covers

The fitting of the covers for the tops of the BB cases is complicated (in my mind, anyway) by the fact the the part-bulkheads have to somehow fit over the top of the cases. From what I have seen of EMs "in the flesh" and from pictures, every builder has their own strategy to work around this.

 

I chose to epoxy the bottom of each bulkhead to the top of the BB case, and therefore made the covers in two sections, as shown in this image. Eventually the covers will need to have a watertight seal and so every edge of a cover needs something to press down on. Therefore just beneath the bulkhead I epoxied a 6mm thick piece of jarrah that protrudes either side sufficiently to give the cover something to make contact with. The insert is thin enough not to impede the raising of the bilgeboards.

 

If the forward end of the BB case is covered with a rectangular top then a narrow triangular gap is left between BB and berth edge that must somehow be filled.

 

Instead, I made the BB case cover a trapezoidal shape that also covers the triangular gap.

 

Here are the completed berth tops incorporating the BB case covers.

top

Painting the cabin interior

I thought that white paint would brighten the cabin. I sealed all surfaces with SenSeal, then applied two coats of Norglass undercoat followed by two coats of Norglass white (straight out of the tin - no flattener this time). The dark timber trim (jarrah or walnut) is varnished (after sealing). The flat surfaces just have the sealer on at the moment - I'm undecided how to finish them - probably varnish.

The hatch covers in the bulkhead have a layer of neoprene on the inside which I hope will form a waterproof seal against the inner flanges. (I'll find out the first time we start sinking!)

The pair of shelves above the berths is a design variation. I'd seen such things on other EMs and they looked useful.

 

top

Instruments

These are the transducers for depth (left) and speed. You can also see the extra wooden block that I added to take the sixth bolt for securing the two lead ballast sections.

 

top