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Apologies for the late post. I normally attempt to publish on thursdays, but was counting on posting another video montage. However, i’m having technical issues with the video renderer, obliging me to write after all at the last moment.


The next few months at Guayama i spent changing the rig and making the boat livable.

A lot of the nativos don’t have floorboards; you just walk on the ballast itself, but the Oasis had floorboards fitted some years after being launched to make tacking faster. This is because when you tack the rail meat all leap down into the hole along with their sandbags and then climb out on the new windward side, but it is a long way up. You have to first heave the sandbag onto the deck and then climb out yourself, and this is easier if the hole is not so deep.

So i removed the floorboards and cut them such that they would fit just over the top of the ballast, for more living space, lowering it by 30 cM. Forward and aft there were no floorboards so i made them. The aft floorboards would become our bunk.


The blue floorboards are the original floorboards, recut to fit lower down and further forward. The paint on the hull shows where the floorboards used to be.

The Oasis is the only Puertorican Nativo which has the mast going through the deck , in front of the opening in the deck. All the others have the partners inside the hole, usually with a strap going across the aft side of the mast. This makes stepping the mast a lot easier, but would have forced me to rebuild the deck aft of the mast before being able to build up a cabin. The reason for this is that it is not good engineering to have the mast go through the cabin top, as it is much weaker than going through the deck which is an uninterrupted span across the boat.

As it was all i had to do was build up the cabin sides around the existing deck aperture and screw and glue to the existing coamings.

cabin sides

Cabin sides fixed to coamings

After this i was keen to not have beams eating into the little height i had so i made the rooftop out of three layers of 6 mM plywood glued and screwed together over three forms which i subsequently removed. These defined a variable crown rooftop increasing towards the stern significantly.

Building cabin trunk

Moulds for cabin roof.

Using this constuction method enabled me to build a rooftop with no beams at all and quite strong enough. Some may wonder why i didn’t just make the cabintop higher; the reason is because raising the boom makes you lose the most valuable part of the sail, the part that is low down, contributing lift with very little heeling moment. As is, i only raised the boom 25 cM at the gooseneck, although much more at the after end so the boom would not hit the water so easily.

As soon as the cabin was made the boat became an oven, so i quickly made two hatches to re establish the proper ventilation. I also painted over the grey deck paint which would get so hot as to be painful on the feet, with pure white. For boats in the tropics, there is really only one acceptable color; white. I know the glare is something awful, but it is unavoidable, as that is exactly the desired effect; reflect the incident sunlight back away, to keep the boat tolerably cool. The equation is very simple; the less glare, the more heat, and vice-versa and there is really no way around it. Just good sunglasses.

aft deck

My wife giving a hand painting the new hatch.

For unstepping the mast i used the mast of a sailboat that was sunk on the other side of the bay, heeled over at a sharp angle. I climbed up this mast, which was quite terrifying i must admit, and set up my block and tackle. Then by anchoring the Oasis with four anchors under the top of this makeshift crane i could pull my mast straight up and out of its hole. Unfortunately, the mast was stuck fast so hard that no amount of force would budge it. So i cut the mast near the heel and dealt with the heel later.

Of course all the hardware, being stainless steel in aluminium was welded tight. Very few screws came out intact, instead i broke them off, and some had to just be ground down. After leaving the mast as a bare pole, i cut 2.5 M off each end, leaving me the fattest part of the mast at the height of the partners. Oddly enough the fattest part had been a couple meters above deck.

For the ends i laminated up wooden plugs, carefully sculpted for a perfect fit. At the heel, a tenon sticks out that fits into a slot on the mast step. The top of this is sloped and liberally sealed with epoxy. A small hole allows any water to drain out of the mast. At the top the plug projects beyond the aluminium so i could shape the step that take the peak halyard and a sheave for the topsail halyard. Both of these were then glued and screwed in place.

rough plug

Building up the plug for the mast end.

mast plug shaped

Roughly shaped and fitted ready to be glued in place.

Mast end plug in place

The first step will take the peak halyard. The sheave slot will be for the topsail halyard. The topmost step is for the spinnaker halyard.

Mast end plug shaped

Shaped and sealed.

Mast end plug finished

Blends right in with the aluminium!

In all i removed almost 60 kg of weight from the top of the rig. Selling the aluminium and stainless paid for the few bits of new hardware i needed, namely the new norseman compression cones. The gaff added less than 12 kg to the top of the rig. So i think that demonstrates the fallacy of gaff rigs being top heavy! And it is not true to say that that is due to actually having cut down on sail area, because with the topsail, the boat has almost the same sail area as originally and the topsail yard will only add another 10 kg or so, and that is weight that  is there only when needed, and that in light wind.
I think this last point is extremely important to understand; marconi rigs reef only the fabric. All the spars are fixed. On a gaff rig the topsail yard is taken down when not in use, and the gaff itself gets succesively lower with each reef leaving a bare minimum of weight and windage up when the going gets tough.

Sewing a mast boot

Sewing up the mast boot with some black denim.

Mast boot

Just needs a coat of paint – make that 7 – and no more water come in.

mast boot

The finished boot

Another change was i eliminated the two internal halyards, routing everything outside of the mast and taking care to seal the mast up entirely. Although this adds a bit of windage it is not much in terms of total percentage and it makes for one less thing that can go wrong. Also it makes the boat almost uncapsizable; i did some righting moment estimates and with that kind of buoyant volume as soon as they go underwater the boat’s righting moment almost doubles, which is a great safety advantage, especially if you think about how unlikely it would be for a capsized boat to right itself with a hollow mast that is all flooded full of water..

Then i recut the sails using a favorite time saver; contact cement. To save effort i recycled all the corner pieces by cutting them out whole and transposing them to their new positions.

Checking the new sail plan

Raising the sail folded along the cut lines and viewing from afar allowed to double check that the measurements i had determined on the drawing board would indeed be correct.

Re-cutting a sail

A covered basketball court made an ideal place to work on the sails. All edges and corners were preserved and re-attached in their new positions saving an immense amount of work and money.

The boom also got cut by 2.5 M down from the original 11.3 m to 8.8 M. I also modified the gooseneck to allow the boom to be raised to an angle of around 60 degrees so that it could be used as a crane. This rounded out the boat well for earning money later as a “floating workshop” complete with generator, a large collection of woodworking tools and two cranes (the gaff and the boom) to move heavy objects or step-unstep masts. Not having a cockpit means that the entire stern of the boat is flat and uncluttered for working easily.

Oasis mast down

Oasis with mast down.
on one side a boat i was doing work on, on the other a boat i was lookin after and where we also temporarily lived.

Inside i made a galley that uses the entire beam of the boat under the companionway hatch (to vent out the heat and also so i would get standing headroom when cooking) with gymbaled stove and an adjustable angle cutting board. On a cruising boat the galley is the most important area to get right. Cooking at sea is always challenging so every effort should be made to ensure that the galley makes those daily hours as easy as possible.

Forward of this and up to the mast is the cargo area on either side all the way up to the deckhead, leaving a passage in the middle. This gives a good distribution of weight out of the ends of the boat.

The advantage with this sort of boat is that the modifications can be made rough and ready and it doesn’t clash with what is already there. if this were a fancy yacht with delicate wood trim etc, to keep the modifications on the level would require considerably more time and effort.

Supper after work

Christina makes us supper in the neighbour’s boat.