Mast and rig choices for a pocket cruiser

[solarsea]

Hi folks,

I'm looking for a small sailboat and I've found that a local builder does a neat 15ft hull of the pocket cruisers variety. It's made of GPR and the sailing option includes a daggerboard with a box. It comes un-rigged with a deck-stepped mast receptacle and no compression post, although according to the builder the deck is reinforced to handle the loads.

The thing is, they don't do rigs so I have to source the mast, sails and rigging by myself. There's the silver lining and the cause of this thread. I'd like sailing the boat to be as leisurely as humanly possible. It will be a day sailer for protected and close to shore waters.

This naturally gets me thinking about a cat rig, with a lug or spritsail, or even a junk in some time. But then it has to have an un-stayed mast, which I guess means building it in such way that the mast is keel-stepped.

Please, do comment on. What kind of rig should I get, sail sizes, mast dimensions and material and so on ? I'm a software guy and even though I have an ICC license I know practically nothing about boats

Thanks!

Here's a few pictures of the hull, though in the motored variety.

p.s. I'm looking at a 15ft boat as that's the maximum length allowed here before mandatory registration and complex maritime legislations take over.

 

[PAR]

If this design was drawn up with a rig and is built to include the dagger case, then you should also find drawings for the sail plan, standing/running rigging and the rudder.

If the boat doesn't come with this information, you'd be best advised to look elsewhere. It's not that you can't hobble your way through, but it's completely unnecessary, given the design already should have these things. Simply put, you'll need fairly precise "centers" locations for the appropriate area, rigging hard point reinforcements, etc., all of which should have been done before the boat popped out of the mold.

 

[messabout]

Solarsea, Par has written words of wisdom. Find out why the builder does not provide the rig. Find out if he knows what he is doing as a matter of practical fact. Building a hull is one thing, accounting for all the variables is quite another.

As for a rig you could use a peak sprit or a sprit boom rig with shrouds and forestay. No problem there. But you need to marry the location of the rig to the center of lateral area of the boat if the rig is going to work well or at all....just as Par says.

If the boat has a dagger board does it also have a rudder?

 

[solarsea]

Gents, you are, indisputably, correct in your line of reasoning Though, if it wasn't for the lack of readily available sailing boats here I wouldn't have bothered to go the long way around.

This hull on the other side is quite affordable in local terms. The builder is situated on a riverside town and has been doing, for the better part of the last three decades or so, fishing boats to fulfill regional needs. The river has a strong current so most of their boats are used with engines or paddles. This, and the piss poor state of the economy here means that very few people purchase sail boats, and those that do usually have the means to get larger yachts and moor them in marinas.

I will try to get myself as much documentation as available on the hull and take it from there. I do have the feeling though that the boat might have been designed in a, let's say, artisan way Which isn't necessary a bad thing but then I'll have to figure the CoG, CoE and all the other variables experimentally to turn this into a a somewhat viable sailboat. Still, pricing considerations and lack of other options in that segment might make me go this route.

Aside from always wearing a life vest, what are the major things that I have to look in to ?

Regards,
Stan

 

[messabout]

That is a pretty little boat. It is not clear whether it has some bottom rocker. If the boat is sold primarily as a power boat then it may be a planeing boat that has no aft rocker.

A sail boat needs to have a bottom profile that lets the transom clear the water. Thus, the bottom will curve upward in the back end. It is true that you can sail a powerboat but it will be a poor performer.

The boat, as pretty as it is, I would not recommend it as a sailing boat. It is going to be heavy and that is not good for a small sailboat unless it is of a ballasted sailing design. The dagger board case or centerboard case is going to fall right where you do not want it to be. Somewhere near the middle of the boat, it may intrude into the cabin space.

If there are some of those boats running around in the river you can see whether they can plane by simply watching them. A boat like that would need a 15 or 20 Kw motor to make it go well. If it is seen to skim across the water at some speed, then it is not what you want as a sailboat.

Sorry to sound like the voice of doom.

 

[solarsea]

I have managed to obtain a bit more information about the boat They have plans (I've seen photos of it), including a rudder, daggerboard and a basic cat plan - a bermudian sail with a boom, a stayed mast with a forestay, aft of mast side stays and no backstay. The boom has a vang-like arrangement, though only with blocks and a single mainsheet. The sail is of a modest size, approximately 6 sq. m.

However, those plans are for the open version of the boat, with the cuddy being a later development. The builder can either reinforce the cabin top to allow for a stayed mast of place a collar/mast partners for an unstayed one.

A couple of questions follow

- Assuming that the cabin is a bolt on top addon, the center of lateral resistance in the water should not change ? (except forward tipping due to the cabin's weight)

- I'd like to have a balanced lug. What else should I look at besides matching its CoE with the likely CoE of the bermudian sail in the plan ? Righting moment will be a bit higher, due to the height of the cabin and the sail being placed higher with respect to the center of mass of the boat.

- What would be a practical length and diameter for a wooden unstayed mast? Of course, this is related to its height and the bury depth. I plan to start with an opening of 15 to 20cm and then experiment, this should provide plenty of safety margin seeing how must more larger, junk rigged vessels have a mast diameter of 25cm at the parners.

Regards,
Stan