Mainsheet Location Advice

[Lakesailor]

OK.
This morning I stepped the mast. I was going to video the procedure but it seemed to gather speed and suddenly it was too late to get the camera set-up.

I put the boom on and can now see where the mainsheet needs to be mounted in the boat. It falls about 9" behind the centerboard case, but as I have removable floor panels there I will need to attach it to the centreboard case instead.

There is a decorative grp cover over the centreboard casing. Calling it a flange is a bit dismissive as it was the support for the grp/ply sandwich which formed the original floor, which is now dispensed with.

I am guessing it is bonded along the top edge of the case on the inside and has some glass mat tabs along the bottom edge as well. There doesn't seem to be any movement between the cover and the case.
This shot is looking up under the rear of the flange

This is the point I propose to fix the fitting for the mainsheet.

I could also fit an easier to install loop on the bottom of the flange

I have stainless pads to back-up the fittings.

The question is: Will this be a suitable spot to mount the mainsheet?

Remember, this is not a 40ft racing yacht. It is a 17ft, ballasted open yacht which weighs about 500 kgs. Think of a slightly overgrown Wayfarer.
Yes the weight and ballast could mean there is more resistance to heeling so the mainsheet could be under more strain.
However it only has a total sail area of 150 sq ft.
Not a racing yacht.
The question is simply, would you expect the grp flange to be strong enough.
I think it will. My 13 ft clinker dinghy had a similar arrangement but is was merely fitted to the hog with wood screws!

 

[stevebrassett]

Looks strong enough to me.

So when it goes bang, you can console yourself with the thought that it would have broken for me, as well!

 

[Lakesailor]

Solidarity.

 

[Hypocacculus]

You don't want to fit a traveller then?

 

[Lakesailor]

Where?

The answer is, no. It's a daysailer for pottering about in. If I could have had the sail a bit flatter, or fuller in light airs, I don't lose any sleep by not doing so.

 

[stevebrassett]

Where?

The answer is, no. It's a daysailer for pottering about in. If I could have had the sail a bit flatter, or fuller in light airs, I don't lose any sleep by not doing so.

A decent kicker will give you most of that control on a small sail, anyway.

 

[oldbilbo]

I'd prefer to use the structural integrity of the transverse floor bearer immediately aft of the centreboard casing. The mainsheet load will impart a bending load on the c/b case, which may lead to 'trubl at mill'.

You could secure a bow shackle on the centreline or, using two of them a foot apart, provide an inverted 'V' mainsheet... or even provide a short traveller track along the top of the bearer by 'potting' securing bolts in thickened epoxy.

 

[Fantasie 19]

Would it be possible to reiforce the underside of the flange so as to spread the load more?? Thinking of a square ended "U" shaped piece of ply/metal bolted underneath the flange which you can then through bolt the main sheet eye to?

 

[Vara]

I'm with bilbo on location, but a horse or similar I feel is an unnecessary complication.

 

[mrming]

The first photo, yes - penny washers on the back - looks strong enough to me.

The second photo, no - wouldn't be comfortable with the upward load on the sticky-out-bit. I'd be worried it might break off.

Edit - just looked again at the fitting and the hole centres are probably too close for penny washers. I would move the fitting up a bit and have a slightly larger plywood backing pad behind to help spread the load a little more (assuming this wouldn't foul the centreboard).

 

[Lakesailor]

I'd prefer to use the structural integrity of the transverse floor bearer immediately aft of the centreboard casing. The mainsheet load will impart a bending load on the c/b case, which may lead to 'trubl at mill'.

You speak wisely old man.
The sideways loads could set up some unwanted effect. I may do as you suggest and bolt through the floor bearer which handily has a redwood "shelf" bonded to it. You can see it in this shot. It would only need a notch in the aft floor panel to accommodate it.

Virtual beer there. :very_drunk: (Drat, I should have thought of that myself. Too close to the problem)

In the meantime I've rigged it and checked everything is there. Bad news is there is no, and never has been, a kicking strap, which is more serious than not having a traveller.

I may have to fit one.

 

[stevebrassett]

Another thought. If the flange is in the right place for the mainsheet, you could always strengthen it with a "U"-shaped piece of wood or S/S underneath. Spread the load.

 

[sarabande]

is this luxury yacht going to be big enough for you to install

a) the Lakey patented steady cam mount

b) mast head light, strobe, white, passage past the ferry, for the use of ?

 

[Vara]

Can you trim that flange off...I hope we're still allowed to use the word 'flange'...it does look odd, and performs no useful function that I can see.

 

[prv]

Can you trim that flange off...I hope we're still allowed to use the word 'flange'...it does look odd, and performs no useful function that I can see.

I suggested that on the other thread, but I think Lakey thought I was referring to the whole moulding over the top of the centreboard case and he got a bit protective of it.

Either that or he really likes flanges.

Pete

 

[Vara]

Either that or he really likes flanges.

I believe his fondness for flanges has been noted many times on these fora.

 

[Lakesailor]

It's a pretty decent flange. Perhaps it doesn't come across too well in the pictures.
Sandgrounder popped in this afternoon and thought the boat was splendid. He made no comment on the flange.

In the pic above the flange was at it's most engorged. It has been trimmed since.

 

[Vara]

Ah yes, much better pic.
The whole project does look very good.

Oh did I mention that luff looks a bit slack.

How many years ago was it when we last had that conversation?

 

[stevebrassett]

In the pic above the flange was at it's most engorged. It has been trimmed since.

A trimmed flange is best.

How long before a thread about mainsheets gets pulled?

 

[ProDave]

Okay totally radical suggestion:

Move the main sheet attachment point to the end of the boom.

Bring the main sheet down to the transom.

This is what my little Frolic 18 does and it seems a good arrangement. The main sheet attaches to the same point as the back stay, which is a bridle that comes down either side of the transom bridging over the tiller.