If Gunboats Can Have This, Why Can’t I?

[GRIT]

Hi Jmh2002. It's always nice to hear from you.

Thanks for your interest. Thus far, we've not had a need for a preventer. The track is 15 feet wide, and if I put the mainsail to the end, I must tighten on the sheet, to prevent it from laying on the shrouds. As a rule, we don't lay the main on the shrouds.

We don't yet have a spinnaker, so going deep downwind in less than 20 knots, we set up the main to feed the code 0, so the main is within a metre of centre. This will normally keep us above 50% of windspeed, depending on how deep we go.

Above 20 knots of wind, dead downwind, depending if the mainsail is full or reefed, we do between 8 and 10 knots. I hope a spinnaker will improve those numbers substantially.

Without a spinnaker, we have a bit of a dead zone between 135 and 180 degrees, where the jib is useless, and we have no proper forward sail. That situation will hopefully be remedied this fall.

Cheers.
Paul.

[jmh2002]

Originally Posted by GRIT

Hi Jmh2002. It's always nice to hear from you.

Thanks for your interest. Thus far, we've not had a need for a preventer. The track is 15 feet wide, and if I put the mainsail to the end, I must tighten on the sheet, to prevent it from laying on the shrouds...

Always a pleasure

Yes certainly just how far the Mainsail can be eased vs where the Traveller stops is a consideration on a cat too.

On the Gunboat that Chotu posted (posted below again) the Traveller could go all the way towards the deck edge if necessary - is GRIT like that too, I don't remember?.

But of course many other cats have break in the aft crossbeam there and a walkway down to the transom, shortening the traveller length by probably at least 1m / 3ft each side.

Do your Traveller control lines run to the forward cockpit along with the Mainsheet so that everything can be handled from there?

Now that I think of it maybe you have a line drive for your traveller (or maybe I'm thinking of another boat... )?


Cheers

[GRIT]

Hi Jmh.

Yes, we have a line driver, and reversible electric winch for the main sheet. A joystick controls the lot. Left or right, moves the boom left, or right. Forward sheets out, and aft sheets in. It's quite nice, and my wife loves being able to adjust the mainsail on her own.

The track is just shy of the insides of the hulls, but ad the twist in the main, and it's easy to get it to sit on the shrouds. So we're careful about that.

Cheers.
Paul.

[jmh2002]

Ah good, I remembered correctly

I think your setup is really a no brainer, especially with a forward cockpit.

And the A-frame mainsheet system would be an enormous pita by comparison!

It's only saving grace is less weight and less cost.

I may be wrong but I'm guessing the Gunboat went with that setup to reduce the clutter aft, and leave space for the davit winches and lifting the dinghy since it's a guest cockpit rather than a sailing cockpit and the layout doesn't really leave a lot of space for both.

Personally I think many of the Gunboat and Atlantic style cats have too small aft cockpits, but it's obviously a conscious choice to prioritise interior space and that's somehow understandable.

But given that the rest of a Gunboat is not exactly budget conscious I think I would have chosen something similar to your setup instead with regarding to the Mainsheet and Traveller.

That would be even less clutter again aft, although space is still needed for handling the dinghy.

[GRIT]

To Chotu's question. I don't see any reason you can't set your boat up like that. It's going to be lighter, and faster to install too. A padeye on each end of the beam, and you're ready to hook up your blocks.

Just because it's not my preference, doesn't mean it's not right. If it's right for you, I say go for it. Easily sourced parts, and an easy installation, are two big plusses.

Of course we love our setup, but it's not going to be for everyone. Many things we did to our boat were for ease of use, while pushing on the budget envelope a bit. Still, we have no regrets, and have a very easily handled boat.

As for the Gunboats with an unlimited budget. I do wonder why they didn't install internal winches for the dinghies. It's not like the total of 35 or 40kg is going to break the bank on a boat that size. That looks like it's over 60 feet.

Cheers.
Paul.

[jmh2002]

^^^ I agree with all those points too

Originally Posted by GRIT

To Chotu's question. I don't see any reason you can't set your boat up like that. It's going to be lighter, and faster to install too. A padeye on each end of the beam, and you're ready to hook up your blocks.

Yes, light, simple, cheaper, and faster install vs maybe not the 'perfect' setup.

Also in respect to Chotu's situation if as I expect it's about getting the boat working and sailing then of course this is an easy option to consider.

Let's also remember that it also doesn't preclude upgrading to a full Traveller based system in the future if that is deemed necessary.

[Steamer]

Originally Posted by Chotu

Exactly. I’m really attracted to the simplicity of it.

A) Simplicity to have it done and costs savings are the only reasons to accept this setup.

B) Having traveller makes life much-much easier particularly if You sail single-handed.

This is from personal experience sailing with a) and b) systems.

[goboatingnow]

If you have a rigid vang , why bother with a traveller anyway

[Rucksta]

Originally Posted by goboatingnow

If you have a rigid vang , why bother with a traveller anyway

1. centre or over centre the boom in light air.
2. depower the main in gusts with auto adjust leech tension
3. facilitate tacking - use or emulate windward sheeting car
4. control boom during gybes
5. really effective way to donate multiple boat $$ to Harken.

On my aft cockpit mono the traveller keeps the pit crew away from the back of the boat where the serious work is done

[graypenguin]

I have a 34' Catalac that has a boom with no attachments on it. The previous owner bought it with no mast or boom and was in the process of re-rigging it. I have two pad eye type attachments on the cabin top. I was hoping to utilize the pad eyes but as not sure how. Maybe this type of system was on it before it was demasted. I am going to try this type of system out. My question is, What size line should I use for a cat this size? the boom is about 13ft long.

[Rucksta]

https://www.harken.co.uk/content.aspx?id=9094

Mainsheet loading calculator from Harken.
Calculate the load then find a sheet to handle calculated load.
Make sure the attachment points and blocks are up to the load.
Note that load increases exponentially with wind speed.

Anything smaller than 3/8" can get hard to handle.

[Chrisatlantic]

Graypenguin, 3/8” would be good in dyneema core (even 5/16” dyneema should be strong enough) or probably 7/16” in polyester. Assuming you’re going to a self tailing winch with it, make sure the size you choose works well in the self tailer - smaller lines like 5/16 or 3/8 may not work in some.

[Chrisatlantic]

Re the OP question - the split mainsheet works fine. Upwind/close reaching, position boom laterally with windward sheet then tension the leech with the leeward sheet. Assuming low stretch line and attachment of pad eyes on aft cockpit coaming near inboard edge of each hull there will be minimal lateral movement when trimming the leeward sheet to get the desired leech tension/twist. I don’t think there’s any issue at all with achieving a precise and consistent trim and it’s really nice not to have any back and forth movement of the boom in waves, much quieter.

For tacking, you may need to ease the old leeward sheet a bit as you’re falling off coming out of the tack depending on your boat's balance and rudder authority. Then re-adjustment may be needed once you’re back up to speed and that I would say is the negative of this system.

Jumping the leeward sheet outboard to a padeye at the rail (and probably a little farther forward) after bearing away should be straightforward, just ease the leeward sheet a bit (if even necessary), ease the weather sheet to position the boom laterally and move the leeward deck block to the outboard pad eye and then trim on the leeward sheet to desired leech twist. Like Grit, we keep the main off the leeward shrouds on my Atlantic 55 so when the boom is very far off the centerline we need to have some reasonable leech tension. Though on my boat I still have a traditional traveller with preventers rigged on both sides, if I were doing it over I’d probably do the split sheet setup.

One last thought is mainsheet dump. You’re basically going to have to dump the weather sheet. Usually, that would be adequate by itself. Probably the only time it wouldn’t be would be when the boom is positioned almost over or just outboard of the leeward pad eye, in that case you’d have to dump the leeward sheet too. Something to think about.

Disclaimer - despite my username, I am not CW

[Chotu]

Hmmmm. Lots to consider here. I’m feeling lazy so I’m attracted to Grit’s solution.

[Sand crab]

Originally Posted by Chrisatlantic

Disclaimer - despite my username, I am not CW

That's a relief because all or most of his designs use a traveler.
Some have the traveler on the coach roof with a midish boom attachment which is unusual.