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Geftb
10-01-2018, 08:33 AM
Greetings all!
Several months ago I purchased (what I think to be) a lovely 35 ft Ferro/ply/glass decks fashioned from the lines of Victorians "Couta Boat" (http://arhv.anmm.gov.au/en/collections/details/34280/the-couta-boat) made famous for racing back through "The Rip" and Bass Straight outside
Port Philip bay.
She was home built by Theo Lewis, a cray fisherman from Portland Victoria over a period of 14 years from 1986-2000 launch day. There was a whole bunch of Ferro boats built in Portland in the 70's so much so they had the Portland troweling crew who would turn up on trowel day and get it all done in a fine and well rehearsed rhythm. Comet was one of the last boat built of Ferro in the area, so I'm told.
Sadly, Theo passed not long after launch. She was purchased from him by his cousin Bruce whom living 2 hours away and being busy on his large farm didn't get to use her much at all.
So, she has largely sat there for all these years. A couple of trips to Port Fairy for a haul out and that's about it.

Ther's some brief history on her and a few photos. A couple of recent and some from Theo's time.
2379923800

I have a bunch of things I would like to do, but lets forget about all them for the moment and concentrate on the mast. As you can see its a Bermudian mast with a Gaff Rig. I'm guessing he scored it for free at the time? Theo has fashioned up a saddle to suit, which when it speaks to me says, "im going to jam just when you don't want me to". Plus its deck stepped, which I'm not particularly fond of. Being a renovation carpenter I have a whole pile of Oregon/Douglas Fir and I could piece together the tools, skills and will power to make up a Birdsmouth mast essentially following the rig that's there for height and placement. What I don't know and would like to put the question out there is mast diameter. The current mast is 11.5 meters/38ft high from deck level. Speaking to a local boat builder here he seemed to think 165mm/6.5 inch would be sufficient. It seemed light to me. I'm thinking closer to 178mm/7 inches. But what would I know really. If I could draw on some experience here it would be very much appreciated!

Reasons for replacing the mast:
1, Standing rigging is near on 20 years stainless steel, so that needs to be done anyway.
2, I would feel a whole lot better it being keel stepped. A few days work to change some interior but no biggie.
3, Proper saddle or jaws so as to help prevent jamming.

Boat is 35 ft, 11ft beam, 4 ft draft with a 4 ft dagger board.

Cheers Steve

DeniseO30
10-01-2018, 11:16 AM
Ferro seems to put off many .. but aside from that.. no need to to go through all that trouble just to build a keel stepped mast. If the compression post is up to the task you should be good to go.

wizbang 13
10-01-2018, 11:54 AM
Do you intend to make her a gaffer or get a bermudian main?

It's your "essentially follow the rig that's there" part has me wondering.The gaff main on that mast is....just wrong.
She appears to be a fat and full vessel,one that could carry a proper gaff rig.
Plenty fine lookin.
bruce

Geftb
10-01-2018, 02:29 PM
Definitely gaff, the mast is too far forward for Bermudian and there is a dagger board right behind it. Everything has been worked out for it to be gaff. I think he had run out of money towards the end. The sails are a mix of whatever he could find from other boats. There are 2 winches, no cleats. Its never really been sailed but the price was right. The rig current needs a lot of work anyway it's not just a jump on and sail away, so I'm happy to put a new mast in.
Anyone know how I should calculate the mast diameter?

DeniseO30
10-01-2018, 02:45 PM
Definitely gaff, the mast is too far forward for Bermudian and there is a dagger board right behind it. Everything has been worked out for it to be gaff. I think he had run out of money towards the end. The sails are a mix of whatever he could find from other boats. There are 2 winches, no cleats. Its never really been sailed but the price was right. The rig current needs a lot of work anyway it's not just a jump on and sail away, so I'm happy to put a new mast in.
Anyone know how I should calculate the mast diameter?Depending where you're located, up in Massachusetts there is a marine consignment store they have all kinds of aluminum masts and booms. They can be found on eBay and there's a place in Florida also.

There is probably thousands of aluminum rigs laying around because so many boats have been lost to storms. But you seem hell-bent on building mast and that's okay :)

Mast Building & rig engineering may not necessarily fall within the skill set of many boat builders. I know I would not be comfortable designing a sailing rig without consulting with a professional in that area of expertise

He maybe had bridges to go under, could be why the boat is the way it is.

skaraborgcraft
10-01-2018, 03:39 PM
Mike Peyton of ferro boat fame in the UK, had a similar rig, he put a permenent topsail on the gaff, and if i recall, the whole sail was raised by the topsail head. Mast was also tabernacle mounted. I believe it was one of his last "Touchstone" boats. I think the build got a lot of coverage back in the day in Practical Boat Owner mag.

wizbang 13
10-01-2018, 03:49 PM
My 34'gaffer has an 8 and a half inch mast.
It looks oversized at the dock.
It looks just right in an offshore gale.
What's the diameter of local telephone poles?
More seriously, what kind of sailing do you plan?
Sporty day sailing or ocean cruising?

Geftb
10-01-2018, 03:58 PM
Thank you Bruce. These are the details I'm looking for. The Bass Straight is my home sailing grounds so it has to be strong. Essentially I want it set up as a live aboard. This means crossing oceans. A deck stepped aluminium gaff rigged boat... I won't sleep right. I want it to be strong but being a cutter rig she will go somewhat higher than Your ketch. So weight aloft may come into play at 8and a half? That's a big mast!

wizbang 13
10-01-2018, 04:11 PM
Yes, my mast is about 1000 pounds. My boat is SUPPOSE to sail on her ear.
The spar does not necessarily need to be taller for a cutter than a ketch, your boom will be longer.(of course, the longer the boom, the higher peaked the gaff...the smaller the topsl.)
If you can build a nice bird thingy spar,by all means,consider it. Its going to want solid blocking at the deck and where the shrouds go, so you may have a water pocket issue. But with epoxy and some common sense , things can be figured out.
I am totally on board with a keel stepped mast for offshore. In real life, a popped shroud or a missed gybe while half asleep at night, this is where that extra security pays off.
I's there more info on your design? Is she a one off? Is there a bona fide sail plan somewhere?

Geftb
10-01-2018, 04:15 PM
Hi Skaraborg, I don't know what a touchstone boat is sorry.
This mast doesn't have a tabernacle. I have given it a lot of thought to put a tabernacle on there and be done with it... but is it strong enough for a gaffer? I have read through Zuris thread on converting to gaff rig ketch. All the comments from experienced gaff rig sailors had the common opinion is to keel step the mast. This make good sense to me.

Geftb
10-01-2018, 04:19 PM
She is a one off. I don't have a sail plan but have all the dimensions. I can draw up what I have tonight and post a photo. Unfortunately I have to go and do that silly work stuff for the next ten hours.
Chat soon. Cheers steve

Phil Y
10-01-2018, 04:22 PM
I'd go more like 7 than 6. But I don't know anything. Couta boats tend to have been optimised for bay racing so looking at what's around in Port Philip bay may not be helpful. Except to look at them and go a bit bigger.


Sent from my iPhone using Tapatalk

Geftb
10-01-2018, 04:49 PM
I just tried to post a photo twice and can't see the post from my end. If others can my apologies for triple post.
At this stage I'm thinking 7.5 inch Phil. There is a 50 ft timber yach next to mine in the yard and it has a mast of 8.5 inch.

Hallam
10-01-2018, 05:35 PM
That's a great looking boat you have there Steve. Portland is my home town but living on the Mornington Peninsula now. I have a very similar hull 30 ft long and am happy to talk couta boat details.
The mast of a couta boat will be as tall above deck as the boat is long. I'm working on my 30 ft mast at the moment. It is deck stepped in a tabernacle. When i find pics i will post them although there are a few in my thread about Warana, but Many pics went AWOL because of photobucket:

http://forum.woodenboat.com/showthread.php?181189-Warana-11-Blairgowrie-Victoria

My general rule since buying my boat to keep costs down is to only change things on the boat that really need it. My boat is a motor sailer with internal lead ballast and external lead laid into the keel. I have a sail plan smaller in proportion than the sail area specified in the Couta Boat Club's design rules found on their web page:
http://www.coutaboat.com.au/wp-content/uploads/2013/10/COUTA_SAIL_AREA_CALCS.pdf

http://www.coutaboat.com.au/wp-content/uploads/2013/10/Couta_Sail_plan09.pdf

https://i.postimg.cc/MTtNcrVF/Couta_Sail_plan09.jpg

Other details:
http://www.coutaboat.com.au/official-class-rules-2011-2015/#tab-id-17

I was advised that my boat Warana would be a bit over canvassed for a bass strait blow so have gone with the sail plan for the 26 ft boat.

skaraborgcraft
10-02-2018, 01:50 AM
This is the only photo i have of my old ferro gaffer...

23866

That was a telephone pole found laying around, keel stepped, with only a forestay and a single shroud each side. The sail was a large bermudan sail cut down, with a Hurley 22 boom used as a gaff. I could not have built this rig any cheaper than i did at the time, and it got us from the UK, across Biscay and into the Med via North Spain and Portugal. I do like the idea of tabernacle masts, but this pole was so heavy, there would have been substantial amount of extra work and weight to have done that. As Bruce says, there is a saftey factor to the mast being keel stepped.

skaraborgcraft
10-02-2018, 01:58 AM
Sadly, not much info on touchstones rig. Brief write up about Mike here:

https://www.yachtingworld.com/cruising/mike-peytons-guide-to-becoming-a-bargain-basement-yachtsman-an-extract-from-his-book-quality-time-108748

FF
10-02-2018, 02:57 AM
You will find the information in Skene's Elements of yacht design. I built a ferro gaffer with the mast in a tabernacle in the 80 's. Saw her in a marina last week, still looking fine. Enjoy your boat.

Corella
10-02-2018, 03:07 AM
The techniques for calculating mast and other spar sections are given in "Skene's Elements of Yacht Design" by Kinney (the classic text on yacht design, get a copy, generally available used on Amazon - cheap) and more recently in "Principles of Yacht Design" by Larsson,etc.
A bit of maths but not too hard. Kinney has lots of graphs to do most of the calcs for you. Or you could employ a NA to do the same thing.
If you're planning on going offshore, or Bass Straight get it right!!

Hwyl
10-02-2018, 03:56 AM
Sadly, not much info on touchstones rig. Brief write up about Mike here:

https://www.yachtingworld.com/cruising/mike-peytons-guide-to-becoming-a-bargain-basement-yachtsman-an-extract-from-his-book-quality-time-108748

Apparently it was embarrassingly slow. An experiment that didn’t work.

skaraborgcraft
10-02-2018, 04:16 AM
You will find the information in Skene's Elements of yacht design. I built a ferro gaffer with the mast in a tabernacle in the 80 's. Saw her in a marina last week, still looking fine. Enjoy your boat.

They can, but another friend lost his mast over the side due to a single chain plate failure, would not have been so bad, but the tabernacle took about 4sq ft or ferro deck with it, and that was the biggest issue he faced in that particular gale, he had to cut the rig away. A Russian freighter stood by and transferred enough diesel for him to make land in Western France.
My thoughts on tabernacle these days with heavy spars is to take them down to the keel, uses more space than a plain
spar, but at least it can be lowered without a crane. Bolger drew some substantial ones suitable for offshore.

Geftb
10-02-2018, 04:38 AM
Do you intend to make her a gaffer or get a bermudian main?

It's your "essentially follow the rig that's there" part has me wondering.The gaff main on that mast is....just wrong.
She appears to be a fat and full vessel,one that could carry a proper gaff rig.
Plenty fine lookin.
bruce

Sorry Bruce I missed part of this comment in my rush out the door this morning. What I mean by "using what's there" is simply, spar placement, rake and lengths. Except the gaff, that needs to be lengthened.

Geftb
10-02-2018, 04:40 AM
That's a great looking boat you have there Steve. Portland is my home town but living on the Mornington Peninsula now. I have a very similar hull 30 ft long and am happy to talk couta boat details.
The mast of a couta boat will be as tall above deck as the boat is long. I'm working on my 30 ft mast at the moment. It is deck stepped in a tabernacle. When i find pics i will post them although there are a few in my thread about Warana, but Many pics went AWOL because of photobucket:

Thanks Hallam, chat soon

Geftb
10-02-2018, 04:47 AM
Thanks for the link and your story Skaraborcraft.

Cheers FF!

Thank you Corella. I will see how I go here over the next few days. Next option is to contact the Wooden Boat shop in Sorento. As you say, it needs to be right.

Geftb
10-02-2018, 05:01 AM
OK, so please excuse the butchering of this boats fine lines in the below sketch. But I'm thinking if I follow these placements, rake etc and make the mast 190mm/7,1/2 inch and step it to the keel, I'm going to be a long way ahead of where I am now. I need new sails, rigging, cleats, blocks, reefing anyway. May as well do it right.

23868 All measured from the boat on the weekend. She is actually closer to 36 ft.
I will need a new sail plan of coarse.

wizbang 13
10-02-2018, 10:59 AM
Hoo boy thats a chunky drawing.
If I may....
Lower the mainsl tack and raise the mainsl clew as much as you can. Considering if there might be a dingy up the someday, I hope not.
Draw a line from the mainsl clew to the throat...the gaff should be 90 degrees out from this line.
When planning reef points, make the clew of each reef a bit higher than the reef tack...reefs have a habit of getting tied in poorly and the boom drops lower and lower.
Backstays are not for holding a mast up ,they are for making the headstay tight.
My boat , and others, has 7 feet at the top with no shrouds or stays.The only thing up there is a beefy cheek block for the topsl halyrd.( and some light/antennae crap).I used to have a seized block for the flying jib (third lightweight jib) halyard.
I think you wanna figure out square footage of the rig. A gaffer does NOT want a big jib or genoa. The lack of sophisticated rigging cannot tolerate the compression. Many beginners on gaffers try to carry big jibs..they are a bad idea on gaffers. More sail area in the main and topsl make less strain on the rig and crew. If the boat has too much helm, make a longer bowsprit.
bruce
https://farm2.staticflickr.com/1948/43245307280_0f612031b3_z_d.jpg
I moved the throat up a bit and put the mainstay a bit above that.
The luff of the top should be the same as the luff of the main(imo)

wizbang 13
10-02-2018, 11:36 AM
When sitting still, the top of the mast should "tweak" forward a bit at the top. Grinding in the mainsheet upwind will pull it back, inducing some tightness into the outer stay.
If the diameter of the mast is beefy enough, you do not need running backs.
Topping lifts and lazy jacks are an important part of a cruising gaffer. They do much more than hold the boom up.Setting them up correctly is often done wrong.
Now, all this crap Im giving you here is just stuff Ive learned over time in the world. NONE of it is bona fide designer NA stuff, so keep that in mind, for better or for worse.
We have two threads now, Australians converting macaroni rigs to gaff, you and Wee Barkie.

Geftb
10-02-2018, 03:14 PM
Well that looks about 8 million times better. Thanks mate, you have given me a lot to work with. I will have to set up my old drawing board and get to it. I should be busting out the table saw this weekend.

"Now, all this crap Im giving you here is just stuff Ive learned over time in the world. NONE of it is bona fide designer NA stuff, so keep that in mind, for better or for worse."

I am very aware of that and take full responsibility for any and all of my actions! All good mon.

wizbang 13
10-02-2018, 03:43 PM
more thoughts,
The spar is untapered to the lower shrouds, then evenly tapered to the truck.
Two lower shrouds,one slightly forward of the partner ,the other slightly aft.
One upper shroud, furthest aft.

Phil Y
10-02-2018, 04:05 PM
My dads 23 footer. Not a couta boat, but based on a traditional south Australian fishing boat. On such a small boat, no real place or need for a topsail, but peak the gaff up a bit higher, almost a Gunter rig.
23894

Geftb
10-04-2018, 06:10 AM
Jeez, You can see the similarities in the hull shapes! The South Australians must have copied the Victorians :d

OK... I have set up my old drawing board and started busting out some lines and very well may have stuffed up my workings out of sail area... But its a start and everything will be checked and double checked as we go along.

23958

Can you see that? I could before I loaded it. Might have to blow it up?

Geftb
10-04-2018, 06:15 AM
Main 451 sq ft (see adjustment below)
Topsl 63 sq ft
staysl 194 sq ft
Jib. 345 sq ft

Total. 1053 sq ft (see adjustment below)

Mast Height. 38 ft from deck level
Mast width 7.5 inch to the lower shrouds
5.5 inch at the truck

edit...

Sitting here looking at it I saw 2 clear triangles within the Gaff main. Re-calculating I came to 414 sq ft which I believe to be the correct calculation. (Learning this as I go)

Main 414 sq ft
Topsl 63 sq ft
staysl 194 sq ft
Jib. 345 sq ft

Total 1016 sq ft

wizbang 13
10-04-2018, 08:20 AM
Can you sketch those lines in a bit darker? Can't see em.

Geftb
10-04-2018, 02:49 PM
23984

That should be better.
Checked my maths again, and I forgot to half the base on the head sails so new areas below.

Main 414 sq ft
Topsl 63 sq ft
Headsl 97 sq ft
Jib 173 sq ft

Total 747 sq ft

Cheers Steve

wizbang 13
10-04-2018, 04:56 PM
The inner stay cannot go below gaff throat. Either the gaff needs to come down (longer topsl luff) or the stay needs to go up. (I'd go with the longer top hoist )
It's not at all uncommon to carry the topsl with a reef in the main,fyi
Another thing to consider, I like to keep the clew of the jib below where I cannot reach it.Dunno how high you have drawn that clew,no biggie.
You plan on the main sheet staying all the way back? Consider this.... Gaff clearing the topping lifts when hoisting and dropping. .... It is best to have the lifts reach the boom before the end of the gaff so you do not need to "fish" the gaff through . A real pita in anything but good conditions. With a 13 foot gaff and 21 foot boom, 8 feet of boom beyond the gaff when the gaff is down. Lets say 9 feet of boom extended beyond the toppin lifts . Best engineering is to have the lifts and sheet go to the same place on the boom, or close. Thus...If you lower the throat and lenghten the gaff, It be better support for the boom . Again, no biggie.But try drawing her with the gaff down and the topping lifts and mainsheet.
My 34 Venus has a 14 'gaff and boom. 250' main and 100 'top for comparison.

Geftb
10-04-2018, 06:16 PM
Thanks Bruce, that's all clear Y>
i will get onto it this afternoon

Geftb
10-05-2018, 05:28 AM
Changed things up a bit.
24015

I have lifted the boom another couple of degrees and shortened it 6"
Lengthened Gaff to the same length as the boom.
As a result the Topsl is now a shade over 100 sq ft.
Dropped the main throat and lifted the Staysl.
Shortened the jib somewhat.
Added topping lift and lazy jacks.

skaraborgcraft
10-05-2018, 06:21 AM
How much lead % are you going to give the sails centre of effort over the hulls lateral resistance?

Geftb
10-05-2018, 06:52 AM
Well, I've learned a lot these last few days so why not enter into (for me) uncharted waters. In other words, I don't know :ycool:
I did happen to find this in a box that his wife gave me. It appears at some stage it was going to be set up as bermudian and then his changed his mind to gaff???
24017

Not sure if you can see it clearly. It may contain enough information for me to figure it out.
There is a note at the bottom right hand corner of the page that says, "shift mast forward 3" with same rake as shown. Provide slope aft to c'plate".
I was simply going to follow his mast placement. seeing as the sail plan has changed Im guessing all that goes out the window? At least I have that drawing so it shouldn't be to hard to work out?
Thank you for the question!

wizbang 13
10-05-2018, 07:48 AM
I am not suggesting you make the gaff the sames as the boomm for a sloop or cutter, only that mone are the same for a ketch.
I am completely ignorant of what all these letters mean. I know what they stand for but I do not know what they MEAN.

Geftb
10-05-2018, 08:08 AM
Same, I'm up for learning though. I think you made a comment earlier Bruce that "If the boat has too much helm, make a longer bowsprit." What if its lee helm and I need a bigger main? that will get expensive.

Junkyard Dog
10-05-2018, 08:20 AM
With all this talk of building a keel step, I haven't seen anything about partners at the deck. Not knowing anything about your build, I can't offer any suggestions except to consider constructing some beefy mast partners to carry some of that side loading.

Geftb
10-05-2018, 03:45 PM
Hi Junkyard, I'm fine with figuring all the structural component aspect out myself.
It's the technical stuff I need some help with. But I'm getting there.

FF
10-06-2018, 09:39 AM
2407824079 This is the first boat I built. Ferro hull, plywood deck, steel tabernacle because I often sailed her in inland water and I wanted to be independent of cranes. On a bigger gaffer I would have had a preference for a keel-stepped mast, but here even big boats have tabernacles.

Geftb
10-07-2018, 12:17 AM
Beautiful little ship FF! I think for inland waterways a tabernacle is a great idea. I may want to sail to New Zealand one day though. Or the Pacific Islands. I need a keel step.
Latest sail plan. I have lengthened the boom by 2 ft, shortened the Luff and matched the Gaff to the Luff dimension.
I have been researching how to find CLR. I have come to the conclusion that without a set of plans for the boat... Well, it's beyond my maths.
I going with the theory that Theo has worked mast placement out at the time of building and will go with a sail plan that is common with this type of boat.
24107
Comments welcome as its all still static.

Corella
10-07-2018, 02:05 AM
Bring the boat alongside a dock on a calm day. Center rudder, stand on dock with a boathook and push the boat way from you (or pull it) as you move alongside the boat. When you find the spot that it moves away from (or towards ) you squarely you've found the line the CLR runs through - at rest, zero heel angle.
Works on dinghies, maybe a bit tougher on a large boat(pulling towards you may work better.)

FF
10-12-2018, 01:55 PM
Geftb, imo the staysails should overlap the mast slightly for most efficiency. And I like a jib on a long jibboom but now I would prefer to have her on a roller like they do for a code zero. If you do that, anti torsion line and endless roller, choose a modern one instead of the nostalgic brass one I. You will not regret it.

FF
10-12-2018, 01:57 PM
Corella, I never heard of this, seems so simple, very ingenious.

Geftb
10-12-2018, 05:08 PM
Ahhh, I finally get it after reading it 50 times. I was picturing pushing pulling from the stern. Thanks, I will have a play with that when she goes back in the water. I won't finalise the sail plan until then. Mast can still go in though. Cheers!!
Thanks FF, I will look into it.
I've been very busy on the work front these last couple of weeks. Onto mast building in a fortnight or so.

Corella
10-13-2018, 01:27 AM
Can't take credit for it, read it somewhere.........
(Can't find my source now, of course!)

Geftb
06-30-2019, 04:41 AM
What do you think Bruce? Its basically your rig copied here with an extra six inches on each sail to help with mast placement.
I've been reading the mizzen thread and dont like the idea of having a +400'2 sail in 40 knots.
Ive been busy painting and preparing the boat and stuck at work the last few months. Would like to be installing masts in around spring time.

40329
40331

auscruisertom
06-30-2019, 05:51 AM
Paint job is looking great.
I like the split rig ,that 21 foot boom with overhanging main sail on your original plan would concern me even with lazy jacks.

Geftb
06-30-2019, 06:15 AM
Thanks Tom,
Long story short, my boat yard neighbor loaned me his compressor (and gave a crash coarse) and I purchased myself a cheap spay gun form auto barn.
The main benefit of spray i believe is wet on wet application. 3 coats of primer in an afternoon. sand it 2 days later then 2 top coats in a couple of hours.
This compared to drying times and sanding between coats saved me many days work.
I'm liking the split rig also!

Cheers Steve

skuthorp
06-30-2019, 06:51 AM
Interesting discussion, I have two vintage model Couta Boat hulls, one planked, the other carved from a block of red cedar.
I like to keep old pond yachts 'as found' mostly, but I may make an exception based on this thread.

Phil Y
06-30-2019, 04:47 PM
How did I lose track of this thread? I'm very much in favour of a high peaked gaff and no topsail. You are going to spend several boat bucks on rigging and sails. No disrespect but I'd spend some money on a naval architect or whatever first. Think of it as a foundation.

Sent from my CPH1851 using Tapatalk

Geftb
06-30-2019, 05:19 PM
Not a bad idea Phil! It a can open a can of worms though. If I had a plan for the hull it would be a simple phone call. What's involved in taking the lines from an existing hull. I think I've seen Jay doing it.
(edit: I am still interested in Bruce's thousands of miles experience with these rigs though. Bruce, you out there?)

wizbang 13
07-01-2019, 06:41 AM
Oh hey Steve,
Thanks for the PM, I was asleep at the wheel.
Ya, I'm getting a tingle now.
I am so god damn fussy about boats I will go to sea on, but a well found gaff ketch ...well.
The topsl and or the mizzen are the two easiest sails to strike and set, barring modern rollergear, so I'd never go to the high peaked main with no top for short handed cruising.
Plus, There is sailmakers geometry.... draw a line from the clew to the throat...90 degrees out from that is the gaff angle, thus..longer boom equals higher gaff. Shorter boom equals bigger topsl. Now, maybe this"rule" need not be followed with modern sailcloth. I think it evolved from cotton/canvas weave...not sure.

I see my early drawings went away...that is the FLICKER bend over,sorry, but you have the idea down now.
Of course, If you can have a pro review...can't be a bad thing.
b

Geftb
07-01-2019, 03:57 PM
Thanks for stopping by Bruce. What can you tell me about mast placement? Particularly the mizzen.
no offence to pros... but it was a pro who suggested I have that 21ft boom.
Theres always the " if it looks right it is method".

wizbang 13
07-01-2019, 10:18 PM
Eh, well, there may be a perfect place for it, but something may be in the way at this point. Cabin,tiller, shroud placement ... hatch, engine/shaft.
yer boat will sail faster and point higher most of the time with a sporty rig.... duh.
is that what you want or need ?

gypsie
07-01-2019, 10:51 PM
To my eye, the mizzen is cluttering the layout, and, it's crying out for a topmast :d - a non-strikeable one. Might save the tapering of the birdsmouth to get a thinner (lower windage) spar up high.
With the foot of the jib shy of the mast, I'd be seriously considering a self tending one.

She doesn't seem to have back stays?

Nice paint job!

Geftb
07-01-2019, 11:17 PM
I want a rig that gets me there every time. Im not fussed about about sporty.
At this stage I will be going engineless with views of a electric motor when funds allow.
Being quite small the electric motor will fit no problem.
So, mast placement first, engine second.
do you know the overhang of your mizzen boom from the stern?
My boat is a couple of foot longer than yours so I put 6" on each sail and I think it looks pretty close.
Although, it does increase the sail area somewhat

Geftb
07-02-2019, 12:49 AM
Hey Gypsy. I like the idea of the self tending staysail. The rest is a bit wild though. |;)
Im pushing 50 now and knock on wood can still sail her Singlehanded, if need be, into my 70s. She has a shallow draft of 4ft also, (with a 4ft dagger board) so a low aspect rig should work better all round.
Its just a sail plan at this stage, to keep it clear.
Im sold on the gaff ketch. Just want to get the balance right.