Classic Sailing Dinghy Question

[kiwibyron]

Hi all,

I recently bought a boat (my first mistake i know...). It's a small dinghy, 2.7m long and it came with the sail, boom etc. but no mast. There are no markings or anything giving any indication of the make/model/design but its a fibreglass hull with timber boom.

My problem is the boom to mast connection, I can't figure out how this works. Has anyone ever seen something like this before and can shed any light on what I've got here?

 

[jviss]

Those look like the jaws of a gaff.

 

[31seahorse]

Hello & Welcome kiwibyron,
I agree that the boom connection looks like jaws for a gaff rig. It would slide up and down a bit as the sail is raised and move a bit from side to side as the mainsail is eased out or pulled inward. The mast would be generally round at least where the boom contacts the mast. Perhaps even some metal or leather wrapped around the mast where the boom fork contacts the mast. (1) A picture of the hull might help someone identify the boat. (2) A picture of the sail would define what type of sail (its shape) you have. Are there wooden hoops on the luff of the sail? They would be above that fork shaped end of the boom. (3) Looking at the registration paperwork, if there is any, will list the manufacturer of the boat. (4) Previous owner(s) might know if you have not already asked them. (5) Look under, inside, every part of the boat for identification if there is none on the starboard side of the transom. (6) What year is the boat according to any information you have? (7) Is there an insignia on the sail?

 

[shemandr]

I agree. That is the connection to the mast. This works because the boom is compressed into the mast by the forces on the sail. On my Marblehead Skiff I closed the open jaw with a line (Knotted for some reason). I also had a downhaul line on it (Or your case the boom).

 

[Will Gilmore]

Welcome to SBO kiwibyron, it is good to welcome you to our awesome online crew.
What you have there is a homemade rig. I don't know about the boat, but that crotch is home welded and, I'm afraid, doesn't look like marine grade steel. No matter, it should perform well enough when rigged with some form of capture line looped loosely through the tack around the mast.
We all would like to see pictures of the whole boat and rigging.

-Will (Dragonfly)

 

[kiwibyron]

Hi All, thanks for the replies!

I agree it looks like a gaff. I had envisaged something like you mention 31seahorse, some sort of metal sleeve around the mast that allows the boom to move up and down a bit with the boom connection loosely tied around the mast.

I've attached photos of the hull, sail, and the seat of the mast. Note the square seat, so i guess the mast (which i assume was also timber) had a square base and was rounded for the rest, likely starting about where the boom connection is.

The sail is slightly curved along it's height (~3.2m), the breadth at the bottom is ~2m. No wooden luffs. I don't have any rigging at this point. I do have the tiller and centreboard though. As you'll see in the photos the transom was completely rotten so I've removed it.

I have no paperwork at all but I've been in contact with the guy i bought it from, it was his sons boat. His son will be back in the country in a month or so and might be able to shed some more information and maybe even find the mast from wherever he put it.

I would be massively thankful if someone could identify the type of hull, or even just give me an idea as i'm not expecting it to be anything particularly special or unique. As you can see in the photos I've removed all of the timber trim as it needs to be replaced. I've got some Kauri boards to cut up to replace it with (shown underneath the mast seat).

 

[Will Gilmore]

That is a pretty little boat.

-Will (Dragonfly)

 

[31seahorse]

The lap strake look of the hull is a nice feature in my opinion. Of course you are saving the pieces of wood you removed so you can use them as patterns. The boat has "redundant" means of propulsion: sail, row, or power (with a small outboard). The mast will be a challenge.....find out what wood was used for the boom and see whether the same type is available for your mast. Perhaps epoxy to unite several overlapped pieces will be necessary. Start with a long, square length and shape with a draw knife. Great DIY project! I'll research sailing dinghies.

 

[kiwibyron]

Thanks guys, the lapstrake is what caught my attention first too. I would be grateful if anyone can pick the hull design.

I am keeping the old pieces, i managed to get the inside and outside trims off in one piece on one side, the other side disintegrated quite a bit though, it's so rotten. The corner bits were pretty rotten too but managed to get one off OK. The seat looks like it's been DIY replaced previously as it was made with tongue and groove timber! I couldn't even lean on it let alone sit on it.

For the mast I'm hoping that the previous owner will come through, but if not I'll have to get creative i think as i'm not seeing many timber masts for sale.

Google searching based on a bit of terminology you guys have given me produced gaff jaw that looks similar to the boom-mast connection i seem to have going on here, see below. The little rubber/poly hose would allow a bit more grip to keep the boom attached.

 

[Will Gilmore]

What are some of the basic dimensions? How long is the boat, her width? How long is the boom and what is the luff length.

As far as making a mast, a good piece of clear spruce should work. Dimension lumber is made from spruce and fir. P.t. lumber includes yellow pine. All of those have been used extensively for spar material. It may take a lot of picking through. You might be able to just order a dowel of the right length or scarf one together with a 7:1 scarf joint.

-Will (Dragonfly)

 

[shemandr]

It's a blessing the seat is out. Now you make your own. On the pram and skiff I built I put "H" on it's side shaped seat with the centerboard in the middle. I based this on the fact that you want to sail a small boat with your weight in the middle fore and aft wise. The cross of the H allows you to slide across to trim the boat side to side and then once reaching the bunk on one side or the other you can adjust forward or aft. Or have a passenger.
Masts can be difficult to build. The Off Center Harbor web site has a video on how to make a hollow Mast. It's pretty complicated but might be fun. I had a local boatbuilder build mine. Or you could look for a sunfish or other small boat aluminum mast.

 

[BudGates]

Google searching based on a bit of terminology you guys have given me produced gaff jaw that looks similar to the boom-mast connection i seem to have going on here, see below. The little rubber/poly hose would allow a bit more grip to keep the boom attached.

The picture with the sail and boom makes it clear that what you have is a cat rig with an old-fassioned gooseneck rather than a gaff rig but the concept is the same. The forks simply hook around the mast to hold that end of the boom left to right. With the sail pulling it up and the down-haul pulling it down it stays in place vertically. A short line to keep it from pulling away can be helpful but is not essential since the out-haul holds it against the mast.

 

[jviss]

cat rig with an old-fassioned gooseneck rather than a gaff rig

Most of the catboats around my waters are gaff rigged, the most popular being the Beetlecat.

 

[TomY]

Hi All, thanks for the replies!

I agree it looks like a gaff. I had envisaged something like you mention 31seahorse, some sort of metal sleeve around the mast that allows the boom to move up and down a bit with the boom connection loosely tied around the mast.

I've attached photos of the hull, sail, and the seat of the mast. Note the square seat, so i guess the mast (which i assume was also timber) had a square base and was rounded for the rest, likely starting about where the boom connection is.

The sail is slightly curved along it's height (~3.2m), the breadth at the bottom is ~2m. No wooden luffs. I don't have any rigging at this point. I do have the tiller and centreboard though. As you'll see in the photos the transom was completely rotten so I've removed it.

I have no paperwork at all but I've been in contact with the guy i bought it from, it was his sons boat. His son will be back in the country in a month or so and might be able to shed some more information and maybe even find the mast from wherever he put it.

I would be massively thankful if someone could identify the type of hull, or even just give me an idea as i'm not expecting it to be anything particularly special or unique. As you can see in the photos I've removed all of the timber trim as it needs to be replaced. I've got some Kauri boards to cut up to replace it with (shown underneath the mast seat).

I can't place the boat but the photos give some clues as to the rig. It looks like it has a wooden spar, the likely evidence being the square hole in the step. I'd guess the rig was stayed as there is no step forward in the hull. Could be simply 3 stays?

If that's the case (stayed), the spar wouldn't need to be too stout and you could build it from clear-ish spruce dimension lumber. Perhaps 2 2X4's sandwiched in epoxy, re-saw to ? , taper, round (or not) and cut the end square to fit the square hole.

I think you show that step (with the square hole) goes over a seat. That needs to be strong enough for the downward force but doesn't need to be as strong as an unstayed mast going through the seat and into a base step which has considerable twisting force.

You're luckier to have the rudder and centerboard, they would be more work to duplicate. Looks like a good dinghy sailer!

 

[BudGates]

Most of the catboats around my waters are gaff rigged, the most popular being the Beetlecat.

That may be so (my Montgomery originally had a gaff rig) but the sail in the photo isn't.

 

[DrJudyB]

There are no grommets or slides on the luff of the mainsail . It appears from the picture that there is a bolt rope in the luff which requires a groove in the mast.

The luff of the mainsail shouldn’t be concave ( hollow) like that. It should have a slight positive curve. I suspect the bolt rope along the luff has shrunken. I couldn’t tell for sure from the photo when I zoomed in because the resolution wasn’t high enough. Nevertheless, based on years of experience selling sails, everything about the sail suggests the bolt rope has shrunken. The major visual cue is that its curved the wrong way at the luff, and there are a lot of wrinkles along the luff that you can’t effectively stretch out.

That will make the sail very deep. (And it looks *very* deep in the picture to my eye). The luff is now shorter than designed to be, and The boom will drop at the aft end.

You can detach the bolt rope where it’s seized at the top and bottom to ease the wrinkles out. Then add a few inches of new rope at the bottom. Google “ release a shrunken bolt rope mainsail” for detailed instructions. That sail cloth is very old, and it might not last much longer.

It may be that the boom is home made and not part of the original rig. The sail may not be part of the original design either. I would suggest you think outside the box. dont limit yourself by building a mast to match a sail that is close to the end of its life and the existing boom.

So you might want to look around for a different rig and sail. Or build a new rig and sail.. check out Duckworks online for a source of small boat plans and supplies.
I wouldn’t be surprised if restoring this boat costs you a fair amount of money. Putting all the pieces together will probably cost more than the price of a small dinghy that has all the bits and pieces in one place.

Judy Blumhorst
Retired sailmaker

 

[kiwibyron]

What are some of the basic dimensions? How long is the boat, her width? How long is the boom and what is the luff length.

The hull is 2700mm long and she’s 980mm wide at the stern widening to about 1200mm.

The boom is 2200mm long, luff length 3200mm.

Could be simply 3 stays?

Yes, based on the hardware on the hull I think it’s it’s 3 stays.

It appears from the picture that there is a bolt rope in the luff which requires a groove in the mast.

Yes there is a bolt rope along the foot and luff. I think you’re right that the rope has shrunk which is annoying. I know a sailmaker so will have a chat to him about fixing it.

Any ideas on the rigging for this setup?

 

[BudGates]

Any ideas on the rigging for this setup?

I'd start here Rigging Small Sailboats - Chapter 5

My choice would be fig 5-4 but it's all up to you.

 

[Will Gilmore]

The original Mariner 19 sheeting is called a Crosby rig. It looks like figure 5-5. I'm partial to figure 5-8 with the sheet block pinned in the middle of the harness. The Windmill has a modified version of this that is adjustable from side to side. And my pram, when I was a kid, used figure 5-4, like BudGates suggested. It worked very well and was easy to setup.

-Will (Dragonfly)