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scoober
01-24-2018, 03:58 AM
I'm in the process of buying a cornish topsail for my gaff cutter, and need to make both a luff yard and a jackyard for it (hopefully from the douglas fir offcuts from my new bowsprit). The sailmaker has given me the required lengths, but wasn't sure on the required diameter. The sail is 60sqft with a 18ft luff (requiring a 19ft pole). If anyone has a similarly-sized topsail, would you mind sharing the spar dimensions so I have a couple of data points to work from?


For a bonus question, if anyone has any good ideas for mounting the timminoggy, I am all ears. My gaff saddle arrangment (similar to https://www.classicmarine.co.uk/images/gaffs1.gif) makes it undesirable to drill into the side of the gaff at the forward end, so I'm interested to hear what others have done.

Thad
01-24-2018, 05:45 AM
I think my yard is about 2" diameter, jackyard 1.5", both taper a little toward the ends, especially toward the tack end.

wizbang 13
01-24-2018, 05:46 AM
How far beyond the mast will the head be and how far beyond the gaff will the clew be?
I recon a start of 2 and a half inch where the halyard and sheet tie to the spar, tapered at both ends to about an inch and a half.
This may be a bit heavy, but leave them un painted(or varnished), that it is easier to hand plane more off if needed.
Sounds like a top for a sporty small boat.

Peerie Maa
01-24-2018, 06:48 AM
Skene's does not specify topsail yards, but recommends 0.02 times length for a gaff and 0.021l for a jib club Which is closer to Bruce's recommendation.
By timminoggy do you mean the line that pulls the heel of the topsail yard into the mast? If so just shackle a small turning block to the gaff saddle, may be to where the throat is attached.

Ian McColgin
01-24-2018, 07:39 AM
Scoober, so far as I recall you are the only person besides myself to use the term "timminoggy" on this Forum, though I'm sure you and I are not alone in knowing the word.

As used around here, a timminoggy is any line rigged to prevent other lines from fouling. My most common use is on the foredeck of boats that have jib sheets prone to foul on a mooring cleat of windlass. For such boats I rig a timminoggy from somewhere on the mast (typically about at the gooseneck) down to something on the foredeck or even to the stem. Keeps the jib sheets up.

So, I share Nick's uncertainty as to what you mean. The only time I rigged a boat with luff yard and jack yard, both were a little shorter than the luff and foot and the tack cringle was attached to a long line to a cleat on the mast. That gave me control of luff and foot tension.

On that boat we never came up with a good way to rig a double ended tack downhaul with the lazy part draped over the peak halyard to allow pulling the lower part of the topsail over to leeward of the peak halyard. It did not seem to matter tack to tack whether the topsail lay against the peak or to leeward of it. I think about the only way to switch sides would be on a large boat where a hand (in the International Fisherman's Race a young Sterling Hayden had this job) swarmed aloft to muscle the sail over.

On that boat what I called the peak halyard simply went through a hole at the end of the gaff. When not in use both parts came down on either side and were secured to the boom a bit abaft the gooseneck. The throat halyard was similarly one part on each side. That way no matter what tack we were on it was easy to set the topsail in the main's lee.

There are about as many ways to actually rig a gaff topsail as there are gaff topsails so feel free to experiment, steal and mix ideas from other boats, and if you end up rigging a line that no one else seems to use, make up a name with plenty of sea dog swagger. Just remember that "scrudgeon" is taken and is not a line anyway.

Peerie Maa
01-24-2018, 07:53 AM
The issue here is that a Cornish yard topsail was set (on Flamouth Quay Punts) over a very short pole headed mast. So the topsail yard stood like a reeving topmast and needed something to make it stand upright. I think that timminoggy may be the local term for the heel rope that carried out this function.

Rich Jones
01-24-2018, 08:37 AM
The day has been worthwhile waking up to. I have learned a new word: timminoggy!!

scoober
01-24-2018, 09:42 AM
How far beyond the mast will the head be and how far beyond the gaff will the clew be?
I recon a start of 2 and a half inch where the halyard and sheet tie to the spar, tapered at both ends to about an inch and a half.
This may be a bit heavy, but leave them un painted(or varnished), that it is easier to hand plane more off if needed.
Sounds like a top for a sporty small boat.

Around half the length of the luff yard will be above the mast cap - so approx 9ft. By my reckoning, the clew of the topsail won't extend much beyond the end of the gaff, if at all.

The boat is a Heard 28 Falmouth Working Boat (sorry the hull isn't actually wood - but everything else is).

With regard to tapering the luff yard, would there be any issues with the luff of the sail being straight and the yard tapered, or would it sort itself out?

scoober
01-24-2018, 09:49 AM
Thanks Ian, apologies if I was unclear. The timminoggy is a fairlead for the topsail downhaul that is fixed to the forward end of the gaff. As Peerie Ma said, the topsail yard will extend about half its length above the mast cap, so the bottom part of the yard needs to be pinned in to keep it under control. Because it also functions as a kind of topmast I am vacilating a bit between making it quite chunky to keep the luff of the topsail taught, and being afraid of making it too big to manhandle.

scoober
01-24-2018, 09:57 AM
Skene's does not specify topsail yards, but recommends 0.02 times length for a gaff and 0.021l for a jib club Which is closer to Bruce's recommendation.
By timminoggy do you mean the line that pulls the heel of the topsail yard into the mast? If so just shackle a small turning block to the gaff saddle, may be to where the throat is attached.

Thanks. When you say .02 times length, is that .02 times the length of the yard?

It strikes me that a nice solution might be to have a double block with the downhaul running through one and the topsail sheet through the other. The pull on the topsail sheet would also help pull the block into the gaff to stop it moving around any.

My gaff jaws hinge on a galvanised pin, and I am now wondering about replacing this with a eye bolt and shackling the block to this. Does that seem like a reasonable idea?

Peerie Maa
01-24-2018, 10:05 AM
Around half the length of the luff yard will be above the mast cap - so approx 9ft. By my reckoning, the clew of the topsail won't extend much beyond the end of the gaff, if at all.

The boat is a Heard 28 Falmouth Working Boat (sorry the hull isn't actually wood - but everything else is).

With regard to tapering the luff yard, would there be any issues with the luff of the sail being straight and the yard tapered, or would it sort itself out?

The taper is not that great over the length of the yard, it should be OK.
If the topsail clew is not going past the gaff end, why do you want a jackyard? Or is it just a short club that you need?

https://upload.wikimedia.org/wikipedia/commons/6/65/StMelorus.jpg

Ian McColgin
01-24-2018, 10:11 AM
Timminoggy as a fairlead, not a line. Well, why not. It's one of those words like "thingamajig" or "framis" that might be most anything. And the line I call a timminoggy is a sort of non-specific fairlead.

The purpose is to hold the spar against the mast, which it probably does a bit more effectivly than just hauling down hard to a cleat. The disadvantage is that you can only set the topsail on one side.

I'd be inclined to run the tack rope or heel rope straight down as an experiment. With the halyard at about the half way point up the yard, the stresses pulling the tack away from the mast might be about equalized out and just not a problem.

Fun with boats. G'luck

Peerie Maa
01-24-2018, 10:30 AM
I'd be inclined to run the tack rope or heel rope straight down as an experiment. With the halyard at about the half way point up the yard, the stresses pulling the tack away from the mast might be about equalized out and just not a problem.

Fun with boats. G'luck

That wont work, the leverage as the top of the sail blows off will break something.
Lancashire nobbys had a similar problem, but set the topsail like a standing lug.
10058

wizbang 13
01-24-2018, 11:37 AM
As long as you are having a stick, make it as long as you can . Will it stow in the lazy jacks, alongside the boom?
I never heard that word either. The luff of my tops (two different boats with topsls) behave okay, but I can always swing the tackline into the front of my gaff jaws. It forces the top tack forward, but adds a chafe element.

scoober
01-24-2018, 12:12 PM
As long as you are having a stick, make it as long as you can . Will it stow in the lazy jacks, alongside the boom?
I never heard that word either. The luff of my tops (two different boats with topsls) behave okay, but I can always swing the tackline into the front of my gaff jaws. It forces the top tack forward, but adds a chafe element.

I dont have lazyjacks, but I'm hoping to rig something to store it along the boom, hopefully without interfering with the reefing comb/pennants. I'm hoping it will conceal the rather amusing droop in my boom.

scoober
01-24-2018, 12:17 PM
If the topsail clew is not going past the gaff end, why do you want a jackyard? Or is it just a short club that you need?


It's relatively short at 6ft, amd I suspect it is more for the set of the sail (or possibly just tradition). Incidentally, that picture appears to be the boat that the mould for the Heards was taken from. Mine has the cruising version of the rig, without the mini second bowsprit.

Peerie Maa
01-24-2018, 01:49 PM
It's relatively short at 6ft, amd I suspect it is more for the set of the sail (or possibly just tradition). Incidentally, that picture appears to be the boat that the mould for the Heards was taken from. Mine has the cruising version of the rig, without the mini second bowsprit.

I don't think that it is traditional. It will only be needed if the sheet is attached forward of the topsail's clew.

Pitsligo
01-24-2018, 04:35 PM
This is my 19' sloop, Bucephalus. As you can see, she has a very short masthead, and about 2/3 of the topsail yard stands above the halyard block, a cheek block on the port side of the mast, <2" below the cap (please ignore the tangled red streamer that *should* be flying from her gaff peak):

https://farm9.staticflickr.com/8636/28035254500_55d40cd4f7_b.jpg

To control the heel of her yard, I used to use a separate line rove through a timminoggy screwed to the side of her mast. I later went to a simpler arrangement, using the fall of the halyard rove through a timminoggy and then through a thimble, seized to the heel of the yard. Eventually the timminoggy morphed into this casting, that I call a "heel hook":

https://farm5.staticflickr.com/4666/39170031854_d6f608d596_c.jpg

It does demand that the yard be leathered, to avoid chafe, but it works like a charm.

Alex

scoober
01-24-2018, 05:00 PM
Thanks Alex, that looks like a very tidy arrangement.

Out of interest, what sort of diameter is your luff yard? It looks moderately chunky in the photo in comparison to the mast.

Pitsligo
01-24-2018, 09:24 PM
Out of interest, what sort of diameter is your luff yard?

I'll get you more accurate dimensions when I'm out in the shop tomorrow, but just guessing (wildly) as I sit here in the house, I'll say 1-3/4" max diameter over maybe 12' long. It's two layers of clear sitka spruce, so it doesn't weigh much, and it's about as strong as a spar that size can be. I can fly the kite up to about 18kt, maybe into even higher gusts, but in that sort of wind the yard can get pretty bendy --especially butting into any kind of chop-- and by then the boat is overpowered anyhow, so I generally douse it at ~15kt.

FWIW, it and the jibboom, the smallest spars on the boat, are about the same diameter.


that looks like a very tidy arrangement.

Nothing to do with the hardware or workings of the rig, but the only complaint I have with it is that with the yard so definitely offset to port, the topsail doesn't set as flat on the starboard tack: by simple geometry the twist of the sail as the gaff swings off to leeward means that the distance between the sheet block (at the peak of the gaff) and the yard (rigidly held to port) shortens, thus effectively slacking the topsail sheet. The end result is that the boat doesn't point as high on starboard tack as on port tack. On port tack the geometry reverses, the yard-to-peak distance lengthens, and the topsail is effectively sheeted in; the topsail is also then lying against the peak halyards, which flattens it further. It's hardly a condemnation of the Cornish topsail principle, but it's a frustrating quirk. Without re-cutting the topsail to shorten the luff-to-clew distance, to allow me to trim it flatter on the starboard tack (and necessitating slacking it for the port tack!) I'm not sure there's a cure. Maybe you'll find one --if so, please share the knowledge!

Alex

Pitsligo
01-25-2018, 08:19 PM
Just got in from the shop. My guessing ain't great.

The yard is 1-5/8" max diameter, and it is a total of 10'6" long --but of that, 6" at either end are beyond the bee holes where I seize the topsail's head and nock earrings, so its stressed length (as I see it) --i.e. the length of the laced section of the luff-- is only 9'6" long.

Hope this is useful to you.

Alex