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View Full Version : preferred method of Jib attachment at stem



rkeller
02-16-2011, 07:10 AM
I'm not nearly salty enough, so please forgive my terminology. I'm trying to figure out how best to attach the "tack" of the jib to the top end of the "stem" on a Whitehall we are building. Here is a picture of the stem.
http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/DSC00029.jpg
http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/DSC00030.jpg
http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/DSC00027.jpg

http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/Whitehallsailsample.jpg
Here is a Gardner drawing of the rig.

I've seen boats with nice looking chainplate looking assemblies on the bow to hold the rigging all the way to holes drilled through the stem with a rope lanyard arrangement. I guess my question is: Is there a preferred or best practice method of fixing the tack to the stem?

I was thinking about attaching a bronze eyebolt via a hole drilled into the top of the stem with epoxy.

http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/eyebolt.gif
I know the epoxy is wicked strong but would this type arrangement work or is there something better?

michigangeorge
02-16-2011, 07:25 AM
A bronze strap type chainplate mounted on the face of the stem would be the best. The eyebolt would be an ugly protuberance. Given the small size of the headsail and style of boat the fitting should be small and unobtrusive. The drawing shows what appears to be an eyestrap but it will not work with your stem design. Attaching anything by drilling into endgrain just does not look right to me even though it can be made to work with epoxy.
Looks like you are making good progress on a nice boat :-)

rbgarr
02-16-2011, 07:59 AM
An 'inchworm' bolted through the breasthook would work; out of the way and sturdy enough, leaving the stemhead to be carved into a nice shape. Or a hole driled in the breasthook and a line with a stopper knot threaded up through to the jib tack would do it. Even simpler.

http://cgi.ebay.com/ebaymotors/EYE-STRAP-Bronze-2-1-4-overall-length-4-HOLE-3-4-EYE-/290526081265?pt=Boat_Parts_Accessories_Gear&hash=item43a4b430f1

Harbormaster
02-16-2011, 08:11 AM
Traditionally? Just a hole drilled through the stem head crosswise. Always worked for me.

Robert W. Long
02-16-2011, 08:12 AM
http://boats.duncan.com/caledoniayawl/images/jibfurlt.jpg (http://boats.duncan.com/caledoniayawl/images/jibfurlb.jpg)Here is how it was done on a Caledonia Yawl belonging to Nick Grainger. It is fabricated from stainless steel. On your small boat it could as well be brass or bronze.

Thorne
02-16-2011, 08:16 AM
Good question! Considering the lamination of the stem, I'd be tempted to drill a hole through that and just have a grommet (loop of line) through the hole. Use a SB shackle to attach the jib to the grommet. That way you don't have any hardware permanently mounted on the stem, hardware that may either get damaged or scratch things up when the boat is inverted. The eyebolt is a bad idea!

Do you plan on putting a bow-eye mounted near the waterline on the stem for towing and general painter/bowline use? If not (meaning you won't be towing the boat), then a line / grommet through a hole in the stem will also provide a place to tie or clip a painter to.

It is more 'yare' / traditional to avoid the use of hardware on small boats when a hole and simple piece of line will do - one of the more difficult things for those of us in consumer cultures like ours to accept. I've finally learned to just keep it simple, and not use metal or complex stuff when something simple and cheap works just as well -- or better.

Speaking of yare, I've really enjoyed using hemp and faux hemp line from R&W Rope -- the Hempex is nice to work with and cheaper than most of the bright-colored modern line from Waste Marine. http://www.rwrope.com/traditional-rigging/rope-for-running-rigging.html

You'll want the attachment point to be strong, as with a rig like this where the jib flies free on an unstayed mast, the jib holds up the entire front part of the sailing rig, mainsail, etc -- so it needs to be firmly attached to the boat. I have a somewhat similar rig on my dory skiff.

Not to create confusion or controversy, but do you really want to go for the Gardner rig with such a small jib? As fun as it can be to handle all those extra lines or sheets, many small boat sailors find that a single sail is much easier to handle -- and the balanced lugsail is quite well regarded for many trad boat rigs.

Canoeyawl
02-16-2011, 09:24 AM
As Jim said, a simple strap on the face of the stem is the best.
I have done this using a piece of brass half-oval all down the face with a bit left sticking up at the top having a small drilled hole to accept a little shackle.
I would avoid drilling the hole transversly through the stem as it will be hard to seal out the water and may promote failure of the laminates.
(And I would soon add a cap of some sort for that stem, it will not fair well in the elements.)

rkeller
02-16-2011, 09:25 AM
"but do you really want to go for the Gardner rig with such a small jib?"
No and yes,
No, as much as I like complex things that work harmoniously, like a good Hamilton 992 pocket watch, I know what it's like to have too many things going on at once.
And Yes, there is a small boat regatta in Manteo and Beaufort, NC with a traditional boat class we want to be competitive in. Having a jib would allow us to be competitive and it's was also included in on the center of effort and mast placement calculations...

Thorne
02-16-2011, 12:33 PM
Canoeyawl -

Since from the photo it looks like the entire stem is glassed, I'm guessing that it shouldn't suffer much from the elements if coated with more epoxy, then a good UV-resistant varnish.

And of course a strap would provide both protection and a good attachment point as you suggest.

I hear your objections to the hole, but it could either be drilled oversize, filled with thickened epoxy and re-drilled to size, or have a copper tube inserted in epoxy. I'm guessing that that laminated stem has a fair amount of epoxy already in it, but of course he'd want to be sure it doesn't get opened up to water intrusion and rot.

http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/DSC00029.jpg

rkeller
02-16-2011, 02:43 PM
OK eyebolt idea is tanked.
Chainplate would be a custom thing thus $$$ which I would be willing to do if it was THE right thing to do, I could cut the stem flat or the top flat to accomodate that type arrangement.
More and more I'm liking the idea of a simple hole (3/8" - 1/2") with a bit of copper pipe epoxied in. I could flare the ends of the pipe slightly while the epoxy is still wet then varnish over.
A Hempex lanyard with an eyelet or just a spiced circle of rope for the jib's tack fitting to latch to?

Dave Gray
02-16-2011, 03:00 PM
The Pooduck has a simple hole through the laminated stem. It seems to work fine and you can practice laying up a rope grommet from three stranded line (mine hasn't worked out too well). No pipe, just made sure the hole interior was coated with epoxy and then varnish. If you do that you may need to make the hole slightly larger.

TerryLL
02-16-2011, 04:20 PM
Check out this website. They've got lots of small boat fittings, including simple SS tangs starting at just a couple dollars.

http://www.apsltd.com/images/CATEGORY/medium/79.jpg


http://www.apsltd.com/c-70-boommastbailsstrapstangs.aspx

Wooden Boat Fittings
02-16-2011, 05:52 PM
Chainplate would be a custom thing ...

Not necessarily. A bobstay fitting or a backstay plate is a standard item in many foundries. Either would bolt on the stem to give you a nice anchorage point right where you want it.


http://www.briggsmarine.com.au/images/products/Bobstay-Plate.gif http://www.briggsmarine.com.au/images/products/Back-Stay-Plate.gif

Failing that, you could through-bolt a sash eye to the breasthook, much as Dave suggested with his 'worm'.


http://www.briggsmarine.com.au/images/products/Sash-Eye.gif
Mike

rkeller
02-16-2011, 08:24 PM
Mike I really like the fittings,
What are the dimensions of this and would there be anything like it to be found within 1000 miles of Raleigh, NC?
http://www.briggsmarine.com.au/images/products/Bobstay-Plate.gif

I can see it. : )
http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/stemplate1.jpg

Wooden Boat Fittings
02-16-2011, 10:10 PM
Those bobstay plates of ours are either 4" or 5" long, and the backstay plate is 8". For your use you'd get them undrilled, or at least not countersunk. But undrilled would allow you to put the holes just where you want them.

I'm not all familiar with any US foundries other than Port Townsend and Bristol Bronze, and I believe some folks have had trouble with BB castings. So I suppose you'd check first with Port Townsend in WA first. It wouldn't be a difficult thing to manufacture, but you might have to pay for the pattern-making. Alternatively, you might find you could adapt a standard chainplate.

Mike

Thorne
02-17-2011, 08:37 AM
http://www.briggsmarine.com.au/images/products/Bobstay-Plate.gif
The main problem with using a fitting like this, attached with screws to the stem, will be when you need to invert the boat for either storage or maintenance. As long as it is on a cradle or soft sand you'll be fine, but if you need to invert it on a hard surface the weight of the boat will come down on that piece of hardware, with much of the force trying to pull the screws out of the wood.

Go with whatever you like --- it is YOUR boat and you need to be happy with it. But do consider how the boat will be used, where it might be inverted and on what surfaces. Small boats are much happier stored inverted, as otherwise they can easily fill with water from torn tarps and get rapidly rotted -- I've seen it happen to a number of 'em at various marinas and boatyards.

Brian Palmer
02-17-2011, 09:20 AM
On a small sail like that I would do the following: Drill a hole throught the breast hook just aft of the stem. Put a small cleat under the breast hook on the inside of the stem. Put a lanyard on the tack of the jib and lead it down the hole and make it off to the cleat. When the sail is not set, there is only the hole in the breast hook and no hardware or holes in the stem. Simple and clean.

Brian

Canoeyawl
02-17-2011, 10:25 AM
http://i1045.photobucket.com/albums/b457/canoeyawl/004-1.jpg

rkeller
02-17-2011, 04:41 PM
What about something like this Davey & Co. Fitting?
With a little photoshopery.

http://i833.photobucket.com/albums/zz254/russ_keller/Cedar%20Strip%20Whitehall/Bowwithplate.jpg

Wooden Boat Fittings
03-05-2011, 02:53 AM
I've just been asked to post an advertisement for a 'Gannet' on our website, and among the photos provided I found this picture of a bobstay plate used at the stemhead as a forestay anchorage point. This is exactly the fitting I mentioned earlier. The builder did a nice job with this boat, and the stem shows it.


http://www.woodenboatfittings.com.au/boats/gannet/gannet5.jpg
Mike