Self-tacking jib experiment - Successful with final photos!

[Stickinthemud57]

Faced with the need to go to an "everyday" jib (see thread "Lite Skin Jib - a mixed bag" https://macgregorsailors.com/forum/view ... 79#p366679), I purchased a 26Lf x24Lc x 8.5F 5 oz Dacron sail. In considering the options among used sails (because dollars) I decided to try the shorter-footed offering, seeing an opportunity to set up a self-tacking jib.

I did not want to deal with the clutter or hassle of permanently-installed tracks or rigging, so have tried to make everything easily set up and removable. Please reference the photo as I explain...

Many self-tackers rely on a deck-mounted track to control the lateral and vertical vectors at the clew. My system uses a boom held down by a removable rope strung between the stanchions on either side and a trim line at the end of that boom, passed through a block car on the mast track, and secured at a rope clutch at the cockpit.

Nothing really new here, except maybe the use of a loosely-strung rope to hold the boom down to help control twist on the jib. Curve will be controlled with an outhaul at the aft end of the boom. Travel port and starboard will normally will be limited by the trim line and ultimately the stanchions, but I'm thinking it may be possible to allow the jib to fly outside the stanchions by removing the hold-down rope. Trim would suffer, but what the hey.

My whisker pole will serve as boom, with the only permanent modification being a small clam cleat for the outhaul.

What say ye, fellow sailors?

Basic self-tack jib plan to post.jpg

[Russ]

Sounds like a plan. Not sure you need the "hold down".

Love the model

Now is this a hank on jib? Seems like a lot of work to setup for just a little gain. I don't mind tacking with jib/genny sheets.

[Stickinthemud57]

Sounds like a plan. Not sure you need the "hold down".

Love the model

Now is this a hank on jib? Seems like a lot of work to setup for just a little gain. I don't mind tacking with jib/genny sheets.

LOL, thanks. It was fun making the model. I cut it 26 cm long to make scaling easy. Started a fun conversation with our cleaning lady.

Yes, it will be a hank-on jib, meant to live in a foredeck bag. It wasn't really much work at all. The model took about an hour and I did most of the fabrication in one evening. I had already planned to add the rail to the mast and the rope clutch and deck organizer. The only other "hard" mod is the clam cleat on my whisker pole which will do double duty as the boom. I made a couple of soft shackles from some spare Dyneema for attaching the tack and outhaul pulley at the clew end to the boom (great tutorial video at https://www.youtube.com/watch?v=aivEI7piLbc. I have plans to make an in-line cleat for the hold-down rope, but that's spare parts and some hacksaw work, so no biggie there either.

I doubt I will use it much if at all when I am sailing alone, and certainly not when racing. There are times when I have passengers (i.e. the Admiral) that it will be more convenient if we have a long upwind run, as I often have to get them/her out of the way to release and haul in the jib sheets. This way they can stay put unless the wind kicks up. This was really more a fun project than anything, and a chance to use some spare parts. I will say this - I would have given a portion of my anatomy for such a rig earlier this year when I found myself single-handing up a three-mile, 350-foot wide channel dead into the wind, tacking every minute or so for close to an hour and a half.

You may well be right about not needing the hold-down rope. I have seen boomed systems without it. In any event, it will be easily removed.

[Be Free]

I'm having trouble visualizing how the trim line runs but otherwise it looks like it should work.

Make sure that your whisker pole can move and twist as needed without damaging the fittings on it. I was careless with mine once while poling out the jib and managed to tear mine up when a gust caught the jib while I was moving it to the opposite side during a gybe. I fixed it but its not as pretty anymore.

[Stickinthemud57]

I'm having trouble visualizing how the trim line runs but otherwise it looks like it should work.

Make sure that your whisker pole can move and twist as needed without damaging the fittings on it. I was careless with mine once while poling out the jib and managed to tear mine up when a gust caught the jib while I was moving it to the opposite side during a gybe. I fixed it but its not as pretty anymore.

I plan to run the trim line between the forward stanchions, or more accurately, between the little braces at the bases so the ends will stay low and not ride up. It will pass over the jib boom, theoretically stopping it at the desired height for proper sail twist when it reaches the nominal trim point. I'm thinking it will also keep the jib from swinging out too far if the trim rope comes loose or is not handled properly.

Thanks for the cautionary note re the whisker pole fittings. Sorry to hear of the damage to yours. Mine are the lightweight plastic kind, so I am especially mindful of potential damage. The plan is to situate things so as to avoid putting stress on the pistons, but no telling how it will behave under stress.

Tracking says the sail will arrive today, so hopefully I will have time to put everything together on the boat and see what's what. Winds will be light and temperatures low in the morning, so maybe I'll be able to take it out for a sea trial as well.

Wish me luck!

[Highlander]

Well curious to see how it works out for u , a few guys on here have tried DIY Jib self tacking set ups with & without a boom, conclusion was that a boom was not really required for small jibs like our,s , I did find a nice set up a few yrs ago that only required one or two lines I think I saved it somewhere lol in one of my computers or external hardrive , would take some time to find lol.
lets us all know the results I,m sure their r a few guy,s who would b interested in this mod

J

[Stickinthemud57]

Sea trials today went as well as I could have hoped! VERY pleased with the results.

What I learned:

-The whisker pole (lightweight forespar model sold through BWY) that I was using for a boom showed a worrisome amount of bowing. Fortunately it did not fail. I will obtain a pole with thicker walls.
-Dyneema (what I was using for the "twist control" that runs athwartships) does not hold well in a cam cleat, especially if it gets wet. That will be replaced with regular line.
-It's possible I may not need the trim line at all. The twist control line, if tensioned properly, prevents the boom and sail from tangling with the stanchions and lifelines. I will need another outing or two to decide whether to keep it or ditch it.

It's possible one could set up a self-tacking jib without a boom, but I am convinced it is necessary if one wishes to have true control over the shape of the sail. One that billows too much simply will not point well, and this rig did surprisingly well in that regard.


A bit more bow than I am comfortable with


I fashioned an in-line cleat, but Dyneema is too slippery, especially when wet. I had to tie it off and could not really adjust it.


Overview of the rig in action


Trim line (red) run to the cockpit


Boom stows easily when not in use

[Russ]

Thanks for posting the update. Looks good.

I'm surprised you got so much bow in the whisker pole.

[Stickinthemud57]

Thanks for posting the update. Looks good.

I'm surprised you got so much bow in the whisker pole.

Thanks!

Yes, the bow surprised (and worried) me as well. I was thinking it would only be subject to compression, but apparently the attachment points at the tack and the clew were off-center enough to distort the pole.

I'm thinking about maybe doing away with the "twist control" in-line clam cleat by tying knots in the Dyneema every inch or so, wrapping it around the base of the stanchion, and jamming it in the inverted "V" where the brace meets the stanchion. A few wraps and a half-hitch or two around the stanchion above the brace should hold everything in place (??).

[PhysicsTeacher]

There are some nice ideas for a do-it-yourself self-tacking jib here:
https://stingysailor.com/2021/01/16/how ... -for-free/

[Stickinthemud57]

There are some nice ideas for a do-it-yourself self-tacking jib here:
https://stingysailor.com/2021/01/16/how ... -for-free/

Thanks! Yes, that was one of the articles I referenced before I started designing and refining mine. Funny, the photo at the top of the article was the one that convinced me I needed to employ some method of keeping the clew from flying up and spoiling the shape of the sail (thus the "twist control" line.

The design I have is performing every bit as good as I had hoped. Minor refinements are all that is needed at this point.

[Highlander]

Thanks for posting the update. Looks good.

I'm surprised you got so much bow in the whisker pole.

Thanks!

Yes, the bow surprised (and worried) me as well. I was thinking it would only be subject to compression, but apparently the attachment points at the tack and the clew were off-center enough to distort the pole.

I'm thinking about maybe doing away with the "twist control" in-line clam cleat by tying knots in the Dyneema every inch or so, wrapping it around the base of the stanchion, and jamming it in the inverted "V" where the brace meets the stanchion. A few wraps and a half-hitch or two around the stanchion above the brace should hold everything in place (??).

Woh that,s a lot of bend in that whisker pole , a good piece of used Alum thick wall tubing would do the trick , looking good keep us posted !

J

[Stickinthemud57]

Thanks for posting the update. Looks good.

I'm surprised you got so much bow in the whisker pole.

Thanks!

Yes, the bow surprised (and worried) me as well. I was thinking it would only be subject to compression, but apparently the attachment points at the tack and the clew were off-center enough to distort the pole.

I'm thinking about maybe doing away with the "twist control" in-line clam cleat by tying knots in the Dyneema every inch or so, wrapping it around the base of the stanchion, and jamming it in the inverted "V" where the brace meets the stanchion. A few wraps and a half-hitch or two around the stanchion above the brace should hold everything in place (??).

Woh that,s a lot of bend in that whisker pole , a good piece of used Alum thick wall tubing would do the trick , looking good keep us posted !

J

Oh, absolutely. My mind was busy figuring out what I would do if it snapped! Yeah, I'm thinking 1-1/2" aluminum tubing with 1/8" walls. Today I pulled into a scrap metal place called "Stinky's" (true) thinking I might luck into what I needed. Nope. Hopefully it will be available locally.

[Stickinthemud57]

OK, here it is in excruciating detail, my finalized self-tacking rig.

From my original post, the mock-up with nomenclature for the ropes and rigging. Per the original post, the twist control rope serves to hold the boom down so as to maintain proper sail twist.


View from side with rigging and rope nomenclature.


Close-up of pivot loop for the trim rope. This is less than ideal as the rope will bend and rub on a starboard tack, but I don't foresee any real problems. Apologies for not getting the jib sheet out of the way.


View from bow. For the boom I ended up using 1.5" aluminum tubing with a 1/8" wall. In retrospect this is overkill. A slightly smaller diameter and/or wall size would probably suffice.


Close-up of tack attachment. I am using quick-release shackles here and elsewhere to simplify set-up and take-down.


Close-up of outhaul also showing trim rope attachment. Outhaul attaches to sail clew with QR shackle.


View from aft


Twist control port attachment. Secured with a Dyneema soft shackle. Super easy to make, no fids required.


Twist control starboard attachment. I threw out the inline cleat and just tied knots in the line at 2" intervals. Stanchion braces provide the perfect pinch point, with remaining rope wrapped and tied to the stanchion above.


There is a potential rub point at the forestay. I'm not terribly concerned about this as the sail will hold the boom away from the forestay when on either tack, but the end will rub when tacking (As long as the boom crosses to the other side. We'll see). It's unlikely the aluminum will damage the stainless steel, but I do plan to fashion a rounded plug for the end to minimize this potential problem.


Trim rope led through deck organizer aft to rope clutch


When not in use, the boom detaches from the clew and is secured at the port stanchion. Come to think of it, maybe better at starboard to keep the trim line a bit more out of the way.


So, there it is. I will update with any tweaks or observations.

[PSNA]

Impressive! Gary Hoyt would be proud.