jib car eliminator

[Dockhead]

Originally Posted by Snowpetrel

DH, sounds like you need one of those ronstan Constrictor clutches

Hot tip; thanks. That would work like a dream -- just fix the lanyard to a stanchion with a little small stuff, and operate it with a boat hook

$300 a pair; yikes!

[Dockhead]

Originally Posted by mrlee

I want to change over to this set up (pic) but I have a few questions... My present track is about 40 inches or so long, How long should these individual pieces be and exactly where do I secure them to my boat? Half track? a little more forward....behind?
Thanks in advance to you all...I appreciate the skillful advice here...

Concerning the location -- you have to work it out according to the range of sheet lead angle you need.

It will need to be somewhat forward of the front of the track since you will not be able to get the blocks as close to the deck as the track does.

Assuming you're happy with the angles of the present track, I would measure the sheet lead angle all the way forward and all the way back, then go from there.

Note that if you put the system on the rail the way I have it, the sheet lead will be too far outboard for sailing close hauled.

I use my staysail sheet (self tacking staysail) as an inboard twing. I can then adjust the sheet lead inboard and outboard by balancing tension between inboard and outboard twings. This way I can also sheet inside the shrouds, but you need a second pair of sheets to make this work well.


One more tip about this system -- be careful not to keep winching after you reach the end of the end of the range of travel. Stuff will break. Don't ask me how I know . A good idea to sew red yarn into the control line at the point of the end of travel, so you immediately see it at the winch, as a reminder.

[Cruisingscotts]

Originally Posted by Dockhead

Hot tip; thanks. That would work like a dream -- just fix the lanyard to a stanchion with a little small stuff, and operate it with a boat hook

$300 a pair; yikes!

I've heard smaller boat race boats use them at the mast head on halyards to eliminate mast compression. Lot of faith in the lanyard letting go there.

[Stumble]

Below is a pretty good example of how this can be retrofitted. If a clean instal, then you just move the 'twing' as far outboard as possible, and eliminate the entire jib track and car equipment.

Depending on the sail you may also need to have the foot recut to lift it off of the deck a few inches to give enough room to develope the leech loads necessary to fly the sail properly.

[mrlee]

Wow, so many great ideas...now to the drawing board...I like the inhaul idea a lot...I'll let you all know what I do...thanks a million...
OH, I made the rings with nylon...it;s plenty thick and I am hoping strong...what do ya think?

[Snowpetrel]

Originally Posted by Dockhead

Hot tip; thanks. That would work like a dream -- just fix the lanyard to a stanchion with a little small stuff, and operate it with a boat hook

$300 a pair; yikes!

I wonder if you could just relocate your existing clutches onto the cockpit coaming? And lead the lines through a turning block near the rail. I guess its one more thing to trip over.. Unless you could find a cunning lead aft or something.

Those constrictor clutches can have the release line extended so you wouldn't need the boathook :thumbup: but I have heard of some issues getting them to grip without milking the cover over them in some highly loaded small diameter lines?

Maybe you could sell a few of those electrical gadgets and buy the textile clutches

[Dockhead]

Originally Posted by Snowpetrel

I wonder if you could just relocate your existing clutches onto the cockpit coaming? And lead the lines through a turning block near the rail. I guess its one more thing to trip over.. Unless you could find a cunning lead aft or something.

Those constrictor clutches can have the release line extended so you wouldn't need the boathook :thumbup: but I have heard of some issues getting them to grip without milking the cover over them in some highly loaded small diameter lines?

Maybe you could sell a few of those electrical gadgets and buy the textile clutches

Thanks -- I could put the clutches at the cockpit, but then (a) I would have to drill holes in it, and I HATE to drill holes in any part of the boat which is supposed to keep water out; and (b) the tensioned control lines would stretch across my side decks and be a trip hazard.

I think those textile clutches would work fine, and because of all the purchase the control lines aren't that highly loaded. At the moment hard to justify the expense, though. Hmmm.

[Dockhead]

Originally Posted by mrlee

Wow, so many great ideas...now to the drawing board...I like the inhaul idea a lot...I'll let you all know what I do...thanks a million...
OH, I made the rings with nylon...it;s plenty thick and I am hoping strong...what do ya think?

Lot of friction there with the lines running in and out when you tack. I doubt plastic will last long in that application, and I would also be skeptical about whether it's strong enough.

You really want something like the Antal Low Friction Ring, like in the photograph.

Also, don't use a simple ring like what is shown in the drawing -- pulling a heavily loaded rope over a small diameter ring will damage the rope and reduce its strength. You want a certain ratio between the diameter of the sheave or virtual sheave and the diameter of the rope.

[Stumble]

Originally Posted by mrlee

Wow, so many great ideas...now to the drawing board...I like the inhaul idea a lot...I'll let you all know what I do...thanks a million...
OH, I made the rings with nylon...it;s plenty thick and I am hoping strong...what do ya think?

To agree wth Dockhead, no, Nylon rings will not work. I haven't don't the calculations, but I would guess you are trying to contain ~1,000-1,500lbs of load in that ring, possibly more. Nylon simply won't hold.

Low friction rings are not really expensive and work very well. The downside to them is they really need to used with uncovered dyneem to keep. The friction down. It isn't a real issue but it really would require upgrading your sheets.