synthetic stay in roller furler

[seandepagnier]

I recently acquired harken furler mk2, however it uses a 5/8" thread which has a minimum wire rope size 5/16" and my boat is 1/4" in wire rope. Can a 1/4" wire rope can work in a 5/16" sta-lok?

Since this type of furler acts as a turnbuckle and has a locking nut only on the lower left hand thread, what would prevent the top threaded piece from unwinding under tension? Would I have to find a way (drill a hole and insert a pin) or something to lock the top fork of the turnbuckle if I use a synthetic stay?

As for the splice and thimble, would a special type of splice be needed? Since there may not be the same space to make the turn radius large without causing friction when the furler turns, the splice could be spread out over a wider but tighter radius to to the same strength?

[Breaking Waves]

The MKii uses a foil right?

It is not recommended to use a textile stay inside the aluminum foils. There is a decent amount of chafe and rubbing going on inside there and you can not inspect the textile.

[Jim Cate]

Can a 1/4" wire rope can work in a 5/16" sta-lok?

simple answer: NO.

Jim

[seandepagnier]

Originally Posted by Jim Cate

simple answer: NO.

Jim

Thanks, I didn't think so but, if that is the "simple answer" what is the longer answer?

[Orion Jim]

Originally Posted by seandepagnier

Thanks, I didn't think so but, if that is the "simple answer" what is the longer answer?

No, you cannot use 1/4” wire rope in a Sta-lok terminal designed for use with 5/16” wire rope.

[Jim Cate]

Originally Posted by seandepagnier

Thanks, I didn't think so but, if that is the "simple answer" what is the longer answer?

Would you be happy with "Hell no"? Sean, the whole concept of mechanical terminals is that they grip the wire so tightly that it can not slip out of the fitting. The clearances are minimal, wires are forced around a cone shaped "wedge" inside the terminal and no tolerance for changes in wire size is included in the design parameters.

I'm surprised that a smart guy like you doesn't see this instinctively!

Jim

[Kudu]

Time to replace the stay with a nice new stainless one.

[capt jgw]

Originally Posted by Kudu

Time to replace the stay with a nice new stainless one.

Yeah, I'd just pop for a new stay. In fact I did just that a few years back. I found that doing the work myself with Staloks, even at $40 an end, was cheaper than having the rigging shop roll swage the $10 ends in place. It's pretty easy too.
Going up a size shouldn't matter at all, going down not so much.

[seandepagnier]

Originally Posted by Jim Cate

Would you be happy with "Hell no"? Sean, the whole concept of mechanical terminals is that they grip the wire so tightly that it can not slip out of the fitting. The clearances are minimal, wires are forced around a cone shaped "wedge" inside the terminal and no tolerance for changes in wire size is included in the design parameters.

I'm surprised that a smart guy like you doesn't see this instinctively!

Jim

I did see that and as mentioned didn't think it could work. The request for a "long answer" isn't to be told that it can't work but explanations for how to make it work whatever that may require.

The issue is this furler does not have a turnbuckle, instead it functions as one, but as such the threaded part is 5/8" threads. This harken furler mkii I obtained for $250 seems to be set up for a 5/16" wire and I do not wish to use such a heavy wire.

This has nothing to do with replacing the wire: that goes without saying, but how to adapt it. Can I simply buy a 5/8 threaded fork and then use a 1/4" staylok with an eye with a pin to the fork?

[Kudu]

Maybe the answer is sell the furler to someone who has a bigger boat, and see if you can get one which is more suitable. You do not say, but what is your existing system? Hanked on? Photos would also help.

[seandepagnier]

Originally Posted by Kudu

Maybe the answer is sell the furler to someone who has a bigger boat, and see if you can get one which is more suitable. You do not say, but what is your existing system? Hanked on? Photos would also help.

I am using hanked on right now yes.

It is practically impossible and also impractical for me to sell a furler or most anything else. Who would I sell it to? I don't want to try to find someone. It took this guy years to find someone who would give him $250 for it. Yet somehow the price of furler new is very high still. It is clear to me that it really cost much less to produce these things but because of capitalism they are not very affordable.

In any case, I am not going to buy a smaller one for 6 times more cost. A larger furler is probably better anyway for various reasons. I will just have to find a way to adapt it to fit a smaller wire, or I will put a synthetic stay, but I'm concerned the dyneema won't resist twisting like a wire rope and this could be a problem since it screws into the furler.

[Kudu]

A proper furler has many components, not just the drum. That's why it is expensive. A new headstay is just one item, so if that is a problem, I suggest you stay with the hanked-on solution, and fit a down-haul if you don't already have one.

We have a term in Australia for a poorly improvised solution- "bodgy". You could also say dodgy. Such an installation is likely to cause you far more problems than staying with your hank-on system.

[seandepagnier]

Was able to use a metal lathe to make a perfect shim to adapt the 5/16 wire sta lok to support 1/4 wire.

[Jim Cate]

Originally Posted by seandepagnier

Was able to use a metal lathe to make a perfect shim to adapt the 5/16 wire sta lok to support 1/4 wire.

Sean, could you please describe,or better yet sketch your "shim". I can't visualize it yet.

Jim

[fourlyons]

Originally Posted by Jim Cate

Sean, could you please describe,or better yet sketch your "shim". I can't visualize it yet.



Jim

I suspect it's more of what I would call a "sleeve", to make up the difference in diameter. Kind of like prop shaft adapters. As long as it's crushable, or reduce-able, in theory I suppose it should work.