SailNet Community banner

1 - 20 of 26 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter · #1 ·
Hi there,

I'm new to this fourm and I have a question, but first some background. We sail out of Whitby, ON on an H28 Ketch rig. She has a mahogany hull, spruce masts and a furling headsail.

Our wire halyards have all but worn out and we've decided to switch to rope. The sheaves will take a maximum of 3/16"

It was suggested to us that we go with Spectra 12 strand because it's low stretch and high strength. However it's very expensive, approx. $1.30/ft. It has a Minimum Tensile Strength of 3600 lbs.

Novabraid Polyspec has been made as a less expensive alternative but I want to make sure it's strong enough. It has a similar elongation at break strength but only a Minimum Tensile Strength of approx. 1800 lbs.

Does anyone know if this is suitable as an alternative?

Thanking you in advance,
Bobby

Seahorse - H28
 

·
Registered
Joined
·
695 Posts
You might be able to change out your sheeves, 3/16" line is very small. If you go with Spectra it will be strong enough but will be hard to handle. 5/16" is about as small as I would want to use.

If you cannot change out your sheeves you can go with "tapered" halyards. That is one where you have a high tech core like spectra and have a cover on it part way up. This allows a larger line at the deck where you are handling it and the 3/16" core will go though the sheeves.

Gary
 

·
Telstar 28
Joined
·
993 Posts
Before you commit to going with all rope, you really need to do a few things. First, check the halyard sheaves and see if they have a v-shaped or u-shaped groove. If the former, they'll need to be replaced to deal with a rope halyard or they'll chafe it unnecessarily and cause it to wear prematurely. Also, you'll want to check the exit slots for any damage caused by the wire halyard, and repair it so that it doesn't chafe the new rope halyards.

I'd point out that the Novabraid Polyspec is probably a bit weak to replace the halyard, since it has an SWL of about 300 lbs, vs. 600 lbs. for the spectra 12 strand. Shop around, you can get comparable rope to the Spectra 12 strand for less I'm pretty sure.

BTW, the 3/16 stainless wire rope has a tensile strength of about 3600 lbs.. which is a good match to the 12-strand spectra. :)

If you can, as gary points out, go to a larger sheave, so that you can use a larger rope that will be easier on your hands. Or you can use a larger diameter spectra or dyneema cored line, like T-900 and then remove the outer jacket for the section that is in the mast and goes through the masthead sheave.
 

·
Registered
Joined
·
75 Posts
You should also check out this similar thread.

Sheaves used for rope generally have a u-shaped profile to the groove, while sheaves for wire generally have a v-shaped profile to the groove. While you can sometimes use v-shaped wire sheaves on rope, it will tend to cause the rope to wear through faster than if you had the proper sheaves.
You should also inspect your sheaves and boxes for scores, rough spots, and sharp edges. Any of these will damage your new rope halyards.

When sizing your halyard using Novabraid Polyspec you need to go by core diameter, outside diameter. The price compared to Spec-12 will be comparable.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #5 ·
Thanks for all your great advice so far.

I'm not sure if the sheave is v or u shaped as she is in ON and I'm currently in BC.

I really don't want to have to take the masts down again to replace the sheaves either. So I'm hoping that I can find a suitable solution, one that will last at least a few years before I have to rethink.

sailingdog, your advice on the Novabraid Polyspec is exactly what I suspected, but I guess I just needed some reassurance. Perhaps we can go with a tapered line to be easier on the hands.

I'll definitely inspect the sheaves for all 3 haylards as well.

Can't wait to get sailing.

Bobby
 

·
I don't discuss my member
Joined
·
2,557 Posts
I really don't want to have to take the masts down again to replace the sheaves either. So I'm hoping that I can find a suitable solution, one that will last at least a few years before I have to rethink.
Just go up the mast to change the sheaves. Bring a line with you so a buddy can send up the tools.

Check out amsteel in 3/16th. $0.70 / ft and a min. strength of 2300 kg (4500lbs). Easy to splice, UV resistant cover, but I would definitely put a cover over the working/winch/clutch end. Slippery stuff otherwise.
 

·
Registered
Joined
·
5,038 Posts
I wouldn't even consider line as small as 3/16 - it's going to be really hard on your hands when raising the sail. Either change the sheaves to something that can handle a 5/16 line or stick with wire.
 

·
Caribbean Surveyor
Joined
·
511 Posts
If you're shopping around for rope, check out these guys Redpoint Ropes Manufacturing

They are in Midland Ontario, not too far from you and their prices are very good. I changed my wire halyards to rope last year and I believe the price was between $0.95/ft - $1.05. Their work is excellent as well.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #10 ·
I am definitely shopping around for rope, I just don't know which size now....lol

I was hoping to find something in BC while I'm working out here and take it back with me. If I can't find a decent savings I'll definitely send this request off to the local marine supply store and give him the business.
 

·
Senior Mumble
Joined
·
320 Posts
I had a tapered halyard made as described in Gary M's post. Our sheaves were fine, so we've had no problem with that approach. But if you do replace them, it is not hard to do. I removed mine to clean up and lubricate the pin that serves as the axle. They come out easily - mereley remove a cotter pin. IRMV
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #12 ·
I figured it was as easy as that to change the sheaves. I'm sure once I'm up on the bosin's chair I'll find something I didn't think about beforehand.
 

·
Sailing to surf
Joined
·
208 Posts
I am facing a similar situation on my boat. I would like to replace the current hire/rope halyards with all rope, and expect to have to replace the sheave as well. All of the current halyards are so dry rotted that going up the mast on them is a very scary idea.

I feel like my only option is to just replace it with another wire/rope halyard until I can upstep the mast?
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #20 ·
Thanks for all your responses. After LOTS of research and even more great advice here, the missus and I are looking at either this choice.

Amsteel Blue, Winch Line, Rope, ATV winch lines

It's a Canadian Manufacturer which is a plus as well.

Or someone local in BC that I can pick some Spectra from while I'm still here.

Looks like we're taking the advice here too. We're going to change the sheaves to probably accomodate a 5/16" 12 strand line.

So that means up the bosins chair to measure and take out existing sheaves. Over to the local Marine Supply store to buy said sheaves. Back up the bosins chair to install those newly purchased sheaves and then ready for the halyards.

Thanks for the make work project everyone ;)

No really....thanks !

Cheers,
Bobby
 
1 - 20 of 26 Posts
Top