Runners & backstay - blocks vs rings?

[andreas.mehlin]

I'm replacing all my rigging and will probably go with dyneema.
For runners and check stay I also need to update the purchase systems 4:1. For backstay (y-parted)...purchase? (46 ft trimaran)

The question is. Simplicity with rings vs fiddle blocks?

[admiralslater]

I think it depends on the load ,the angle attack and how much adjustment is needed under load .
I am going to use them on some spinnaker gear where once set they dont move .
A friends Outremer 45 had one fitted by the factory as a turning block with an angle of about 130 degrees. The sail almost could not be adjusted in strong winds .
I raced on a hobie 33 which was owned by a professional rigger . The rings where only used to as tweakers on sheets etc never in high load and or movment situations .

[SailRedemption]

We used NER dyneema running backstays that terminate with a large ring. We have NER VPC line that starts at a padeye at the deck, goes through the ring, to another padeye aft of the first, then to the secondary winch. At some point we'll get clutches for them. I'll try to take a picture when I get to the boat.

[-bliss-]

For your back stay, its not either blocks or rings. In my experience, a combination of the two is the best compromise when converting to dyneema backstay. As it happens, I made a conversion for a neighbor in my marina earlier this week. He is racing his family cruiser on a regular basis, and he wanted the ability to trim his backstay as much as possible, without starving the wife and kids. So instead of using fancy roller- and ball bearing blocks, we ended up making three bridles using three low friction rings (8:1) and then adding a pair of inexpensive fiddle blocks for additional 4:1 purchase in the bottom, which resulted in a total of 32:1 purchase. A very light weight, low maintenance, low friction and affordable solution. Use slippery quality single braid dyneema through the rings and double braid polyester through the fiddle blocks. 16:1 should be plenty for a regular cruiser, but make sure to put the rings quite high up in the backstay. Otherwise you risk not getting enough play for the 4:1 in the bottom if you later on want to add another purchase...

For runners and check stays, I recommend as little purchase s possible down to deck if you have dedicated winches for the task. The primary goal of this approach is to have as little rope as possible to handle. Releasing leeward runner all the way down to deck (safely away from your teeth) and tightening it back again when you´re on the other tack, is way faster with a 2:1 purchase, and you don’t end up with too much line cluttering your cockpit when the runner is tightened. If you don´t have dedicated winches, you obviously need way more purchase.

A common solution for the check stay, is a 4:1 purchase (becket fiddle cleat in the bottom, and fiddle on top) on the bottom of the stay, where it is connected to the runner. On my boat I duplicated this original solution when switching to dyneema, but the cleat on the becket fiddle block wasn’t able to securely hold the new and thinner line, so I simply added a piece of dyneema and a low friction ring to double the purchase (now 8:1), hence cutting the force required to hold the bitter end in half. It also made adjustment so much easier. In this application you don’t need more than a couple of inches of play anyway, so even though you have to pull twice as much line to adjust if accommodating this 8:1 solution, the difference it barely noticeable. After four seasons, I´m happy to say it turned out great, and I´ll strongly recommend this approach. As I have dedicated winches for my runners, I only have 2:1 down to deck. Less rope to trip on, and faster adjustment.

I might be able to make an illustration or add a photo or two if needed.

Good luck to you. The Brummel splice is easy, and as we all know, it´s great fun pimping your boat, when it can be done without ruining the budget..

-kjetil-

[Benz]

My runner tails go through one ring with a 180 degree turn, and another with a 90 degree. I have to use my dedicated winch to get anything like decent tension. I will upgrade to the best blocks I can afford as soon as I can afford to (read: as soon as I find some good stuff on the clearance rack). Rings are the best thing since sliced bread, but sometimes you just need a good bearing block.

[-bliss-]

Just a little clarification to sort out some possible confusion, and hopefully fill in the gaps between Benz´s post and my own.

The low friction rings are immensely strong. They are inexpensive and light weight, and they are easy to DIY as soon as you master the splicing needle. However, they add a little more friction than the appropriate block.

My rule of thumb is to use these rings for heavy (more or less) static loads,
fancy ball bearing blocks for light dynamic loads that require frequent adjustment, and sturdy roller bearing blocks for heavy dynamic loads. It´s all about your budget, I guess. Personally, I´m never in a hurry, I tend to favor reliability, and don't mind a little friction. How much friction you experience while hauling the bitter end, is also a result of how much purchase you build into your system, and what kind of line you run through the rings. Single braid dyneema, is pretty slippery stuff. It´s also very strong, so we can safely downsize one dimension in the applications where we previously used poly line, which certainly helps to reduce the relative friction through the block or ring..

However, if you are willing to spend the big bucks and don't mind the extra weight, go get the roller bearing blocks.

The only disadvantage of the LFR in my opinion, is the inability to rig them on an already loaded line (for instance to alter genoa sheet angle while sailing), so the money you save by using rings instead of fancy blocks, can buy you a nice pair of snatch blocks for those occasions.

There's no right or wrong here. All I can say for a fact is they are sturdy, light weight and inexpensive. It´s all about your personal preferences, I guess.

Good luck!

-kjetil-

[Dmeistar]

Originally Posted by -bliss-

For your back stay, its not either blocks or rings. In my experience, a combination of the two is the best compromise when converting to dyneema backstay. As it happens, I made a conversion for a neighbor in my marina earlier this week. He is racing his family cruiser on a regular basis, and he wanted the ability to trim his backstay as much as possible, without starving the wife and kids. So instead of using fancy roller- and ball bearing blocks, we ended up making three bridles using three low friction rings (8:1) and then adding a pair of inexpensive fiddle blocks for additional 4:1 purchase in the bottom, which resulted in a total of 32:1 purchase. A very light weight, low maintenance, low friction and affordable solution. Use slippery quality single braid dyneema through the rings and double braid polyester through the fiddle blocks. 16:1 should be plenty for a regular cruiser, but make sure to put the rings quite high up in the backstay. Otherwise you risk not getting enough play for the 4:1 in the bottom if you later on want to add another purchase...

For runners and check stays, I recommend as little purchase s possible down to deck if you have dedicated winches for the task. The primary goal of this approach is to have as little rope as possible to handle. Releasing leeward runner all the way down to deck (safely away from your teeth) and tightening it back again when you´re on the other tack, is way faster with a 2:1 purchase, and you don’t end up with too much line cluttering your cockpit when the runner is tightened. If you don´t have dedicated winches, you obviously need way more purchase.

A common solution for the check stay, is a 4:1 purchase (becket fiddle cleat in the bottom, and fiddle on top) on the bottom of the stay, where it is connected to the runner. On my boat I duplicated this original solution when switching to dyneema, but the cleat on the becket fiddle block wasn’t able to securely hold the new and thinner line, so I simply added a piece of dyneema and a low friction ring to double the purchase (now 8:1), hence cutting the force required to hold the bitter end in half. It also made adjustment so much easier. In this application you don’t need more than a couple of inches of play anyway, so even though you have to pull twice as much line to adjust if accommodating this 8:1 solution, the difference it barely noticeable. After four seasons, I´m happy to say it turned out great, and I´ll strongly recommend this approach. As I have dedicated winches for my runners, I only have 2:1 down to deck. Less rope to trip on, and faster adjustment.

I might be able to make an illustration or add a photo or two if needed.

Good luck to you. The Brummel splice is easy, and as we all know, it´s great fun pimping your boat, when it can be done without ruining the budget..

-kjetil-

I would love to see an illustration or photo of this! I need to replace the running backstays on my cruising sailboat and am looking for an inexpensive and simple solution. Thanks!

[fxykty]

Originally Posted by Dmeistar

I would love to see an illustration or photo of this! I need to replace the running backstays on my cruising sailboat and am looking for an inexpensive and simple solution. Thanks!

2:1 running backstay purchase using Colligo Enhanced Static Lashing Blocks instead of
expensive roller bearing blocks and 12mm Dyneema core line with cover removed where it goes around the rings. The bare Dyneema easily slides around the rings.

We needed high load (SWL is 3500kg), but if you need less than that you could use regular low friction rings.

LFRs and Dyneema rope are not inexpensive, but they are much cheaper than blocks with bearings. In our case the blocks were over $1,500 each, while our entire purchase system cost $300 (including shipping from Colligo in the US to NZ).