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Old 01-04-2009, 17:24   #1
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Anchor set-up question.

A question about anchoring with the current setup plus what I want.

Gemini 105Mc
9000lbs - factory
estimated 10000-11000 lbs loaded.

It now has:
Delta (lbs-?)
40' HT chain (1/4 in I think - looks puny)
250 ft rode.

To set up a bridle (20ft each leg) using what I want is that plate that has the slots cut into it. If I use 30ft of chain and then hook it up to leave me 10ft for the lazy loop then at 5:1 I can only anchor in water up to about 7ft deep.

Then it turns to the nylon rode.

If I have the plate setup on the bridle then what is the best way to easily switch over to some sort of rope to bridle attachment? I don't really want to have two separate bridle setups.

Would a simple loop of some sort work? - Nah = chafe.
Remove plate and tie both bridle ends each time? - Pain to remove two seized shackles..........and what about the thimbles?

Hmmmmm.................
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Old 01-04-2009, 18:19   #2
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Anchoring is like religion - you'll get lots of comments!

Quote:
Originally Posted by Therapy View Post
A question about anchoring with the current setup plus what I want.

Gemini 105Mc
9000lbs - factory
estimated 10000-11000 lbs loaded.

It now has:
Delta (lbs-?)
40' HT chain (1/4 in I think - looks puny)
250 ft rode.

To set up a bridle (20ft each leg) using what I want is that plate that has the slots cut into it. If I use 30ft of chain and then hook it up to leave me 10ft for the lazy loop then at 5:1 I can only anchor in water up to about 7ft deep.

Then it turns to the nylon rode.

If I have the plate setup on the bridle then what is the best way to easily switch over to some sort of rope to bridle attachment? I don't really want to have two separate bridle setups.

Would a simple loop of some sort work? - Nah = chafe.
Remove plate and tie both bridle ends each time? - Pain to remove two seized shackles..........and what about the thimbles?

Hmmmmm.................
And a lot of things will work fine. Chafe, all links the same SWL, scope, bridle.

  1. 5:1 is really short, IMO. 7:1 is the standard for setting; then you can shorten up. So, water to about 5.5 feet, which can be thin even for you, if there is tide to consider. Realistically, you are going to be tying to the fiber portion sometimes. But I am in you position and what you describe works. I have the same weight and gear.
  2. Use a 22' line to the other bow and attach it to the fiber rode with a rolling hitch; no chafe, except where the 2 lines go through chocks. You need to protect that. Alternatively, if the rolling hitch bothers you, you can use a prussic hitch at the end instead of a rolling hitch (they are very similar knots, one tied with the end of a rope, the other with a loop). I have done this too. Easy, simple, and reliable, though tying the rolling hitch while leaning over the bow can be troublesome if the wind is up. The advantage of the prussic loop is that you can attach it to the rope on deck, let it go through the roller, and quickly clip it on the other side, even if it is blowing (Mammut Dyneema Contact Sling at REI.com).
  3. Alternatively, use a bridle with fiber too, probably with a prussic knot. In my case I added a hole for that purpose (Sail Delmarva). If using a plate without the hole, you can attach the loop to either shackle, but then the plate will see a stress it is not meant for... Though I think with your boat it is not going to be the weak link. There are many possible chafe points, so...
  4. Simply have 2 single-purpose bridles; one fiber, one chain. That can be simplicity itself; 50' of 5/8" line with loops in each end and the center formed with figure-8 knots (the line is strong enough that the 20% knot loss does not matter). Slide some chafe gear over the center loop and skip all of the thimbles and shackles and failure points. Splice the ends, if you like neat, but the strength is limited by the center knot. I used this rig for 15 years on my last boat.
Have fun!
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Old 01-04-2009, 20:11   #3
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Quote:
Originally Posted by thinwater View Post
And a lot of things will work fine. Chafe, all links the same SWL, scope, bridle.

  1. 5:1 is really short, IMO. 7:1 is the standard for setting; then you can shorten up. So, water to about 5.5 feet, which can be thin even for you, if there is tide to consider. Realistically, you are going to be tying to the fiber portion sometimes. But I am in you position and what you describe works. I have the same weight and gear.
  2. Use a 22' line to the other bow and attach it to the fiber rode with a rolling hitch; no chafe, except where the 2 lines go through chocks. You need to protect that. Alternatively, if the rolling hitch bothers you, you can use a prussic hitch at the end instead of a rolling hitch (they are very similar knots, one tied with the end of a rope, the other with a loop). I have done this too. Easy, simple, and reliable, though tying the rolling hitch while leaning over the bow can be troublesome if the wind is up. The advantage of the prussic loop is that you can attach it to the rope on deck, let it go through the roller, and quickly clip it on the other side, even if it is blowing (Mammut Dyneema Contact Sling at REI.com).
  3. Alternatively, use a bridle with fiber too, probably with a prussic knot. In my case I added a hole for that purpose (Sail Delmarva). If using a plate without the hole, you can attach the loop to either shackle, but then the plate will see a stress it is not meant for... Though I think with your boat it is not going to be the weak link. There are many possible chafe points, so...
  4. Simply have 2 single-purpose bridles; one fiber, one chain. That can be simplicity itself; 50' of 5/8" line with loops in each end and the center formed with figure-8 knots (the line is strong enough that the 20% knot loss does not matter). Slide some chafe gear over the center loop and skip all of the thimbles and shackles and failure points. Splice the ends, if you like neat, but the strength is limited by the center knot. I used this rig for 15 years on my last boat.
Have fun!

Thanks for all that.
Trouble is I cannot see it in my head.
I will draw it out on paper sentance by sentance and see if it makes any sense. Not today though.
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Old 07-04-2009, 18:11   #4
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With only 30 feet of chain, why bother with the chain attachment? You're only going to be on chain in fair weather and shallow water so no chafe worries. In severe weather you should have more scope (don't forget to add your 2-3 foot bow height to your scope calcs, so you have even less scope than Thinwater pointed out). My bridle lines are stainless attachments at the boat and a rolling hitch for each bridle line at the rope or chain. These can be done right at the bow as the rode is let out, then after tying I let it out more until the bridle takes the load. Never seen any chafe at the chain either, as it doesn't slide. I use 40-feet of chain and usually attach to rope portion of the rode. If we're just stopping for an hour or two and it's not blowing hard we don't even bother with the bridle.
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Old 09-04-2009, 07:03   #5
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All true, but cats do have one diffierence -

Quote:
Originally Posted by SailFastTri View Post
With only 30 feet of chain, why bother with the chain attachment? You're only going to be on chain in fair weather and shallow water so no chafe worries. In severe weather you should have more scope (don't forget to add your 2-3 foot bow height to your scope calcs, so you have even less scope than Thinwater pointed out). My bridle lines are stainless attachments at the boat and a rolling hitch for each bridle line at the rope or chain. These can be done right at the bow as the rode is let out, then after tying I let it out more until the bridle takes the load. Never seen any chafe at the chain either, as it doesn't slide. I use 40-feet of chain and usually attach to rope portion of the rode. If we're just stopping for an hour or two and it's not blowing hard we don't even bother with the bridle.
You always need a bridle. Even if the weather is fair, the zigging tied to only one hull is too much. A tri is differernt, not doubt. Tying to center at those times would be easy.

He is right about the lack of chafe tieng line to chain. Many do it that way. I made the chain plate for my cat, in large part, because it was winter and I was bored . Gotta have a boat project - it's either that or paint the kid's bedroom.

Even if you can find a place to tie to a the center of the Gemini, I wouldn't do it; ther are to many ways to bend or break something. Your reacher track comes to mind.
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Old 09-04-2009, 08:35   #6
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For our PDQ 36 which was very similar to your Gemini in anchor chain setup we always let out our 30 ft of chain, always, then simply tied rolling hitches to make a bridle to the rode coming back to the bows. So, if you were in shallow water, we'd dump all the chain, then secure the bridle just after the chain. In deep water, dump the chain down and then count out however much rode you need for 7 to 1. Rode to rode with a proper hitch never showed any wear.
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Old 09-04-2009, 13:14   #7
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Quote:
Originally Posted by schoonerdog View Post
For our PDQ 36 which was very similar to your Gemini in anchor chain setup we always let out our 30 ft of chain, always, then simply tied rolling hitches to make a bridle to the rode coming back to the bows. So, if you were in shallow water, we'd dump all the chain, then secure the bridle just after the chain. In deep water, dump the chain down and then count out however much rode you need for 7 to 1. Rode to rode with a proper hitch never showed any wear.

I suppose I will do this, except when I am in 3ft of water for the night, HeHe!
Then I can just tie to the chain.

It seems as though I was over-complicating things - I can do that well!!

Thanks to all
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