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jarcher

How much purchase for a clue outhaul on a 30 foot boat?

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Like the title says, what do you folks think is the correct amount of purchase for a clue outhaul? Its a Scampi 30, and the outhaul comes out at the bottom of the boom and cleats to the boom. So no winch.

 

Thanks...

 

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No, the line comes out of the bottom of the boom and goes back a few feet to a wing cleat. That's fine. The problem is that the other end of the line goes directly to the clue, and in heavy air the crew is not strong enough to pull it in. So i want to add some blocks inside the boom to help. I want to give them more power but not force them to have to pull and pull forever. So I'm looking for the tradeoff between power and lots of line to pull.

 

So is that 2:1? 4:1? More?

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We have an 8:1 purchase on our 33-footer, mainsail area around 30 square meters.

There is an 4:1 purchase inside the boom (two 2:1 purchases in a cascade), and another 2:1 from where the line exits the boom.

This 8:1 purchase is plenty, we have no problem pulling the outhaul by hand even when going upwind in a blow.

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We have an 8:1 purchase on our 33-footer, mainsail area around 30 square meters.

There is an 4:1 purchase inside the boom (two 2:1 purchases in a cascade), and another 2:1 from where the line exits the boom.

This 8:1 purchase is plenty, we have no problem pulling the outhaul by hand even when going upwind in a blow.

 

Great thanks! I'll start with a 4:1 and see if that does the trick. If not I'll add another 2:1 outside the boom. I like that idea, thanks!

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Since the scampi has a mainsail area of less than 15m2, therefore a 4:1 should be fine right????

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I have 20:1 and 26m^2 with a lower aspect ration than you have. 10:1 wasn't enough. Your plan to start with 4:1 and change it to 8:1 if needed sounds right.

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Since the scampi has a mainsail area of less than 15m2, therefore a 4:1 should be fine right????

 

Sadly, my Scampi is "special." The mainsail area is 192.4^2 feet, or 17.87^meter. Hm, maybe this is the cause of my weather helm problem :-(

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An over-size mainsail can do that. Is it a spar that's bigger than standard? Or Just a lot of roach on the sail?

 

You'll need to find a way to keep the outhaul line clear of fouling anything when it's hanging from the boom...

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An over-size mainsail can do that. Is it a spar that's bigger than standard? Or Just a lot of roach on the sail?

 

You'll need to find a way to keep the outhaul line clear of fouling anything when it's hanging from the boom...

 

It was made in Newport RI, and as near as I can tell, they had a mast kicking around doing nothing so they just stuck it on to this boat. This mast was a good bit taller (18 inches I think - not sure I have to check) then the proper mast, and it was much heavier too. I didn't know when I bought it, or else I probably would not have. This caused all kinds of problems from not being flexible enough to depower to makign the boat pitch like crazy.

 

I have since replaced the mast with one that is the almost identical to the original for weight and such, but I kept the extra height because I didn't want to trash my sail inventory. For this, I not only get extra weather helm but also get to pay a PHRF penality :-(

 

Oh, the outhaul line is not a problem, the crew just sticks it up under itself. I'll bring it back to the cockpit some day, but its only a 30 foot boat so there is always a crew member near the base of the mast anyhow.

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I have a 195 sq. ft. mainsail on my 25' boat, almost the same size as yours but with a longer foot and shorter luff. I wonder if the dimensions affect outhaul load independently of the area?

 

I re-did my outhaul last year. I put 5:1 purchase on it with two double blocks inside the boom. I also turned the line around so it left the boom heading aft and went though a block on a bail after leaving a PXR cleat. This lets the outhaul be tensioned from the cockpit or from the rail. There is less hanging under the boom than one of those H140 blocks. It's detailed on thread here http://forums.sailinganarchy.com/index.php?showtopic=124181#entry3415465 It was originally lead forward though a clam cleat and I found that arraignment to be utter crap.

 

While the 5:1 was enough to adjust under load, you did have to pull pretty hard. I since changed it so that the outhaul no longer shackles directly to the clew ring on the sail. Instead the amsteel outhaul is lead through the clew ring and back to the end of the boom, where there is a convenient tang to shackle it to. That gives an additional 2:1 purchase increasing the total to 10:1. It also halves the load on the rest of the parts, e.g. end of boom sheave and internal tackle. It's now easy to adjust. Since the useful range of sail clew movement is only a few inches one doesn't have to pull too much line.

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Thanks Xyzzy, that looks like a nioce arrangement.

 

Have any of you guys founf that when you have a lot of purchase, you have trouble easing the sail in light air? I am thinking I could do a 5:1 or 6:1 as detailed on Harkin's web site, and then as some have said, if I need to double it I can loop it through the traveler on the clue ans go to the aft end of the boom. But all those blocks make me wonder if it will run okay in light air. I realize Amsteel is pretty thin stuff, but I'm just asking...

 

Oh, and also do you all think the Harken 29mm blocks are sufficient, or will I need to go to the 40mm?

 

Thanks!

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My internal purchase is 1/4" MLX, not amsteel. It's not a cascade purchase but just two double blocks, so whatever line I use there will be the line exits the boom and goes to the cleat. Amsteel is no good for that, too slippery to cleat or hold on to. I think I'd have been better off with a 3/16" line, but it seems none of them are spliceable.

 

For me, the limiting factor for easing the outhaul is the friction of the clew slug in the boom groove. One has to push out the foot of the sail to get it to move the slug even if the outhaul at the clew has slack in it. I think a lot of people use a velcro strap to the hold the clew down, maybe that slides easier, but I have an external reefing system and that interferes with a strap.

 

Even though my outhaul boom sheave and the internal purchase use ball bearing blocks, there is definitely some friction trying to ease the outhaul. So I do wonder about a cascade setup using rings, which have more friction.

 

Originally the internal purchase was with Ronstan RF571 and RF572 single blocks, MWL/BL 330/660 lbs. They apparently lasted just fine for 30 years. I'm now using Harken 29mm bullet double blocks, MWL/BL 400/2000 lbs. No problems so far. The end of boom sheave was a Ronstan RF452, BL 700 lbs. Because the line is turned 180 degrees at the end of the boom, it would take 2x the outhaul load. It was bent out of shape. New boom sheave is a RF31712, BL 1760 lbs. Because the outhaul is looped through the clew ring, it only takes 1x the outhaul load (1/2 load from purchase, then times 2, from 180 degree turn).

 

So 700 lbs BL is apparently not enough for 2x outhaul load on a 195 sq ft main. But 660 lbs BL is ok for 1x the load.

 

You should be ok with 29 mm blocks. The Harken 29mm carbo blocks are rated 660/1625 vs 400/2000 for the bullet blocks. Lower breaking load but higher working load. Kind of odd?

 

For purchase, 5:1 with ball bearing blocks is enough. 10:1 with a cascade is plenty. I would probably go for 4:1 or 5:1, doubled with the loop if I was doing it again. I don't know your deck layout, but for me having the outhaul lead aft instead of forward was a HUGE improvement. Maybe there used to be a gnome who lived in the mast step, and he would adjust the outhaul? Because that's the location it appeared to be meant to be pulled from.

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You should be ok with 29 mm blocks. The Harken 29mm carbo blocks are rated 660/1625 vs 400/2000 for the bullet blocks. Lower breaking load but higher working load. Kind of odd?

 

No, the Harken carbo 29 only have a max working load of 330lbs, breaking load 1.000 lbs:

http://www.harken.com/productdetail.aspx?id=4247&taxid=416

 

I recommend Ronstan orbit 30 blocks, they have a working load of 660 lbs and breaking load of 1.320 lbs:

http://www.ronstan.com/marine/product.asp?ProdNo=RF35101

 

I really like these orbit blocks, we're using them in a lot of places on our boat. Never had one fail yet.

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I'm with those that want as much purchase as possible on the outhaul. You want to be able to make adjustments while going upwind. Consider using a cascade system with Amsteel and your choice of hi tech line you can grip. Block size will depend on when in the system you place them. Load halves at each subsequent cascade. Jam cleats work great as long as the load isn't to great.

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do a search in fix it anarchy for outhaul. its been discussed many times... you could rig a cascade system ...

 

 

but first I would be surprised you don't have some sort of block system in there... I would take the boom end off and take a peek, it's possible that lines are twisted or some such....

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Hi everyone, thanks for all the great information! I agree that the biggest problem to easing the outhaul is the slug in the track along the boom. We tried just using a velcro strap when the sail was brand new and quickly discovered that the attachment point for the main sheet was in exactly the wrong spot, so the slug was added. Perhaps I can move the attachment point, which would allow me to remove that slug. Because yes, as someone said, we do need to push the sail out to ease in light air.

 

As for the thickness of the line, I am trying to figure out how to use nice thin amsteel or something similar in the blocks but use 1/4 inch line where the crew actually has to grab it. It does not look doable. All the systems I have seen have the control line actually running through the blocks. I'm trying to figure out if I can put the 1/4 in control line on the blocks shackle. I suppose I could try to splice 1/4 in to something smaller but I'm not sure that can be done. I could tie the two lines together inside the boom, so the narrow line is tied to the 1/4 inch line, but I know, knots slip and such.

If i use the 5:1 system on Harken's web site:

 

http://www.harken.com/content.aspx?id=3910

 

They recommend two options, the smaller of which uses a Harken 2655 (40mm carbo, max working load 485lb/220kg). As Micha said, the Ronstan 35202 is a 30mm block with a max working load of 450kg, more than double in a smaller package. It is wider, though, because the sheaves are side by side instead of inline. I have a big boom though, it should fit. Of course if my book is big enough, I suppose I could use bigger blocks to make the line run more easily.

As for what's in there already, I'm not sure. It may be a 2:1 but I don't think so, only because the same ratty line that comes out the back of the boom also comes out the front. Although, it could just the the same type of line that aged together.

I'm going to try to get this done this weekend, but I doubt I can get the parts without a drive down to Defender in CT (about an hour). But I just remembered that there is no racing this week, as they always suspend the local club racing for the 4th of July week.

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Those Harken systems look complex and to fit those big blocks you'll need a big boom with lots of space inside. Why not just use a cascade system? 3 blocks will get you 8:1, 4 will get you 16:1, and so on (you have to love exponential growth)...

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You should be ok with 29 mm blocks. The Harken 29mm carbo blocks are rated 660/1625 vs 400/2000 for the bullet blocks. Lower breaking load but higher working load. Kind of odd?

No, the Harken carbo 29 only have a max working load of 330lbs, breaking load 1.000 lbs:

http://www.harken.com/productdetail.aspx?id=4247&taxid=416

 

 

I was comparing double blocks, not singles. They have a load of 660/1625, http://www.harken.com/productdetail.aspx?id=4522&taxid=416

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Those Harken systems look complex and to fit those big blocks you'll need a big boom with lots of space inside. Why not just use a cascade system? 3 blocks will get you 8:1, 4 will get you 16:1, and so on (you have to love exponential growth)...

 

Well, because I don't know how one works, I'll Google...

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Wow, the cascades look more complex than the Harken suggestions. Lots of blocks, but they are singles, so i see that they would be easier to get into the boom...

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Do use a cascade. To get 8:1 purchase, you only need three single blocks. Two inside the boom, one outside. At least that's our system. Very easy and low- friction. As to line, use thin pure Dyneema at the two blocks inside the boom, and thicker line for the last part outside the boom going to the cleat.

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Whats the easiest way to add attachment points to the inside of a boom?

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jarcher, on 28 Jun 2013 - 11:51, said:

As for the thickness of the line, I am trying to figure out how to use nice thin amsteel or something similar in the blocks but use 1/4 inch line where the crew actually has to grab it. It does not look doable. All the systems I have seen have the control line actually running through the blocks. I'm trying to figure out if I can put the 1/4 in control line on the blocks shackle. I suppose I could try to splice 1/4 in to something smaller but I'm not sure that can be done. I could tie the two lines together inside the boom, so the narrow line is tied to the 1/4 inch line, but I know, knots slip and such.

You could just get a strippable line like MLX or warpspeed. Then take the cover off for the part inside the boom. It's pretty common to do this on sheets and halyards.

Quote

They recommend two options, the smaller of which uses a Harken 2655 (40mm carbo, max working load 485lb/220kg). As Micha said, the Ronstan 35202 is a 30mm block with a max working load of 450kg, more than double in a smaller package. It is wider, though, because the sheaves are side by side instead of inline. I have a big boom though, it should fit. Of course if my book is big enough, I suppose I could use bigger blocks to make the line run more easily.

I have a slightly larger main than you, and my boat had weaker blocks than the harken 29 mm for 32 years without trouble... so I really doubt you need the 40 mm.

 

When comparing Harken and Ronstan blocks, keep in mind the breaking load vs working load. Ronstan specifies a working load 1/2 the breaking load, while Harken seems to be in the 1/3 to 1/5 range. I'm not sure if the higher working load rated Ronstan blocks are really any stronger than the Harken ones. I had my spinnaker led through a ronstan orbit 55 ratchet (550 lbs WL) and a harken carbo 40 (485 lbs WL) when the ronstan block exploded. That transferred all the load to the harken block, which held.

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You could just get a strippable line like MLX or warpspeed. Then take the cover off for the part inside the boom. It's pretty common to do this on sheets and halyards.

 

Thats a great idea, I wish i had thought of that! I know exactly what you mean. My had my spinn sheets made this way to reduce the weight of the part of the sheet thats in the air.

 

I have a slightly larger main than you, and my boat had weaker blocks than the harken 29 mm for 32 years without trouble... so I really doubt you need the 40 mm.

 

Thanks for mentioning that. I think what i am going to do this weekend is figure out what size blocks will fit well inside my boom, and get the biggest ones that fit easily. This will then be the strongest set that work, and the bigger they are the easier the lines will run.

 

I'm also still looking at the cascade. I figured out how it would work and I like it, but I think it will be more difficult to rig inside the boom than the simple Harken 5:1 or 6:1 systems on their web site. The biggest benefit I saw in it was that I could easily use a 1/4 inch line for the last part and smaller line for the inside parts, but your idea of using partially stripped line helps with that problem.

 

I also need to inspect the boom this weekend and see how to add an internal attachment point.

 

Decisions decisions...

 

Thanks again!

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I personally don't like to put any more holes in spars and boats than necessary, so I'm a big fan of running a long dyneema strop to the closest hard point on the inside, then attaching all the bits to the strop. Will work with the cascade or the traditional purchase, and will actually be significantly easier than using hardware (think of simply reaching into the boom at the gooseneck, untying the dyneema strop, tying a trace line to it and pulling the entire thing out the other end, instead of screwing with hardware for hours).

 

Only possible issue is fouling with reef lines or any other internal run lines, but as you say, if you have a big boom, shouldn't be an issue.

 

My vote goes for the cascade, you can use smaller blocks that will be lighter, simpler, cheaper and smaller, and ultra easy to add more purchase.

 

Also think about the fact that the clew of the sail will generally only move around 6" so the amount of line on the working end is insignificant compare to a halyard or sheet.

 

Enough drivel! Toss something on, test it, change it, show it!

 

Best of luck.

 

HW

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Leave enough range of motion so you can bend the sail on without struggling to pull the foot tight and unload the shackle.<br /><br />And defiantly consider looping the outhaul through the clew ring and back to the end of the boom. It doubles your purchase basically for free. I'd do that first before having more than two blocks inside the boom. And with the looped outhaul, you can choose to loop it not depending on wind strength.

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So this project is going to suck. The boom is large enough, with the inside dimensions being about 2.5 inches by 2.75 inches. It turns out there is a 5:1 inside there already. Today I pulled the aft end out and was surprised when a double block came out. Everything seemed to run okay, but then it snagged. I don't know if I broke it or if it has an intermittent problem, but either way, I'm going to have to take it apart and see what's going on. I even pulled out the reefing lines (which I have never used) and still it is hanging up.

 

There is a bolt driven through the boom about 1/3 of the way aft that has no apparent purpose. A little further aft is another bolt that holds a bail that the vang is connected to. Or maybe it was the other way around, I was very pressed for time. Its possible the forward bolt is the attachment point for the forward outhaul block and maybe its hanging up on the other bolt. I don't think there is much more in there.

 

I tried to get the boom off the goose neck, but of the six screws holding it in place, I was able to remove, or even turn, exactly none of them.

 

Back to it on Sunday, I can't be without an outhaul :-(

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Many of you suggested a cascade, so I thought about it. Would the design in the attached PDF work? I think this would be an 8:1 cascade (4:1 inside the boom and a final doubler through the clew), is that right? Or is it 16:1?

 

The big advantage of it to me is that it has one attachment point, at the aft end of the boom. I have access there, but not forward.

 

Also:

 

- It lets me use thicker line for the part the crew has to pull

- It lets me use thinner line inside so it can run more easily

- blocks are smaller

- I can add another block easily to double the purchase again

 

Of course I know that the blocks won't int he middle of the boom, but I don't see a problem with them sitting on the bottom unless there is something they can hang up on. There might be, but there is that bolt that goes through the boom. Perhaps the final line (the 1/4 inch one) could go over that. When its loaded, this would keep the blocks and lines above the bottom of the boom and therefore off anything that it could snag on.

 

Thoughts?

 

Thanks!

 

outhaul_design.pdf

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Your Cascades are back to front... you just made it 1:8 not 8:1 (Disregarding the clew double up)

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Your Cascades are back to front... you just made it 1:8 not 8:1 (Disregarding the clew double up)

 

Oh, that can't be good...

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I was just thinking about that yesterday. Mine has a 2:1 inside the boom, which seemed like it was not quite enough over about 10 kts. I mean, I literally had to put down my beer and put a bit of effort into it :angry:

 

Edit: I take that back. After glancing at the manual, I'm no longer sure just what is inside the boom. The drawing makes it look like some complicated gadget with gears and such...

 

outhaul_zpsbbc7f3fa.png

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How about this one? There is no way to do this with an attachment point at the aft end of the boom?

 

Looks ok, but it is already a 16:1 purchase.

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Maybe its a motor with a worm gear!

Really, I think the gears and screw are some adjustment to compensate for sail stretch, but the drawing doesn't look quite right, and doesn't actually show the tackle arrangement.

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How about this one? There is no way to do this with an attachment point at the aft end of the boom?

 

Looks ok, but it is already a 16:1 purchase.

 

Which I realize is quite a bit. I modeled this thing on my living room floor using some string and rings to simulate line and blocks. I removed one block to make the purchase 8:1. To get 9 inches of clew movement I needed 38 inches of pull (which probably reflects a few inches of slack as it should be 36 inches). The attachment point will need to be at least 4 feet and 9 inches forward of sheave at the aft end of the boom.

 

I doubt that my boom is long enough to add a third block and still get 9 inches of clew movement, but I'll go measure everything about the boom this evening.

 

I'm also thinking low friction rings might be a better choice than blocks. I think I can get them smaller with higher working loads.

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This may be one of the moments when you dont actually want a LFR. Loads arent really that high (ive never seen any of the purchase blocks fail on an outhaul), but the friction will be immense.

 

Check the L-36 website for calculations, but I beleive it worked out to taking a 2:1 down to a 1.1:1 purchase if you use rings.

 

They will be less maintenance, but, if youre usinga cascade, itll be easy as anything to pull out and service

 

HW

 

 

 

 

How about this one? There is no way to do this with an attachment point at the aft end of the boom?

 

Looks ok, but it is already a 16:1 purchase.

Which I realize is quite a bit. I modeled this thing on my living room floor using some string and rings to simulate line and blocks. I removed one block to make the purchase 8:1. To get 9 inches of clew movement I needed 38 inches of pull (which probably reflects a few inches of slack as it should be 36 inches). The attachment point will need to be at least 4 feet and 9 inches forward of sheave at the aft end of the boom.

 

I doubt that my boom is long enough to add a third block and still get 9 inches of clew movement, but I'll go measure everything about the boom this evening.

 

I'm also thinking low friction rings might be a better choice than blocks. I think I can get them smaller with higher working loads.

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I think I got it right now. Third times the charm...

 

 

That works. Get some light carbo blocks for the cascade and be done with it. There's no point increasing friction with ferrules in the cascade.

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Cool, what size line would you guys suggest for the inside parts? Defender has AmSteel, 7/64 in (1,600 pounds), or maybe a little bigger at 1/8in (2,500 pounds)? The control line is limited by the sheave, which I am hoping will allow up to 1/4. I forgot to check...

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You can use either of those. Honestly the 7/64 is probably more than strong enough, though you could go with the 1/8 on the piece that goes through the sail to help with wearing. 1/4 should be doable, it's not excessively thick and all but the smallest blocks accept it...

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The bigger amsteel is easier to splice. Harken and Ronstan both makes lashing blocks that you can splice the amsteel to directly. You lose less distance this way since the block is shorter with no swivel and shackle.

 

You'll probably need to take off the gooseneck fitting so you can attach something at the front end of the boom. An advantage of having it at the forward end of the boom is that you can reach it. If you stick something in the middle of the boom, how are you going to reach it?

 

If the bolt you want to put the lines on is threaded, I'd find some way to not have the amsteel rest on the threaded portion. Use a thimble, put a sleeve on the bolt, or get a bolt with an unthreaded shank length, or something. My experience has been that sharp edges are quite effective at chewing through dyneema.

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My first thought was that I'm not going to splice, just tie knots, because the riggers I use all need a week, and I don't have a week. But I just got off the phone with the local guy, New England Yacht Rigging. They won't splice line that I bring them, but he does have a 1/8 in line with a 2,000 breaking strength on hand (I forgot what he said it is). He said if I get it to him tomorrow he can have it done by the end of Wednesday. So I'll go visit him in the morning. He didn't know what blocks he has on hand, but worst case is a drive to Defender, 2 hours round trip to get the blocks.

 

If that does not work, I'll go back to the plan to tie knots.

 

Xyzzy, thanks for the comments on the bolt, I had not thought of that. It looks like a machine bolt so I was thinking it is smooth. If not I'll replace it with one that is or sleeve it.

 

The Gooseneck is not coming off without a good bit of effort. I probably need to drill out the screws, then either retap the holes or drill and tap new ones. I am trying to come up with a scheme using some string to capture the lines over the existing bolt. I think I can do that. If not, then I'll have to deal with the goose neck.

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Just splice it yourself. Splicing eyes in amsteel is super easy.

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Have any of you guys founf that when you have a lot of purchase, you have trouble easing the sail in light air? I am thinking I could do a 5:1 or 6:1 as detailed on Harkin's web site, and then as some have said, if I need to double it I can loop it through the traveler on the clue ans go to the aft end of the boom. But all those blocks make me wonder if it will run okay in light air. I realize Amsteel is pretty thin stuff, but I'm just asking...

 

Thanks!

I did find that easing the outhaul in light air was a problem so I added a bungee cord that pulls the clew ring forward. That might make it a little more difficult to pull the outhaul back but with 20:1 it really is not an issue. You just have to find the right balance. Now when I ease the outhaul, the sail comes forward even in no wind.

 

Allen

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Just splice it yourself. Splicing eyes in amsteel is super easy.

 

With thin Amsteel, it can get a little tricky because the fid doesn't want to go through. Samson says 1/8 is not splicable and 7/64 even less so. I made a soft shackle out of Lashit and splicing 7/64 and 1/8 is easy but you need to make your own splicing wand type fid. Take a piece of stainless rigging wire about 2 feet long and bend it in half. Wind the two ends together and put a bend, maybe 1/2 inch long at the end. This end just keeps the wire from completely going into the core of the Amsteel, something that will become clear as you use it. Use this foot long wire to pull the Amsteel through the splice rather than trying to push the Amsteel through with some more traditional kind of fid. One trick is to taper the last inch of the rope so that half the threads are cut and then put half that amount between the two wires and fold it in half. That way the total thickness you are pulling is the same as the rope diameter. Of course, you thread this wire fid from past where the splice will end toward where the eye will be so it is running through about 11 inches of Amsteel before you pull the end through. I hope this is clear. BTW, with Lashit, you use a very small wire, like a strand out of some multi strand small gauge electrical wire. One more tip -- remember that the outer section will be shorter by about 20% compared to the core so back off a couple of inches and put the wand in there. When you finish, stitch it together. Or, you can make a brummel splice http://L-36.com/brummel2.php

 

Allen

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The smallest tubular fid Samson sells is too big to splice 1/8". But 1/8" is easy to splice with the wire like you say. I use some 28 ga wire for hanging pictures to make the pullers. It's way cheaper than fids too.

 

For the 1.1 mm lash-it, the wire is still too big. For that, I use blunt nosed needle designed for sewing with yarn. I use that to pull a bight of whipping twine through the lash-it, then the twine pulls the amsteel though. When making silly things like loops the size of a quarter, the necessary curve of the loop prevents the needle from going through. So you have to run two lengths of twine though the amsteel while it's still straight, then use them one at a time to bury the ends.

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If your gooseneck is not removable and you need a hard point in the middle of the boom for an outhaul, consider a hole in the front of the boom and a piece of spectra with a stopper knot. You can sew a tail on the line so you can pull it all the way to the clew end for setting up the tackle and then pull it forward as far as you need to and put a stopper knot on. I've found with a dremel and hand files that I can make a smooth hole in metal that won't chafe your line or knot.

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If your gooseneck is not removable and you need a hard point in the middle of the boom for an outhaul, consider a hole in the front of the boom and a piece of spectra with a stopper knot. You can sew a tail on the line so you can pull it all the way to the clew end for setting up the tackle and then pull it forward as far as you need to and put a stopper knot on. I've found with a dremel and hand files that I can make a smooth hole in metal that won't chafe your line or knot.

 

That's an awesome idea, thanks!

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Smoothing the inside of the hole will be tricky, but that's a pretty neat idea. Use a stevedore's knot in the dyneema; it's slippery and knots hold poorly. When I redid my outhaul (link posted earlier) I spliced everything in the entire system except for ONE knot. Guess what part failed.

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Your Cascades are back to front... you just made it 1:8 not 8:1 (Disregarding the clew double up)

 

Oh, that can't be good...

 

Oh, I dunno, think how fit your crew will be.

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I've done a couple of these stopper knot arrangements. I agree it can be hard to smooth the inside but a hand file will do the job, I think. The line is not moving at this point at all once you tie the knot and pull it tight, so if it is smooth enough to allow you to set it up without snagging, I can't see any chafe developing. A bit of tape might help.

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I'm picking up all the parts from the rigger later today! I'll keep this idea in mind as I get to the frustrating part of installing it all...

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You can get a deburring tool, designed for smoothing cut edges and holes. There are bits that are designed to get to the inside edge of blind holes. But they don't really smooth the edge so much as counter sink it. A set of needle files can be had at most hardware stores for a few bucks. The hole could be drilled pointing aft too.<br /><br />Don't make the hole in the boom any bigger than you need to. Stopper knots in amsteel aren't as easy as one might think. The stuff can really squish down under a big load. My big stopper knot turned into a not so big stopper cone.

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From this page , which is talking about something completely different but a stopper knot that has been somewhat tested Might be useful here.

http://L-36.com/halyard_stopper.php

 

halyard_stopper_hs1.jpg

 

This is the stopper end splice. To tie it, fold over the line and tie a diamond knot in the two ends. One being very long but if you tie it the easy way, you only need to pass that through the knot once. Then let the folded over part disappear into the knot leaving just the diamond knot and the two ends out the bottom, one about 60 diameters and the other the rest of the halyard. Finally, bury the short end in the halyard. Don't forget to taper the bury,

 

 

 

Allen

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Its installed! 8:1 cascade with the control line run aft to the pit.

 

Short story, the old outhaul was attached to the forward bolt as I guessed. A friend and I removed both bolts and the old outhaul came right out. That outhaul was a 5:1 system like the first one Harken shows on their web page, with a pair of double blocks, one of which has a becket. The concept was fine, but whoever rigged it managed to twist the line so it bound up on itself. Also, it was attached to the forward bolt so part of it was dragging over the aft bolt.

 

The aft bolt (that holds the bail the vang connects to) was a nice smooth machine bolt and getting the new cascade outhaul attached to it was pretty easy. Just some clever use of string. The aft line which pulls the clew ended up being 3/16, I forgot exactly what the rigger used but it was similar to Amsteel, very strong and low-stretch. It goes through a Ronstan RF25109, a tiny 20mm block with a 550 pound working load. There is another of those inside, with the middle line being 1/8 inch. Finally, the control line is 5/16 in, because I decided to lead it aft where I had an unused line clutch. Now, if the crew needs the winch, its available.

 

It runs just fine, with only a slight tug on the foot of the sail needed to bring it out.

 

Long story is <a href="http://jims-scampi.com/drupal/node/441">here with pics</a>.

 

Thanks to everyone who contributed! All your comments were a great help. It would not have come out so well without all your suggestions!

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