[C320-list] Reefing system project

Tue Jun 25 07:41:06 PDT 2013

This is a nice write up. I use the same system but without the blocks on 
the sail, and I like it a lot. Also, my boat has a padeye on the mast 
next to the gooseneck that I use to terminate the forward line rather 
than taking it down to the base of the mast.

Some advantages of the system over "traditional" single line systems 
(with one continuous line and no shuttle block) are:

1. It's very easy to derig and remove the main. Just untie one line at 
the end of the boom and another at the mast and you are done. There is 
no need to unreeve the reef line from the sheet stopper in the cockpit 
to free up the tack.

2. Reduced friction even if no blocks are added to the sail. With a 
traditional single line system you need to pull 4 feet of line through 
the forward reef point for every one foot that you lower the sail. With 
this system the 4 feet is reduced to 2, cutting friction at the forward 
reef point in half. (I've heard some argue that the shuttle block itself 
adds friction, but that is negligible compared to the friction from 
extra line running through the forward reef cringle.) Personally, I've 
never felt a need to add the blocks to the sail. I find that with this 
system usually I can reef the sail pretty easily even without those 
blocks, provided I luff the main completely, ease the vang, and dump the 
halyard sufficiently.

Not all methods of using the shuttle block give these advantages. For 
example, the second reefing system on the "alternative reefing systems" 
document at the web site uses the shuttle block but with the forward 
line terminated inside the boom. The shuttle block in that system offers 
neither of the advantages mentioned above, and has all of the 
disadvantages of a traditional single line system, plus added friction 
from the shuttle block.

Scott Thompson
Surprise, #653

On 6/24/2013 11:43 PM, Doug Treff wrote:
> When we purchased September Song (Hull #350) last August, the previous 
> owner had not rigged any reefing system at all. After a few white 
> knuckle moments where the boat kept rounding up due to being 
> over-canvassed in high winds - we once rounded up so hard that the 
> boat tacked unexpectedly - I decided it was high time that I get the 
> reefing system sorted out.
>
> While doing my research on the factory setup, I discovered that the 
> OEM supplied internal block inside the boom was nowhere to be found on 
> the boat. At that point, since I would be buying all new components, I 
> decided to compare all the different reefing systems out there on the 
> C320 site along with other single-line reefing systems that I found 
> and come up with something that is easy to operate and not terribly 
> expensive. One of the things that concerned me was that with the 
> factory arrangement, there was potential for a considerable amount of 
> friction because of the line sliding through the aft reef point.
>
> The first order of business was to research the factory reefing 
> system. The Association web site was very useful in this regard. Not 
> only do they have a complete owners manual with diagrams of the 
> factory setup, there is also a chart containing the (almost) correct 
> line lengths for the factory system. I also searched the technical 
> photos section of the site and found Jeff Hare's interesting mod to 
> the factory setup where he added ball bearing blocks on the sail at 
> the reef points to reduce friction.
>
> While searching for a suitable replacement for the internal boom 
> block, I contacted Sparcraft-US (formerly Charleston Spar) who made 
> the spars for my boat. I spoke with Robert Quates, who has been with 
> them for nearly 30 years. One of the reefing arrangements that I had 
> been considering was a single line arrangement that I found on 
> Sparcraft's web site. It looked simpler than the Catalina arrangement 
> because the internal block was not used. I was actually leaning 
> towards using that arrangement when I called him. We had a very long 
> and detailed conversation and Robert provided me with some really good 
> advice. It turns out that he actually prefers the Catalina factory 
> arrangement because the floating block in the boom causes the sail to 
> be pulled down evenly as the reefing line is tightened. The problem 
> with the single line system on the Sparcraft site (without the 
> floating block) is that one reef point usually tightens first and then 
> the other one tightens up. This results in uneven pulling on the sail 
> cloth and sometimes an issue where things bind up and never pull up 
> straight without someone going up on deck to assist. That kind of 
> defeats the purpose of the single line system. When the wind pipes up, 
> the safest place to be is the cockpit.
>
> Once he convinced me to go with the factory line routing, he 
> recommended some improvements to eliminate friction and make it work 
> more smoothly.
>
> First of all, he suggested that I NOT try to buy an exact replacement 
> for the internal boom block. Robert said that this block is only a 
> delrin sheave over a Stainless steel shaft with no bearings. Over time 
> these sheaves will bind and not spin freely, which adds friction to 
> the system. Robert suggested that I instead buy a couple of high 
> quality ball-bearing blocks - the non-swivel or locking type to reduce 
> line twist in the boom - and connect them end to end by their 
> shackles. These will perform the function of the missing OEM part 
> while significantly reducing friction. He also recommended that I add 
> blocks at the fore and aft reef points on the sail. These blocks 
> should be the swivel type. This turns out to be similar to Jeff Hare's 
> arrangement that is found on the association web site. The line 
> routing is exactly like the owners manual diagram except that I added 
> a swivel block to the forward reef point and secured the bitter end at 
> the base of the mast. Because of this, I added 6 feet to the factory 
> specified length listed in the rigging schedule in the owners manual.
>
> Robert told me that with the addition of ball bearings in the boom, 
> and the additional purchase gained by adding a block on the forward 
> reef point, my reefing system will be nearly effortless. He was right! 
> It should be noted that Robert convinced me to do all this and 
> actually didn't earn a penny for Sparcraft. He's a great resource!
>
> Now that I had the basic plan, it was time to collect the necessary 
> parts. A basic parts list follows:
>
> Qty 4 - Harken 57MM Carbo Air block swivel P/N 2600
> Qty 1 - Suncor 1.25" Welded SS Ring PN: C0139-0630
> Qty 20 feet - Aft reefing line - 5/16 diameter low stretch
> Qty 60 feet - Forward reefing line - 5/16 diameter low stretch
>
> First, I took two of the air blocks and locked their swivels so that 
> they would not twist the line inside the boom. I connected them end to 
> end by their shackles. This assembly replaces the OEM internal boom 
> car that is supplied with the C320. Since there was no reefing line 
> rigged in my boom at all, I used a metal plumbers tape to feed the 
> forward reef line from the gooseneck back to the aft end of the boom. 
> Upon exiting the boom, I took the end of the line and passed it 
> through one of the sheaves of my new "car" assembly. Next, I fed the 
> aft line through the other sheave on the car assembly, and routed it 
> through the block that was to hang on the aft reef point. I secured 
> that block to the reef point by passing its shackle through the port 
> side of the aft reef grommet in the sail and capturing the 1.25" SS 
> ring on the starboard side. This ring provides a way to connect the 
> block to the sail with no sharp edges. Ones that was done, the bitter 
> ends of the line are made fast. One of them is tied through the 
> grommet below the reef point and around the boom. The other end is 
> passed through the small hole in the aft end of the boom from the 
> inside and made fast with a figure eight knot. Finally, I routed the 
> remaining end of the forward line back through the boom with my 
> plumbers snake once again, exiting the bottom of the boom at the 
> gooseneck. This forward line is routed up down trough the block on the 
> vang attachment and then up through the final swivel block at the 
> forward reef point and then passed down and tied off at the base of 
> the mast. The forward block cannot be attached to its reef point with 
> a SS ring because the stock sail from Catalina has a smaller grommet 
> in this reef point. I used a short length of reefing line, tied in a 
> knot on the back side of the sail and the block is tied to it. This 
> forward block arrangement is the only deviation from the routing of 
> the lines in the factory diagram.
>
> When all this was done and I tested the system, the aft reef point was 
> not pulling down tight to the boom. After some experimentation, I 
> untied the end of the aft line and shortened it by about 2 feet. Once 
> I did this, it worked flawlessly. The only thing I can think is that 
> adding the extra block forward changed the dynamics of the system and 
> required some adjustment in the aft line to make up for it.
>
> My main halyard is on the starboard side, so I routed the control end 
> of the reefing system to the port side so I could have both lines on a 
> winch at the same time if necessary.
>
> My reefing procedure goes like this:
> 1. Ease main sheet so main is luffing
> 2. Lower main halyard until reef point comes down to the boom. I 
> marked the halyard with a black sharpie so I would know approximately 
> how far to lower it.
> 3. Move to port side and take up the slack in the reefing system. 
> Cleat off once tensioned.
> 4. Move back to halyard and tension as necessary.
> 5. Optionally tie off lines hanging in intermediary reef points to 
> bundle loose sail. Be careful not to tie them too tightly. They are 
> not meant to take wind loads, only bundle the sail. If tied too 
> tightly, they could rip from sail.
> 6. Trim main sheet and you're done!
>
> This whole procedure can be done in about 2 minutes after a few 
> practice sessions.
>
> Shaking out the reef is very similar. Luff the sail, then follow the 
> above steps in reverse order.
>
> I am very pleased with the new system and the setup is quite 
> effortless to operate. The use of ball bearing blocks everywhere has 
> contributed greatly to the system working so smoothly. I highly 
> recommend looking at this arrangement if you are unhappy with your 
> current reefing setup.
>
> Photos:
> Aft setup: https://www.dropbox.com/s/rwak1gxic3o9i1f/DSC_0015.JPG
> Aft closeup: https://www.dropbox.com/s/akrgxjytcokwbya/DSC_0017.JPG
> Aft reefed: https://www.dropbox.com/s/4gre3yxqilt1zgd/DSC_0020.JPG
> Forward lower: https://www.dropbox.com/s/tpfb40a0g9zy7a5/DSC_0018.JPG
> Forward upper: https://www.dropbox.com/s/rm4h0rzdaafauxi/DSC_0019.JPG
> Forward reefed: https://www.dropbox.com/s/gep5yk51fcmkasc/DSC_0021.JPG
>
>