[C320-list] Reefing system project

[clburti at gmail.com]

Doug,

May I use this for a Mainsheet Article?



Sent from Windows Mail



From: Doug Treff
Sent: ‎Monday‎, ‎June‎ ‎24‎, ‎2013 ‎11‎:‎43‎ ‎PM
To: C320-List at Catalina320.com

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


-- 
Doug Treff
doug at treff.us