[C320-list] Reefing system project
Doug Treff
doug at treff.us
Mon Jun 24 20:43:59 PDT 2013
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
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