Thursday, March 11, 2021

Fine day on Fourfathom Bank

The entrance to the Golden Gate Channel is guarded by an area of shallow water called The Fourfathom Bank. It is a sand/mud bank built up over millennia by the tidal outflow from The Bay and the rivers draining from the Sierra. The Bank is notorious because of the lumpy seas that it produces, even in mild conditions. When there is a big swell running, The Bank becomes a spectacle with 20 plus foot waves breaking for miles out to sea. Many sailors have come to grief on and around the Fourfathom Bank.



The depths in the middle of the bank are less than 30 feet even four and five miles offshore. A channel passes through the semicircle of shallow water guarding the Golden Gate allowing commercial shipping and the rest of us to pass through.



On a fine day in February, I headed out planning to meet my family at Bolinas. As often happens, I left a little late so abandoned the original plan and sailed an erratic path out and over the Fourfathom Bank. The wind was blowing barely 10 knots and the ocean swell was small. Nonetheless the waves over the bank were steeper and closer together than one would expect given the benign conditions (see video above). You can imagine what it is like out here when things are really pumping!

Did you see the porpoise? I have been trying to photograph a Harbor Porpoise for years, but their fast movements defy getting a good shot. By coincidence I caught a porpoise surfing behind the boat in the video - if you missed it see the edited version below (look at the top left of the video).

Friday, January 22, 2021

Overnight in Sonoma Creek

I often cross the Sonoma Creek bridge on Highway 37 on my way to work. It is a calm and beautiful setting and a high point of a long commute, and I have long wanted to make a visit.


The creek entrance is quite a long way from the North Bay, through San Pablo Strait and right across San Pablo Bay. We left late early in the evening and had a marvelous sail in the dark across San Pablo Bay. The wind was 10 knots on a close reach and the sea was mild with a following tide. 


Morning calm in Sonoma Creek

It is very shallow approaching the mouth of the Sonoma Creek and I slowed to take soundings with the lead line. We covered a mile or so with only a couple of feet under the keels.

It was difficult to see the boundaries of the creek in the dark, but we managed to work our way into the creek and drop the anchor. I put up the boat tent and settled in. I soon realized that it was a clear and very cold night and that I forgotten my sleeping bag. I got dressed up in all of my foul weather gear and wrapped myself in the mainsail in an attempt to keep warm. I woke in the early hours and was very cold, so gave up and lit the stove. I sat for quite some time over the stove before I was able to have another go at sleeping.

I got up early and took the dinghy for a row under the Highway 37 bridge. It was completely still and very beautiful. I rowed past the early morning fisherman and took a short turn up Napa Slough before returning to the creek. I went a little way up the Sonoma Creek before turning back.

The Creek approach and dingy trip under the bridge

Back at the boat, I had breakfast and then started to head back. It was a completely calm morning so had to motor all of the way. I wasn't ready to go home right yet, So pulled into the Marin Islands in late morning and settled in for a lazy afternoon.

Napa Slough

I expect to repeat this trip because the creek is a very sheltered anchorage and is a great destination on an incoming tide in the bay. The trip was 34 nautical miles return from the North Bay.

Sonoma Creek

Rowing back towards the boat and the Bay

Tuesday, December 1, 2020

Overnight in the Gulf of the Farallons

In mid-summer I spent an overnight drifting hove-to in The Gulf before spending a morning at the Farallon Islands.  Little Cat and I did not get a usable breeze until crossing out of the "Precautionary Area" on our way out from The Bay. We managed a gentle beat on a course that would take us just south of the Farallons. At dusk we hove-to a mile or so East of the islands and set the boat up for the night, putting up the "cockpit tent" (cover over the open port hatch), turning on the AIS, and cooking a simple meal.


The S-bend is hove-to during the night

Conditions were ideal with a foot or so of wave/swell action and winds 5-10 knots with gusts to 15 knots swinging around a NE direction. I learned something very important on this trip which is that Little Cat "hove-to" very well on the same (port) tack with just the jib a little over-sheeted, and the main sheet eased with the tiller tied down to starboard - that is, not truly hove-to in the traditional sense which would be with the jib pulled in to port on the other (starboard) tack position. The boat stayed "locked in" all night set up like this - the over-sheeted jib and slack main kept her pulling slowly to windward, but kept her from tacking to port regardless of what the wind did.


Approaching in the morning

I settled down in the port hull under the hatch canvas and tried to sleep between the half-hourly Channel 12 traffic reports. I had carefully chosen the area of water to drift in after long study of the traffic movements in The Gulf. The area between the Farallon Group and the Northern Shipping Channel sees very little traffic from commercial shipping because of the dangers to navigation represented by the islands. That doesn't mean there is no traffic, but less risk from being run down by a ship or tug. I did not sleep much, but when I did I was awoken by the Traffic Report every 30 minutes at which time I checked for AIS targets and had a good scan around. By early morning, Little Cat had fore-reached within two miles of the Northern Shipping Channel and we seemed too close to the few passing ships, so I moved the boat over to the starboard tack to reverse direction and stop us getting any closer (at the end of the S curve on the chart above). 

The Channel between East Landing and Seal Rock South of SE Farallon

Around 6 AM I got up and trimmed the sails for a close reach to SE Farallon. My plan had been to visit the Middle and North Farallons, but I had not got much sleep and didn't have the energy opting instead for a quiet breakfast stop at the SE Farallon.

We rounded the west end of the island and followed the coast across Mirounga Bay (South of the island), past the residence houses (biologists) towards Seal Rock. I dropped anchor beside the East Landing and what I believe is called "The Great Murra Cave" (from the only map I could find naming features on the island).

Lunch spot be the East Landing

This spot was alive with sea life. Groups of seals cavorted around the boat. A small whale breached continuously a hundred yards behind the boat and appeared to be playing (one of six whale sightings throughout this trip). The number of birds is indescribable - see videos below to get an idea. Excuse my usual lack of videography skills.

Anchored next to "The Great Murra Cave".

Rounding the east side of the island towards Fisherman's Bay

I brewed up some coffee and food and enjoyed the moment. I would like to come back to this spot and spend the night, though the holding did not feel good (rocky). We then headed back for the 25 NM stretch to the Golden Gate in flat calm conditions. I had to motor all of the way back though with some mainsail assist in very light air. The Tiller Pilot had stopped working on the way out - later revealed to be a broken fluxgate - so I was stuck on the tiller for hours and became reacquainted with the "tyranny of the tiller".

The bigger picture

Monday, November 16, 2020

New Rig #3 The Mast Base

The new mast is 4" by 1/8" T6061 aluminum as specified by the Wharrams. It is 25' in total length, as opposed to 21' in the plans, to give me a bit of clearance under the main for general comfort, and to allow me to fly a large spinnaker in light air. Aluminum tube comes in 20' lengths, so the completed mast is in two sections sleeved together.


This first picture shows the arrangement inside the mast base. A one inch aluminum tube is welded to 6 inches of mast section that has been cut to fit tightly inside the mast. Rather than weld it all together (which causes hard spots and other issues), the welded sleeve is riveted with 1/4" 316 rivets through the mast and additional 1/8" aluminum plates on the outside of the mast. So the 1/4" rivets are going through a total of 3/8" of aluminum on each side of the mast pivot.


This picture shows the mast mountings which were made with hand tools from 1/2" by 5" T6061 aluminum angle. They are bolted through the center beam with 3/8" 316 bolts. The mast pivot pin is made from a 1/2" 316 bolt and is secured with split pins. You can just see the nylon washers that are on the pin to stop the mast working against the mount. You can also see the outside plates supporting the pivot tube in the mast in this picture.


Here you can see the new mast base mounted. Note the rear of the mast bottom is cut away to allow the mast to rotate without hitting the beam and to give space for the mast wiring to exit.

Here the mast base is revealed as a short 5' section that will be sleeved to the rest of the mast after the base is installed. You don't often see a torque wrench on a Wharram.


The base fitting is all done and lifted up. The slots are for the yet-to-be fitted internal halyard roller fittings and the numerous holes are the pre-drilled mountings for the halyard horn cleats. Yes, it is a very robust set up, but is still light in weight.


Here is how it looks in action

Tuesday, November 10, 2020

Bolinas Lagoon Overnight

The Little Helpers and I decided to do an overnight in Bolinas Lagoon, after which I could drop them ashore the next day to surf with their Mom at Bolinas Beach. The lagoon was also on my "must visit" list so was glad to finally get on with it. On the sail out we encountered 25 - 30 knot gusts in The Bay and then very gentle conditions in open water (typical bipolar weather conditions here).


We encountered several pods of whales about a mile offshore as we approached Stinson beach. It was enough excitement to get the girls out of their cabins, but only just.

Crossing the Bolinas Bar was something I had spent some time preparing for. We had been visiting Bolinas Beach for many years giving me lots of time to observe the comings and goings across the bar at different parts of the tide. I also swam across the bar a month or so earlier to check the depths and channel location. As we approached the bar, I had the Little Helpers sit on each deck with their life jackets on just in case. The ocean swell was only one foot (on the face) but was still faster than the Tohatsu at full power, and we were overtaken by a breaking wave - no problem with the Wharram design but showing that we can only do this bar in ideal conditions for safety.

Inside the Bolinas Lagoon

Inside the lagoon seems large but is mostly shallow water at anything less than high tide. We tried several spots and anchored for the night next to Kent Island. The girls went for a walk into town and came back wet after crossing the channel to get back.

We settled in for the night with the tent up and had an early night after a feed.

Next morning was overcast but still beautiful.

The next morning the girl's Mom showed up on her surfboard, and we up anchored to drop the girls at the beach at the channel entrance. The sand shelves deeply and they stepped off the bow of Little Cat into ankle deep water. The girls stayed to surf for the day and then went home with Mom. I turned the boat back into the lagoon and followed the channel to go exploring.

Little Cat drying out in the middle of Bolinas Lagoon.

We got about half a mile before running aground on a sand bar with the tide dropping. The boat ended up high and dry and I spent the afternoon walking around the middle of the Lagoon on the hard sand.

A refuge for large numbers of pelicans.

The lagoon is a breathtakingly beautiful place. An unseasonably large number of pelicans were staying over (according to a local out for a walk) and I had the company of hundreds of pelicans along with other shallow water birds.

A view of the boat I don't get to see often. On the hard at low tide.

I settled in for a second night, glad to have the deck tent as the breeze was mild but cool. I was surprised to find that my new Fortress 4lb anchor had dragged a couple hundred yards during the night. It was not entirely the anchors fault as the tide moves fast in the lagoon (I would guess 4-5 knots) and the sand is hard packed. I think the fast moving water washed the hard sand away from around the anchor, and it "flew" before re-engaging. Still, it is a reminder that the Fortress is suited to the mud of the Bay, not so much to anything else.

Complete stillness.

The morning was magical! Cool and foggy, but entirely still. So easy on the mind - what an incredibly restful place. I cooked up a bacon and egg feast, and then started packing gear away for the trip back to the Bay.

Bacon and egg treat.

Heading out back over the bar and the one-foot swell was still there at about mid tide. We threaded through the surfers with bow pointed skywards over a couple of peaking breakers. A two foot swell is going to be absolute max for Little Cat crossing the Bolinas bar, regardless of how favorable the tide is. We had a nice sail home, and encountered strong winds again on re-entering the Bay.

Bolinas Lagoon is a stunner and I will be coming back.

Saturday, May 16, 2020

Repairing the Raymarine ST1000+ Tiller Pilot

Dismantled tiller pilot.

I have been using the ST1000 since June 2013 (around 7 years) and have logged around 3,700 nautical miles in that time, most of it on autopilot. I have tried to be easy on it by not expecting it to deal with heavy helm or crazy running conditions. The Tiki is also a very light boat, contributing to my expectation that the tiller pilot has had a relatively easy life.

Broken ram seal housing (Xyzzy: Sailing Anarchy).

Recently it became clear that there was a water ingress issue as the LED screen was cloudy, or cutting out, and was not clearing up after a drying period between sails.

I disassembled the tiller pilot (top picture) and found two issues: the ram seal housing was broken, and the rubber ring and gasket that cushion the ram at maximum and minimum travel had disintegrated. I repaired the housing before taking pics, so the pic above is from another on Sailing Anarchy. My housing was broken on both sides, not just one side as shown here.

Arrows show G/flex glued fillets.

To repair the housing, I assembled it on its steel carrier and glued it with thickened West Gflex epoxy. I don't consider this a permanent repair and expect that it will fail sooner or later. I think that the broken housing allowed water to get past the seal, explaining the fogging of the LED screen.

Reassembling with the repaired seal housing in place.

I brushed down the electrical control board with alcohol and a toothbrush and removed some obvious spots of corrosion. I then let it dry for several days under a lamp, and also to let the Gflex set good and hard.

Electrical board refitted.

The rest of the tiller pilot did not show any obvious signs of wear and tear. The gearbox cogs and belts seemed to be operating OK. I reassembled the pilot taking extra care to replace the case seal without pinching it. The case seal had aged and was too long (stretched?) to fit neatly in the grooves, so I put it into the freezer for an hour to shrink it, and that did the trick. See videos below for testing after reassembly. The pilot is fully functional again

Testing the switch functions.

Testing the fluxgate compass in "auto" mode.

Close up of drive belts in operation.

So here is the thing: the reason the seal housing was broken and that the rubber gasket stops were mincemeat is that Raymarine does not install ram travel cut-out switches in the ST1000 and 2000. So when the ram reaches the extent of it's travel it just mashes into each end of the tiller pilot assembly. The motor and gearing are stronger than the construction of the seal carrier housing and it bends the mounting plate and breaks the housing. To me this is incredible, but is common knowledge to longterm users of these products, and clearly Raymarine. I share the amazement of many folk online who have shared their experiences about the demise of their tiller pilots! It is even more surprising in that the engineering standard of the pilots seems high overall - I guess that the cost of adding ram travel limits to the design was just too much for them to remain profitable. Anyway, if you have an ST 1000 or 2000, DON'T LET IT RUN OUT TO MAXIMUM TRAVEL in either direction if you want it to last. However, it has worked flawlessly for 7 years and nearly 4 thousand miles, so maybe that is a return on the original investment?

Voila! Ready to go again.

I don't know how long my repair will last, but fingers crossed for 12 months or so to build up the boat budget for a new pilot. I have done lots of online research and found that the Simrad 22 and 32 pilots have a ram position sensor that stops the motor at full travel. This is probably where I'm headed for a replacement, but it is too pricey at the moment.
Update 10/2020
The pilot only worked for a couple more hours and then the fluxgate compass failed. I was on my way to the Farallons and had to hand steer for the remaining  50 NM on that trip. A new fluxgate was more than $100 on Ebay, so I bit the bullet and bought a new ST2000 (around $450). I wanted to try the Simrad 32, but the covid prices had climbed to the $700 - $800 mark, which was just too much.

Thursday, April 30, 2020

Great Spots: Bonita Cove

In the time of the Corona virus, I have been lucky to be able to sneak away and get some fresh air and sunshine - to "shelter in place" in a nice place, as it were.

Little Cat Too in the Golden Gate Channel (essential for gentle exploration and pictures of the Mothership).

Bonita Cove is the last rest stop before you head out into the Gulf of the Farallones, a place of refuge when it is inclement "outside", or a beautiful destination in of itself.

Bonita Cove, Golden Gate.

The prevailing winds on the coast here are NE, so Bonita Cove is usually a place of refuge. In winter, there are periodic blows from the South, but by and large you will find an anchorage in most conditions.

Marin Headlands behind.
On this day, the temperatures were Winterish but warm in the direct sun.

Pt Bonita (Lighthouse), Bonita Cove.

A great spot to take a row ashore at the old Life Boat Station, take some pics of a cute boat at anchor, or read a book.

Bonita Cove, zoom out.

Making way out to Pt Bonita, Golden Gate.