Sunday, June 30, 2019

New Rig #1 Starting From the Bridle

While the boat was on the hard over Winter, I took the first steps towards building a new rig, starting from the ground up as it were, with the forestay bridle and bridle u-bolts.



Bridle and u-bolt positions

My original bridle was 5/32 1x19 stainless steel wire with 1/4" u-bolts. They were still tight after 10 years, but there was polish and wear on the u-bolts where they take the load from the bridle wires. The plans say that the bridle wires should be 3/16, so they were undersized as built.

There has been much discussion on several internet forums about building reliable bridle anchors. Later Wharram designs were specified with cord lashings instead of u-bolts. However, I was reluctant to drill multiple holes through the stem and wanted to keep the u-bolts. In an internet posting Rory McDougall had recommended 5/16 "or even larger" u-bolts to be on the safe side. 


3/8 u-bolt bearing surface and 1/4 stainless wire

Word to the wise - use forged u-bolts. Wichard makes a range of them and even the 1/4 Wichard u-bolts are rated to 1400 lbs working load and 4,400 lbs breaking load (that is, around a 4X safety factor breaking to working load). Unfortunately, I was on the hard at the boatyard and could not wait for the 2-week delivery time for Wichard bolts. So I bought some West Marine 5/16 316 (non-forged) stainless bolts - big mistake. These were "rated" to "2,200 lbs working load" which is a strange number because the breaking strength of a rolled stainless 5/16 bolt is about 4,000 lbs, and working load is some multiple of breaking strength (2X, 3X, 4X etc.). So 2,200 lbs is not even a 2X safety factor from the breaking strength of the bolt. Further when I was installing these bolts, I torqued them to the rated 11 foot pounds for a 5/16 bolt and they galled (welded in place). This happened to both bolts, so I bought a third bolt thinking that I had over tightened them, and carefully torqued this third bolt, and it to galled before reaching the final torque of 11 foot pounds. Thanks West Marine! Most of the stuff I buy from WM seems good quality, but these u-bolts were so bad that they are dangerous.


5/16 threads and nylock nuts on shaped base

So, then I found these stepped Ronstan u-bolts that have a 5/16 thread and a 3/8 U section. This gives me a working load for the threaded bolts of around 1,000 lbs (based on the 4,000 lb breaking load of a stainless 5/16 bolt), and the much larger section of the stepped U to absorb the wear of the bridle. Note that with each u-bolt taking the load on two threaded ends, the true working load is going to be much higher than for a single bolt. Unlike the awful WM bolts, the Ronstan bolts could be torqued and un-torqued to the 11 foot pound rating with no problems whatsoever (that is, good quality steel).

OK, so I had my u-bolts.I then spent considerable time drilling the mounting points oversize, filling them with thickened epoxy and then re-drilling them to the correct clearance size so that the u-bolts could be torqued into place and then removed whenever I want to, rather then being glued into place as the previous ones were. I also made aluminum mounting wedge plates that allowed the u-bolts to mount fair and square from the stems (rather then pointing forward because of the angle of the hulls) and epoxied them in place.


Rated triangle link ready to go

The next decision was which wire to use for the bridle. The plans specify 5/32 6x7 stainless wire for the standing rigging and 3/16 for the bridle. That wire (6x7) is generally no longer available, so I used 7x7 which is ideal for self-made rigging as it is flexible enough to use Nicopress swages. Working load for 5/32 7x7 316 wire is 440 lbs and breaking load is 2,200 lbs (see image below which belongs to Suncor USA). This specification from Wharram is obviously usually fine because there are hundreds of Tiki 21s sailing around the world with standard spec standing rigging. However what are the actual loads that a Tiki 21 rig is exposed to? It turns out that there is no easy formula for this important question and expert sources invariably say that there are too many variables to easily quantify. One source is a small table in Brian Toss's Rigging Guide that suggests that loads on a 20 foot boat are around 500 lbs, which fits with the Wharram's original spec.

But what about peak loads? I had a Harken High Load (wire) Bullet Block deform and almost break on the mainsheet bridle (which takes the full rig load). I assume that this was with the rig powered up going to windward in the usual 20 knot summer breezes in San Francisco Bay. That block is rated at 500 lbs working load and 2,000 lbs breaking load. This unscientific study leads me to believe that rig shock loads can approach the breaking strain of the standard spec 5/32 wire or, at the very least, that the rig is exposed to loads way beyond the working load safety factor. So what to do? For my new standing rigging I am going up one size to 3/16 wire which rates at 620 lbs working load, and a hefty 3,100 lbs breaking load - well beyond the shock load that nearly broke my Harken block.



All well an good, but what about the loads on my new bridle? The reason why the standard spec for the bridle wires is larger than for the rest of the standing rigging, is that the angle from the forestay to the bridle wires subjects them to a higher load. The graphic below (from LifTechniques.com) shows that lifting slings need to be rated to match the loads of the angle of the sling. The Tiki 21 bridle angle is about 60 degrees from the vertical, and the chart below shows that this doubles the load on each sling (each arm of the bridle). This means we need a wire rating 2X what it is for the rest of our standing rigging, or, around a 1,200 lb working load.


Going back to the table from Suncor, the next size up is 1/4 wire with a working load of 1,040 lbs and a breaking load of 5,200 lbs. This doesn't quite make the 1,200 lb level but is a full size larger than that specified in the plans, and if the rig does endure shock loads approaching 2,000 lbs, that will be 4,000 lbs at the bridle which is still well below the breaking strain of the 1/4 wire. Also, the 1/4 wire is really hefty, and going to a larger size would look plain ridiculous and would require huge swage fittings.

So that is what I went with, and the bridle was assembled from 1/4 316 stainless 7x7 wire, using a hand Nicopress tool and stainless fittings. The 1/4 size was maximum for the hand press but was quite doable after a bit of practice.

That just left the fitting to join the bridle to the forestay. The Wharram spec is an oblong quick link fitting, but it always bothered me that the oblong shape left the bridle wires at an odd-looking angle. So I sourced the Maillon Rapide 3/8 316 Stainless Steel triangle delta link that you can see in the above picture. It took me a while to find and order this part, and I went to the trouble because it was the only brand that was available in 316 and that had a test rating.

The bridle is now finished and installed, and is now just waiting for me to finish the new mast and the rest of the rigging - more on that later.

Tuesday, May 21, 2019

New Portlights (windows)

What do you call a window on a boat? Porthole? I think of a porthole as an opening window, so not that. In our family we always called them portlights, so that is what I'm going to go with - new portlights.


New 3/16 tinted acrylic (still with the sticky paper on) over the old faded and crazed portlights


During the last haul out, I took on the faded and scratched portlights that had done a good job for 10 years. The original builder had committed the crime of sealing the portlights with silicon. It took a day of solid work to get the silicon off the cabin sides for four small windows. I knew it would be a tough job and was convinced by the interwebs to order and try an expensive product called Debond Marine Formula. I can't honestly say that it did anything. In the end the most effective method was a good ol' razor blade followed by sandpaper. You can never get silicon entirely off, but I got the hull sides dead smooth and clean, if still a little slippery. I then went ahead and prepped and painted the cabin sides with 5 coats.


Pre-applying the butyl tape and screws

I ordered new 3/16 tinted sheet acrylic, and cut out the new windows using the old ones as templates. This made the whole job really easy and starting from scratch without the templates would have been a much bigger job. I clamped the new acrylic windows to the old ones and drilled through the old screw holes to get perfect reproductions of the original portlights.


Leave the protective film on until the portlight is installed on the boat

Instead of using a permanent hi-tech bonding goop, I used an old fashioned product that has come back into vogue - butyl tape. This stuff is amazing - it has the consistency of plasticine and can be shaped to suit what ever you need to seal, in this case a bead around every window.


Back in place

I pre-applied the butyl tape in a bead around each portlight, and stuck each of the screws through the tape ready to re-fit on the boat. It is best to leave the protective film on the acrylic as long as possible to protect it during fitting.


Looking swish

Back on the boat, the fitting was very easy, with the screw holes lining up perfectly. I reused all of the original screws, but bought new nylock nuts and washers. As you tighten down the screws, the butyl tape squishes out and you can stop at the point that you are happy with the seal. The excess can be scraped off with little residue left behind. The best thing is that the butyl never goes hard, and the next time the portlights need to be replaced, they will pop right off. Now I just need to convince one the Little Helpers to come and hold the allen key outside while a do the final tighten down on 60 nuts inside the boat.

Sunday, May 19, 2019

Painting Time Again

I clearly haven't been posting much over the last few years as, looking back, it all seems to be about haul-outs and painting. In reality, it has been every 2 - 3  years which coincides with the life of the Brightsides top coat on the hulls.

So, out the boat came over Xmas and it was time again. The two coats of Brightsides from the last round were solid at the tops of the hulls, but were starting to pit all around the waterline; I guess that the constant wave action and floating debris have more affect than I would have thought.

Little Helper #2 sanding between coats (smiling or frowning?)

So, sanded the hulls down and filled the pits with Interlux Surfacing Putty. Spot primed with Interlux Prekote i.e all around the waterline. Sanded and more Prekote. Sanded and first coat of Brightsides. Sanded and second coat of Brightsides. Sanded and third coat of Brightsides (yes, managed three coats this time!). Then new numbers and name transfers.

Ready to go

But wait - that was just the easy stuff. Also removed the windows and got three coats of Brightsides on the cabin sides too (also replaced the lexan windows - more on that later). DONT EVER USE SILICON on windows or anything else!! It took a day's work just to scrape the silicon off those teeny tiny window edges.

I also pulled the center main beam, and refurbished the beam chocks. The chocks on the port side had small pockets of rot, so I cut them off and replaced them with solid G10 blocks - they will never give trouble again until the end of Creation (no pics - too busy). I then finished up with three coats of top coat (plus prep) under the beams.

Heading out. Good shot of the Trinidad bottom paint



I also removed all of the center decking, and found further cracks in the fillets of the center section (see, last haul out). So, I taped ALL of the fillets of the center section with 4" 10 oz glass tapes, and don't expect further issues (no pics, too busy). Also, found spots of soft, wet, wood in the rails along the cabin sides that support the decks. Dug those spots out and filled with thickened epoxy. Then all those projects had to be finished with two coats of primer, and three coats of top coat.

Still missing some decking

Last time I used Interlux Bottomkote Aqua for the bottom paint and it held up quite well over 2 and a half years. It had hard growth after one year, but it scraped off fairly easily. Being water based it was very easy to work with and paint on the boat, with easy wash up in water.

On the other hand, it did get heavy growth that needed cleaning off. The Wharram deep vee hull is very dependent on being clean to perform well, and I decided to bite-the-bullet this time and cough-up for the really expensive and super toxic Pettit Trinidad. I got it on special for $250, and put on two coats with extra on the edges. This stuff is toxic - it was impossible to be around without the vapor breathing mask and stunk out the car for weeks. It is supposed to last for two seasons, so I will let you know.

Ready to splash

I did other jobs too, but too much to describe here without getting boring. Just a note on ongoing maintenance - if I was a builder I would use G10 on all high-wear edges i.e. hatch sides, cockpit coamings, beam chocks, deck rails and net rails. These are the areas that have required repeated maintenance on Little Cat as they were made from unglassed plywood. If G10 were used in high wear parts of the boat, and it was painted in two-pack linear polyurethane, then one would have a relatively low maintenance boat.

Monday, December 31, 2018

Gunkholing the Marin Coastal Seashore

Many times I have driven the Highway One coastal road to Muir and Stinson Beaches, and enjoyed the views of the rugged rocky seashore and the big Pacific swells crashing into it.

 
This part of the coast is usually closed to exploration by Little Cat because of the rough onshore conditions driven by the prevailing North Westerly winds.

Heading out. Note the morning shadow.
Very occasionally and usually in Winter, a period of contrary Easterlies will calm this coast, giving a temporary opportunity for gunkholing.

Pt Bonita North. Still some smoke from the Camp Fire.


Such was this occasion in late Fall, although still not without issues as the Easterlies were blowing 20 knots with gusts to 30 knots, and the only shelter was close up against the shore.

Directly under the Muir Beach Punta Vista.

So ironic to find calm shelter where it is usually a cauldron of angry water. Had lunch in this spot (above), and for the second time on Little Cat, could not get the anchor up. On the previous occasion, I buoyed the anchor line and came back days later with my snorkeling gear. That was not an option here, as it might not be calm again for weeks or months, so gave it full power with the outboard until the anchor shaft bent and it came up. Totaled the anchor, but luckily I have two.

Looking South past Slide Ranch


After lunch, Little Cat and I, explored north past Slide Ranch and got a close up look at the dozens of rocks and largely never-seen little rocky beaches along the shore line.


Looking North to Gull Rock.

I had to pay close attention, as we were constantly buffeted by 25 knot gusts if we got too far away from the shore. Little Cat was doing 5 knots downwind with no sails up!


No escape from the 25 knot gusts off the shore.

We circled around Gull Rock to head back to catch the tide through the Gate. Gull Rock was alive with seabirds, and is in a grand setting overlooked by a rocky point rising 1,000 feet (bisected by HWY 1).


Gull Rock up close (with gulls).

Sailed back on the first reef for the main and jib, and tacked through the Golden Gate Channel. Under the bridge the wind had veered allowing a close reach behind Angel Island.

Close up of shoreline route.

We stopped at this great spot under Bluff Point (Tiburon) to take a break and tidy up on the way back. In so doing, I spilled a bottle of Boat Soap that went all over the deck, starboard cabin, and into the bilge. Expletives followed. Note to self: don't carry around bottles of spillables.


Friday, December 28, 2018

Boat camping

is what my daughter calls it. What could be better than combining the fun of camping with the joy of sailing?



The boat tent is a large rectangle of Sunbrella that lies across the gaff plus the boat hook to get enough length. It provides a large usable area, with shelter from the sun or rain.

Ship to shore in Little Cat Too

The tent makes overnighting much more comfortable, keeping the decks dry and allowing free movement between the hulls during the night. The old man sleeps on the deck in complete comfort, while the little helpers have a cabin each.

The Little Helpers beach combing at China Camp.

This particular trip started at China Camp on Angel Island. The Little Helpers like to escape in the dinghy and explore the foreshore. At dusk we were lucky to see a deer and her doe appear and forage along the beach.


Dinner was noodles and soup, followed by a great deal of longing around and enjoyment of the sunset.

 

The next morning, the Little Helpers took Little Cat Too east around Pt Simpton to explore the beautiful sheltered beaches there, and to jump off rocks (of course).
 
Pt Simpton behind.

It is really deep along the shore here, and almost always very sheltered. I spend a lot of time anchored 10 feet off this shore. It is so deep I am surprised that other cruisers don't pull in and anchor here, instead I usually have it to myself.


Little Helper #1

Little Helper #2


  
A few months later, we did another overnight at Quarry Beach (East side of Angel Island). This trip was much colder and breezier, so had the boat tent cinched down closer to the deck to give more shelter and less windage.


 At some point I will sew up a zip-on section for the bow end of the boat tent. This will stop wind and rain from blowing through entirely and then we will have true boat camping luxury afloat.
 

Sunday, May 13, 2018

Its the small things

Inexpensive indispensables (a living list):

Sea Foam $7

 

https://i5.walmartimages.com/asr/0e959f7f-d0ea-4543-9d72-e1e259f15298_1.e866b5e5740d1cba9647a62ff223ee6d.jpeg?odnHeight=450&odnWidth=450&odnBg=FFFFFF

Added to the gas tank keeps the outboard fuel system copacetic and saves $$ in maintenance. My recent outboard overhaul revealed a pristine carburettor after 125 hours of use.


Pee bottle $10

https://i5.walmartimages.com/asr/0074a769-3163-411f-bed1-705863878b30_1.b0125e0b4127ada4c8bc59ea7a816bea.jpeg?odnHeight=450&odnWidth=450&odnBg=FFFFFF
Nearly drowned several times trying to pee over the side in rough weather. Now I sit in comfort safe in the cockpit. Also, don't have to go up on a wet cold deck in the middle of the night to go for a pee.

Gorilla Grip (or similar work gloves) $5.50

https://images.homedepot-static.com/productImages/874c6289-56d6-438f-8552-90468e3a6f7e/svn/blacks-grease-monkey-gardening-gloves-25054-030-64_1000.jpg

Work as well as any fancy sailing gloves. Tough nitrile palm and fast drying nylonish back.

PVC work gloves $7


https://images.homedepot-static.com/productImages/dc7667c7-891b-48d5-bb4e-2bdf7f08183d/svn/blues-grease-monkey-gardening-gloves-23408-08-64_1000.jpg

They don't look stylish - the crew on "yachts" will look at you aghast, but these are as good or better than fancy "waterproof" sailing/helmsman's gloves that can cost big boat dollars. ALL OTHER gloves will get wet eventually. These are a bit clumsy, but you can tie knots with them on. They will get clammy after hours of use, but with a pair of the above Gorilla Grip or polypro gloves as liners, they will keep you hands dry and warm in the worst conditions.


Plastic basin $12

https://lh3.googleusercontent.com/proxy/_amdDW-9ViKXvNYnqzOnytShyPtSWUFAI-lnPkhYiwA8tlVySCGTaGH1TkETnroLa7lahLAeTqwvs_5K9NkJgfL1zmnoyEyBDcmDc2XOGc00akT8IjEMjBavnOuGp5QoEv3waIlMZd2gheop5uhafOKI_5OAtpRKOaQHp597Zc2Es1fZeg=s500-pd-e365-pc0xffffff

With one of these babies, you can do anything that you can do in a fancy galley: you can also wash the dishes and yourself when necessary.

Poop bags $12

https://i5.walmartimages.com/asr/a707d05c-1354-4c1a-94dc-f7b95115005e_1.2e3d50129e5f3c95954d30483030c11e.jpeg?odnWidth=undefined&odnHeight=undefined&odnBg=ffffff
Forget about fancy Heads, whether hand pump, electric, or composting. Don't even think about a sloshy portable toilet. These self-sealing bags are the creme de la creme of the camp toilet genre. All you need is a comfy bucket, and these bags self seal and can be disposed in the trash at your convenience. I believe that they are legal for disposal of human waste in California (but don't quote me).

Lanacote $13

https://www.backscatter.com/ITEM_IMAGES/ac-lc_1.jpg

Lanolin (sheep wool oil) anti-corrosion goop. Use it to assemble all hardware on the boat so it will come apart in the future, especially with stainless steel in aluminum fastenings. There are much more expensive products, but this stuff is so cheap you can have a tub of it on the boat and slap it on all of your projects. You can also use it for all electrical fittings to keep the water out. The only catch is that it is quite smelly (like sheep).

Thursday, April 5, 2018

The boat didn't notice

the beating from the confused sea state on the way out of San Francisco Bay, but my stomach was sure feeling it. We hit strong wind-over-tide conditions coming past Angel Island, and then ran into wind waves and sea swell clashing from different directions as we passed Pt Bonita on the way to Drakes Bay on our first coastal cruise for 2018. In a confused sea state, the ultralight Tiki bounces around like the proverbial, and things did not improve until we were well past Duxberry Pt (Bolinas).


The video below shows us encountering the start of the ocean swell as we pull away from Duxberry Reef. The swells are still bouncy from the wind waves, but things are starting to improve. We had a nice close reach/beat all of the way past Pt Reyes on a single tack in a steady 10 knot breeze.



Although this was my 4th trip to Drakes Bay in Little Cat, we had never rounded Pt Reyes itself. On this trip I decided to take a look around the corner in prep for a future trip to Bodega Bay and/or Tomales Bay, and so sailed the extra 5 NM to do so - what a spectacular setting for the Pt Reyes Lighthouse and how wonderful the views must be!

Leaving Pt Reyes astern

Then it was back to the calm shelter of Drakes Bay to put up our new Sunbrella deck tent and kick back with some food and a nip of bourbon after a good day's sail.

Looking East to the historic Chimney Rock Lifeboat Station (1927) at sunset

Snug under the deck tent, I had a big bacon, egg, tomato and onion cook-up, while the sun went down, then settled down to watch and listen as night settled in.


Looking West towards the old Pt Reyes fish docks

You can't have too many bacon and eggs, so after a redo in the morning it was time to pack up and move out. I only had to run the outboard for a minute to get us away from the shore, and then it was engine off and we ghosted out of the Bay wing and wing past the treacherous breakers beyond Chimney Rock - don't cut that corner, as I was tempted to on the way in (see video below)!


The breeze was a very light 5 knots from the West, so we hoisted the symmetric spinnaker to make the most of it. What followed was a great spin run all of the way back to the Shipping Channel, and then a series of gybes north until around Mile Rock.

Running home under spinnaker in the morning

The wind gradually built during the day until it reached around 15 knots, and gusting over 20 knots. The ocean swell continued to build until it reached the forecast 10+ feet as we crossed the top of the Four Fathom Bank into the Shipping Channel. There, to my surprise, we encountered the BAMA Double-handed Farallones fleet as they were running back to the Golden Gate under spinnaker. We got overtaken and passed by a succession of big, fast, boats including several F-31 trimarans.

By the time I dropped the spinnaker at Mile Rock, I was very tired after sheeting the spin for several hours in increasing winds. For the last hour or so, I had to pull the tack and sheets in tight to de-power the sail as the wind built. My little symmetric (240 square feet) is cut too flat to be stable dead down wind and requires a lot of trim.

We sailed the rest of the way home under the white sails. 90 nautical miles, this trip.

Update:

Sailing photographer Leslie Richter was out taking pics of the returning BAMA fleet and got some great shots of Little Cat coming down the shipping channel to the Golden Gate (below).

Farrier F-31 is bearing down on us at speed



Wing and wing


Homeward bound