Monday, June 17, 2019

Painting a Sail

No comic book super heroes or advertising logos. Just the UV strip.

Our new-to-us laminate jib is starting to fail along the edge of the sun cover; the cover makes a stiff spot and the flexing is damaging. The cover was also too small and is itself, failing (UV Insignia cloth). If I tried to sew on a new cover the needles holes would destroy the sail, and it's too old to justify the expense and effort, really.

If the ONLY thing we want to due is block the sun, why not paint? For the past year I have had samples of many different paints, ranging from house paint to specialized sail paints on racks on the roof, weathering. Naturally enough, it is a writing project.

I did a few minor repairs first. Yes, the strip tapers; you need more width at the clew than the head.  Normally I hate mini-rollers, but a 4-inch foam roller is just the thing for painting a sail. Pretty easy.

FYI, the sheets under the sail are there to protect the sail from the asphalt more than to keep the paint off the driveway.

Another advantage of paint is that it is light. I don't care about the effect on set, but I do care about the extra weight flogging against the vulnerable leach fabric. None of the sailmakers recommend Sunbrella, for example, on laminate sails. for this reason.

  Although the roof top exposure tests are not complete, I selected MDR's Inflatable Boat Topcoating. It seemed to be among the top performers, I've used it on inflatables, it got a top rating from Practical Sailor some years ago, and I had enough left over. Free is always nice.

No, I don't expect it to last as long as a Sunbrella cover. Neither will the rest of the sail. But it also cost me only 15 minutes work and $15 worth of leftover paint.

Look for a detailed report and follow-up in Practical Sailor Magazine.

Saturday, June 1, 2019

Cruising Small, Cruising Fast

A New addition to the Bookstore

I started started sailing on a beach catamaran. I heartily recommend learning on a small boat, because they teach a sense of the wind and waves that is hard to gain on larger boats. But if you want to go farther or spend the night, you really need something with a bunk. But you don't need 50 feet of shiny fiberglass and the mortgage and slip fees that go with it. That's what they sell in the mags because that's where the (your) money is.



And to be honest, big boats aren't that much fun to sail, not after you get the hang of it. They're more about learning the systems and planning than actually sailing. Would you you rather go for a bike ride or drive a Winnebago around town? Personally, I'd take the bike, and that is why I downsized from a cruising cat to a 24-foot trimaran; the smaller boat sails better and I feel the wind again. I missed that on the cruising cat.



The thought that brought fire to my pen is that too many sailors feel that sporty boats are for racing. Poppycock. They are for whatever is fun, and if you only take the plunge, you'll see that fast cruising is a blast, though it can be a bit more like camping that staying in a hotel. Of course you can do both; sail fast from point A to point B, and then stay in a motel.

And that is the sort of thinking that goes into cruising fast and small. Ignore the magazines and make it work. You've never had so much fun!


Friday, May 31, 2019

Shroud Tensioner

This probably won't interest most readers, but a fellow F-24 owner wanted some images.

Because the F-24 folds, a quick release of cap shroud tension is required. Pulling the shrouds aft with a tackle is a simple way. This can either be a cascade:


or a straight tackle:


A cascade places only 1/2 the load on the blocks and can thus be built using lighter gear. This is commonly done with vangs, for example, which also have a small range of travel. The only advantage of a straight tackle is that it can be adjusted through a greater range.

The PO (previous owner) probably used the blocks in a 4:1 tackle. I'm not sure why he went to a cascade, but it works very well. I assume he went to 2:1 on the blocks to avoid over tensioning, but I may go to 4:1 (the pulleys are there ) to make it easier to adjust under load, simply remembering not to yard on it.

Tuesday, May 28, 2019

The Best Rope-to Chain Splice

The Irony Spice



Joining chain to rope in a manner that allows it to feed smoothly has always been something of a challenge. Back in the day of weak chain and hemp rope, a 2-strand splice was developed to allow bulky rope to fit through a link. One strand was unlaid way back and the remaining strands go through the link in opposite directions, laying flat and sharing the load evenly. Even with the loss in strength around the link, 4 strands were as strong as the 3 strands of the rope. One of the strands would be laid back in the empty groove and terminated in the manner of a long splice, and the other back tucked like a 3-strand eye splice.

Feeds through a windlass like silk

Then ropes got smaller and stronger, and a simple 3-strand back splice or crown splice became the standard. The smaller line was as strong as BBB chain. Then we introduced G43 and G70 high tensile chain. By the time we use a rope as strong as the chain, the splice was too big for the windlass gypsy, and so the irony is we find ourselves returning to 19th century splicing technology.

It is a little more difficult to get the strains even, and the spice takes a few minutes longer, but you gonna love the way your windlass feeds. No more jams!

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The name "irony splice" was coined by Brian Toss, and this method is well described in his highly-recommended book, The Rigger's Apprentice. It takes considerable practice to get the tension just right, but if you have any ability with splices, by the third or fourth try you should be in good shape.

The following instructions are for half-inch three strand rope. For larger diameters, increase the spacings proportionately.

The Irony Splice--Instructions


  • Place a light seizing around the rope about 5 feet from the end.
  • Tape each strand separately and securely.
  • Unlay one strand back to the seizing, without disturbing the other two strands.
  • Place a light seizing across the two remaining strands about 3 feet from the end.
  • Untwist the two strands and lead them through the last link of chain in opposite directions.

  • Take one of the strands and lay it into the space left vacant by the first strand that was unlaid. Be careful to maintain twist in that strand, and to choose the strand most naturally lies in that vacant space.
  • When this strand meets the first seizing and the first strand that was unlaid, join the two strands in the manner of a long splice. This will require a locking overhand knot, back tucking both strands, and tapering.
Line re-layed, tying the overhand to start the long splice join.

 Long splice finished (not trimmed), ready to do the tuck-backs at the chain end.
  • Take the remaining loose strand, still hanging loose at the last link of chain, and tuck it back at least eight times in the manner of a back splice. Taper carefully.
 Much smaller in diameter, more flexible, and much easier to feed than the common backsplice. They got prettier with practice, but this one tested at 85% line strength. I eventually reached near 100%.


Thursday, May 16, 2019

Backing Plate Testing

Breaking stuff in the name of science is always fun! Parts of this appeared in Practical Sailor in 2015, some not.


The test rig

The bolt is tightened and torque recorded until something gives.
  

I tested laminate samples to make sure the failures were appropriate (good bonding). As you can see, the core is failing in shear.1 layer 17-ounce biax on the bottom, one layer 17-ounce biax and one layer 6-ounce cloth on the top, 1/2-inch end grain balsa.

I replaced core with plugs--standard practice.

The Poor

Starboard showed micro cracks after 3 week. It also creeps a lot--I had to keep re-torquing for 48 hours.
Teak is a big failure. Note how the distorted washer became a wedge.


 The Best


Just 2 layers of 17 ounce biax were very impressive, holding 1.5 tons. 4 layers would be correct for 1/4-inch bolts.

1/8-inch FRP bonded  did better than 1/8 SS, particularly on rough surfaces. 1/4-inch FRP would be correct for 1/4-inch bolts.


 The Bottom Line
  • 1/8" aluminum for light duty in dry locations. Thickness = 1/3 bolt diameter minimum.
  • 1/4" FRP most places, bonded if there is high load. Thickness = 2/3 bolt diameter minimum.
  • 4 layers of 17 ounce biaxial cloth for every 1/4-inch of bolt diameter, where there is high load and irregular surfaces.
  • Diameter of plate = 5 bolt diameters minimum.
And never, ever use fender washers. They bend into cones and are LESS effective than standard bolting washers in actually distributing the load.  Buy extra thick (Bolt Depot).
 A little more if the skins are very thin. Less with solid glass.



Monday, April 15, 2019

In praise of WAG Bags

On my last boat I had a conventional holding tanks system, and properly maintained and designed, I believe it is the best answer for most cruisers. I've done lots of research, used composting heads, and have no reservations about this recomendation. But with my new boat, the right answer is WAG bags.

WAG (Waste Alleviation and Gel) bags are widely used by the military and FEMA in situations where conventional sanitation practices aren't practical. For example, I used antifreeze in the toilet of my PDQ in the winter, and that worked well, but carrying a portable toilet on an icy dock from my F-24 seemed pointlessly dangerous. So I investigated WAG bags as a winter alternative.


A heavy duty bag and a gel very similar to that used in diapers. Pretty simple. We have a portable toilet, but we don't put solution in it anymore. These are simpler.


Not pleasant, to our western sensibilities. But think of the plus sides:
  • Light.
  • No head to clean.
  • No odor once off the boat. 
  • No pump-out station, no lugging the portable head home to clean and refill.
I'm not saying they are for everyone. We hardly ever use the head on the boat. We hit the shore side toilets before heading out, and if we drink some beer, that goes over the side. I doubt we use more than one bag a year.

But even when cruising, I would have kept a box onboard for emergencies, had I known of them. They can be laid right in the head (drain and clean first, obviously) or used over a bucket, no mess.


Not pretty, but darn functional.

Friday, April 12, 2019

Why Not Webbing?

As I did more with low friction rings, it became evident that rope is not the best material for sliding. Double braid can get lumpy and is high friction. Single braids, like Amsteel flatten under load, leading us to the obvious conclusion that webbing is better for some things. 

By including loops at several points, it can adjust to various reefing heights. This boat uses roller reefing, so there is no jiffy-reefing tack line.


For example, webbing has been used for years in dinghy Cunninghams. The purchase is doubled by running it through the Cunningham eye, but it's just a regular grommet. Webbing runs more smoothly, with less friction.

Webbing is perhaps the most traditional method of attaching sail slugs to the mainsail. Wrap 2-3 times and sew.

So what about other applications?

  • Lifeline lashings.
  • Sewn to the jib or reacher sheets at the end, there is nothing to hang up on.
  • Slab reefing outhaul tackles. Less friction through the clew ring.
  • Furler line. I use webbing on the reacher--I can fit more on the drum that way. The webbing is spliced to a larger rope tail.
  • Control lines that are underfoot on deck.
This is also similar to what we do when we strip cores, such as on furlers. I'm aware of that. You don't want to handle it under load and it does not play well with winches.

Ideas?

Wednesday, April 10, 2019

PDQ 32 and 36 Rudder Core

Posted just in case any PDQ owners were curious about what lies inside.


Tuesday, April 2, 2019

Anchor Lights Get Smaller

Once upon a time anchor lights took a huge bite out of your battery overnight. Some drew as much as 25 watts, costing you as much as 20 aH by morning, or nearly the entire usable capacity of a group 24 battery. The also burned out every 1000-2000 hours, requiring frequent trips up the mast to keep them burning. LEDs promised as much as 100 times less draw and lamp life up to 50,000 hours, but the the first generation didn't always deliver.


 On the left, the home-built masterpiece a PO installed. The engineering was pretty, but heavy and ultimately failed. On the right, the replacement Tecniq M10. It is tiny, draws less power, is USCG certified, and weighs less than 1/2 ounce. (both are 2.5-inch in diameter, both light through the same vertical angle)

They came from a cottage industry, some nearly works of art and others crude affairs. Some nav lights were the wrong colors. They didn't always shine through the correct angle. Some interfered with VHF, a particular problem with anchor lights, being located right next to the antenna. None were USCG approved.


I don't mind the heights, but the up and down trips for the stuff you forgot are annoying. In this case, I needed two odd size screws from the hardware store. I remembered everything else.

I'm keeping the old one on my bookshelf, like a little lighthouse. But I'm happier the Tecniq is at the masthead.

Saturday, March 9, 2019

Riding Sails

Some boats hunt all over the place in a breeze. Yawing through 90 degrees can double the force on the anchor and quadruple the forces working to twist it out. First, there are solutions related to the anchor and rode:
  • All chain. Helps right up until the chain lifts off the bottom.
  • Hammer lock mooring. A second anchor, just touching the bottom. Very effective in moderate wind, but can fail if strong enough.
  • Two anchors. A whole nuther' topic, but can work very well. Also complicated, particularly if there are other boats anchored nearby (you will swing differently).
  • Drogue on the chain. Didn't do much for me. You've got to be yawing fast for it to matter.
You can change your windage. After all, that is the source of the problem. Anything forward is like a riding sail at the wrong end.
  • Take the dinghy off the bow. Big difference.
  • Lower you reacher. Big difference.
  • Add a  riding sail aft. We'll come back to this.
And you can change your under water profile.
  • Lift the rudder. A HUGE help. But most people can't do this.
 I've been playing with riding sails. Single luff sails function by pushing the stern to one side, which creates a crude V. The problem is, it is very sensitive to how the boats windage changes with aspect change. Some it works, most not so much:
  • Push the boom to one side. Didn't do much for me. Yawed through the same angle, just to one side.
  • Riding sail. Same problem, plus it flaps when it reaches the extreme travel. Annoying.
I've also tried V-riding sails, with two luffs:

  • This is a Fin-Delta, from Banner Bay Marine. I've heard goo things and need to get my hands on one.

  • A less conventional approach is the V-Delta, conceived by Paratech but not marketed. Even this crude tarp was stable up to 25 knots. The grommets were set in a corner reinforced with only duct tape, and yet they didn't pull. The force is just not that great. It also reduce the yawing more than half, and the higher you set it, the better it works.

If  I didn't have  bridle, I'd be sewing one of these right now. So simple. Yes, it does increase the rode tension a few percent, but this is FAR less than the wind hitting the boat from the side and swinging it about.

Please share your riding sail experiences. I need to figure out what to test!