Friday, April 20, 2012

She's Mine!

When I decided to buy my PDQ 32 a bit over 3 years ago, the markets--boats, securities, and real estate-- were in the toilet. Boat shopping was good, but investments were down; it was a time to buy or hold securities, not sell (that should have been done earlier). So I borrowed the money for very little.

The deal was that I would pay the loan primarily with bonuses, writing income, proceeds from the sale of my Stiletto, and rent from a small commercial property I bought before I got married. I've been spreading maintenance dollars thin, mostly because I like to tinker and because of habit; it offends my pride if I can't fix something and perhaps design something better. I've got a cheap slip; $100/month.

And so in 39 months I'm all done. Feels nice being debt free, with only pluses on the balance sheet. Oh, she's going to need some money in a few years. The engines are long in the tooth and loud, but they'll hang a few more seasons. The main has a stretched leach, but it only shows in strong wind and I'm no racer. The tramp has only a few more seasons in her. But really, PDQs are pretty low-maintenance solid boats, so I'm looking forward to some pretty low cost relaxation for a while.

Ahhh.......

Monday, April 2, 2012

Google

I browse many forums and comment more than I need to. I tell myself that, indirectly, it sells my book. There's some truth in that. Mostly, I'm bored. And I do learn a lot; there are a lot of smart folks out there.

Yet I never fail to be amazed by the number of folks that ask dumb and overly broad questions  rather than make some effort minimal search the question first. I don't think I'm being to harsh. There are good questions: those on new topics, fine points, brand-specific problems or ideas, and those written just for the joust. But honestly....Search engines are the best free tool of our time. I feel bad, asking folks to type about something I could have found quickly, and I feel bad about wasting forum's space. And yet, dumb questions get the most answers, since the multitudes--including those that don't actually know--will post an answer. I find "ASK" to be hysterical; the clueless voting for right answers on topics they don't understand.

Pass the popcorn. My rant for the day. I've been waiting for a year for a reason to post this cool graphic.

Saturday, March 31, 2012

Bolt Hangers--A Strong Point For Small Dollars

Cheap hardware via cross pollination from the rock climbing world. In the mountains these are used in combination with wedge bolts to create strong anchor points. On a boat...
  • 5,000-pound strength anywhere a single 3/8-inch bolt is handy. Of course, a good backing is required.
  • 316 stainless steel.
  • Cheap. About $3.95. (others brands may be 304 or other grades, some of which have been known to fail in marine environments.)
  • Designed for clipping carabiners, they easily accommodate 2 carabiners.  
  • Obvious purpose avoids confusion over acceptable strong points. Strength rating and certifications are stamped on hanger.




Countless potential uses. A few of mine....
  • Add an extra block to a sail track.
  • Add an anchor point at the stern for diverting mooring lines or attaching a dingy.
  • Tether and jackline anchors. Don't tie rope or webbing directly; the radius is too short for acceptable strength.
  • Anchors to secure bicycles.

Handles

rev. 4-22-2012

Every boat has one line that requires a hard pull over a short distance. On the PDQ 32, it is the engine lift ropes, port and starboard. Every time you are finished with the engines they must be lifted: under sail the lower unit drag costs 0.4 knots and a gurgling noise, at the dock or at anchor, corrosion and fouling.

A tubing or pipe handle helps. Aluminum or stainless are best. Round the inside and outside of the cut.


Revision: the above photo shows and attempt with a bit of thin wall PVC tubing. It failed after a few weeks of use. Perhaps SCH 40 PVC would work--I think so--but I replaced them using some stainless tubing of the same diameter I had lying about; they will now last the life of the boat. On previous boats I had used aluminum tubing, which worked fine too.

Friday, March 30, 2012

The Case for Softer Tethers

Rev.1-2-2014
(Since the original post we have moved to dynamic rope tethers (softer catch), but I have left this as there is still good information and it is still valid. However, in reviewing a number of accidents, where multiple impacts would have been poorly served by a single use energy absorber, I now recommend dynamic materials [elastic, like climbing rope].)

As an experiment, hang in your safety harness for 1 minute. Go on. We'll wait for you.
_______________

Hurt pretty good after a few minutes, didn't it? Imagine falling a few feet on a 6-foot tether with no real shock absorption. The impact would over 10 Gs, or over 10 times what you  experienced just hanging there. The maximum, in lab testing, is over 20 Gs. Can you feel you ribs cracking and spine shattering? Of course, this is an exaggeration of anything likely to happen on a boat. How far can you fall?

Over the railing, of course. But there will also be some attenuation as the lifeline stretches and stanchions bend. The length of the fall will be lengthened about 2 feet (1 foot of give). YOu probably didn't really fall 6 feet; the jackline is inboard and if you fall more than 5 feet you'll hit water, depending on whether you went head or feet first. It.s going to hurt, but the actuall fall distance is only 4 feet and the was ~ 2 feet of breaking. The harness impact should be perhaps 3 Gs. Survivable with bruising, and probably no the worst case scenario.

Thrown from the cockpit. There have been a few cases where a sailor was washed out of the cockpit, the tether broke, and the sailor lost. How could the impact force have reached 4000-5000 pounds? Lets assume the sailor was thrown at 19 feet per second-- 11 knots, a good wave strike, only a fast jogging pace. He is clipped to a hard point--no give-- so the only attenuation will be the tether stretch, plus the wave is still pushing. In the case of the above 6-foot fall the time is about 0.61 seconds and the final velocity is 19 ft/second. Ouch.

It will save me a lot of typing if you visit this post about fall energy first. The long and the short of it is that falls on jacklines are less severe because the jackline stretches and the sailor also slides along during the line. Falls against a fixed anchor point are brutal. This is where we take up the thread.


_______________

I've made some effort to research sailing chest harnesses and injuries, with very little luck. Clearly, if a sailor takes a 4,000 to 5,000-pound hit in the ribs there will be serious injuries; OSHA and military studies support this. Yet, because of the circumstances of these accidents, the actual injuries are usually unknown. The sailor is lost. Other times there are injuries, but the assumption--right or wrong--is that the sailor hit something, other than the end of his leash.

The harness or tether is typically blamed, though there are 2 falsies in this logic: the harness should never have seen a 5,000-pound load because there should have been shock absorption in the system; the sailor would have very likely died from his injuries anyway.
  • "A lesson in harness and tether construction can be learned from Tami Ashcraft, who along with a sailor friend was making a sailboat delivery to Hawaii when they ran into a powerful storm. Ashcraft was knocked unconscious. When she came to more than 24 hours later, she climbed to the cockpit where a single tether dangled over the side. The D-ring had snapped where it was connected to her friend's PFD. He was gone. Ashcraft was convinced a round ring might have held, like those on Mustang vests." Ashcroft, in my opinion, was wrong in her conclusions.
  • 1998 Sydney-Hobart Race Accident. Glyn Charles was never found, after his tether parted. But the force of dragging his body through the water could not have generated that kind of force, only a sudden impact. The inquest stated that he was attached to a "fixed point" and thus would not have benefited from jack line shock absorption. The lanyard may have also been defective, though I can't locate the testing information. http://www.parliament.nsw.gov.au/Prod/parlment/hansart.nsf/V3Key/LA20010307027.  http://www.telegraph.co.uk/sport/othersports/snooker/2994528/Yachting-Charles-died-after-safety-harness-failed.html.
(I now believe dynamic tethers make more sense, in terms of energy absorption and multiple impacts. It seems that several or even most of the fatal MOBs that were related to tether failure involved multiple high impacts, and this need would be poorly served by a single use devise such as a Screamer. I have left this article as food for thought, but please refer to this more resent post for more up-to-date information.)


And this leads to a very interesting conclusion: the shock absorption device (Screamer) doesn't really need to be on the the tether, it could be on the u-bolt. It is the fixed-point anchor that is the hazard. If the sailor is on the jackline, the system will stretch and slide and nothing will break. Some sailors have expressed concern about the elongation of the Screamer on-deck, and this removes that concern. No one wants more clutter on the tether. Up front, the real hazard is being dragged in the water, as many have said. Only if the sailor is attached to a u-bolt in the cockpit is the impact force extreme! Thus, if we clip Screamers only to the cockpit u-bolts, the force is absorbed where it needs to be and no new hardware needs to be invented! While this adds a little cockpit clutter, it could save lives very cheaply. In fact, the mere presence of shock absorbers on construction lanyards has been credited with safer work practices, as it reminds the workers of the incredible forces involved. The presence of Screamers in the cockpit might even encourage sailors to shorten their tethers.

Well, at least that's one possible answer, something very simple that would only need be deployed in extreme conditions. This is much how climbers originally use Screamers; other applications came later. 

________________

So I made up some new tethers a few weeks ago, for my own use on a catamaran. These are my best yet, and I like them both, though for reasons I will explain below--multihull reasons--I like the one on the left better. They both have features I like, though they will not be for everyone. (I have since switched to dynamic tethers.)



  • Knots instead of sewn loops. I'm still playing with the lengths and years of climbing experience tell us that the knots are not a real risk. But years of climbing, industrial and marine experience also tell us that sewn joints are stronger, reliable, and durable. They would be sewn if I were not still experimenting. (These knots weaken the webbing about 30%). Tails must be 3 inches and knots must be tightened by bouncing on them with body weight to prevent loosening or slippage--standard climbing practice.)
  • Attaching the snap to the center of a 2-leg tether with a larks head is quite convenient. It is a simple matter to adjust the legs without re-sewing or re-tying the ends. The larks head will not slip appreciably during a fall and could also be secured with a lashing, though that is not needed. This also simplifies the construction if sewn and probably results in very little net loss over time; several fewer joins, it can be moved if worn, and there is no UV vulnerable stitching. It also takes the load equally well from either leg or from end-to-end.
  • We like screw gate biners on the jackline because we do not often unhook from the jacklines. They are light and snag-free. We unhook from the harness end. This is because we have a deep center cockpit and never harness in the cockpit. If you clip on-and-off the jackline, the Kong Tango is a better choice.
  •  Rope jacklines. Rope is stronger and withstands UV better than webbing. It offers controlled stretch, absorbing fall energy. It gives a better hand grip and clips more easily. On the down side, it can be mistaken for running rigging; on our boat this is no problem because of location and because we leave the jackline end attached. It is worse underfoot, rolling and making for poor footing; ours are not under foot because they are run on the cabin roof--cats are wide. If I had a monohull I would still strive to get the jacklines up against the cabin trunck and out from under foot. I might be forced to use webbing, which I would replace frequently (6-months?) and not like. I believe jacklines and harnesses are for everyday use, that practice with equipment breeds competence, and that rigging jacklines only when "needed" is a big mistake. Even more than reefing too late, who wants to be rigging jacklines too late, in a thunderstorm or at dusk? On a narrower boat, non-stretch rope is required.
  • Quick release on harness end. We don't, since getting washed off a cruising cat by a wave is very unlikely and capsize even less so. We prefer the security of a locking biner and the Tango is a quick-open compromise. However, there have been a number of drownings of sailors dragged by tethers or on boats that capsized; monohull, sport boat, and performance catamaran sailors should have quick release snaps at the harness end. However, be warned that most tether quick releases have failed in testing and in the real world to release under load . Test by hanging before you buy! Practical Sailor is investigating this issue. If your boat can capsize or is narrow and washing off a possibility, use a quick-release shackle.
  • One leg vs. two. Vital, as most boats need a short leg on the side decks and at the bow, and a longer leg around the mast. Though I played with 2 versions for some years (the conventional 2-leg version; a 1-leg version with an intermediate clipping eye at about 65% length) we have settled on the 2-leg version as handier. Do NOT clip the unused leg to you harness; clip it to the eye below the harness shackle. In the event of a capsize you will find that releasing the harness tether has left you clipped to the boat via the unused leg!
  • Shock absorption: Screamer. Notice the Screamer at the harness end. A simple $18.00 gadget that ensures the impact force cannot pass 600 pounds. I've broken ribs snowboarding and don't fancy doing it again. Climbers have been using these for many years, and ALL industrial and military tethers use them. Because they are easily replaceable (larks head to the 2-leg tether and overhand loop on the end of the 1-leg tether), triggering one is a minor expense (they are still full strength after triggering but will no longer absorb impact). I thought about only using the Screamers on the fixed-point anchors, but decided a fall over the side could be rough for me and that they were not in the way. This feature is NOT yet commercially available, though prototypes are being field tested.
  • Shock absorption: Dynamic Rope.  8-10 mm dynamic rope is another excellent option. Read this later post. The advantage of dynamic rope is that it can withstand multiple impacts.
  • Fit to boat. I think it is a mistake that all tethers are 6 feet or 3-6 feet; there are sound engineering reasons why falls over 6-feet are very serious, but honestly, boats are not one size. Most boats should have a short leg less than 3 feet. Multihulls need more than 6 feet to work effectively on the tramp. This is one reason I make my own. If you feel the need to modify your tether lengths, just be careful. This post may help.
There  does seem to be one potential weakness to having shock absorption installed in the tether; when it triggers the entire tether must be replaced. With a commercial tether, this will be about $200.00. There are 2 things I've asked the manufactures to consider:
  • The Screamer section should be replaceable. Then it is only a $20.00 fuse.
  • If the Screamer is non-replaceable, it must be protected from wear with a single bar tack. I have already learned that repeated non-critical impacts tend to loosen the stitching. This is not a safety concern, but in heavy duty use (Volvo?) it will reduce the effective life.

If this is something you would like to see on the market, call Yates and ask for them! They've built prototypes, but demand is required for an idea to make it to market. 


_________________

 Another option is making the tether from a more dynamic material, such as nylon dock line or climbing rope. Let's consider climbing rope. A single rope meeting UIAA standards cannot have an impact force of greater than 1650 pounds (187-pound climber), while a typical modern rope gives a fall factor 1 impact force of more like 1000 pounds. These ropes are rated for twice this fall distance. How does this compare to the Screamer? The elongation is similar; about 2 -2.5 feet. The peak impact force is about double because the Screamer gives steady braking instead of graduated braking. The climbing rope gives lighter weight and greater simplicity.

Thursday, March 29, 2012

Is Methanol Going To Be The Next Ethanol?

Natural gas prices are very low and projected to stay there. There is even talk in the Wall Street Journal this morning of spot gas going to zero by late summer; it keeps flowing from wells (small guys need the revenue and many wells co-produce oil and gas or natural gas liquids), storage is limited, the winter was mild, and export facilities are limited. Inventory is running far higher than normal. Day by day and more and more it is becoming clear that gas recovery by directional drilling and fracturing has cause a paradigm shift in our energy outlook.

Methanol is made from gas, and gas is very cheap and likely to stay that way for decades. The politics are pushing us that way too; gas producing states, voters wanting cheap gas, and policy makers seeing energy independence are all raising the issue, an there is no doubt far more behind-closed-door activity:
http://www.nytimes.com/2012/02/24/op...-gasoline.html

The gasoline distributor recently filed suit against the EPA asking for relief on the coming ethanol blending requirements; it seems the law requires more ethanol than can be practically produced. And there is a good case against the environmental benefits of ethanol farming.

Apparently there are bill before Congress to require an "open fuel" standard by 2017.
http://rtec-rtp.org/2012/03/10/methanol-has-momentum/

Certainly methanol has it's weaknesses; I don't wish to flog that horse. But does it have weaknesses in the marine environment beyond those of ethanol? Water tolerance is one, and perhaps a major reason MTBE was used in place of methanol years ago. Add just a few drops of water and, BAM, the methanol layer falls out. It is not, by itself, a stable fuel. However, it seems that used in combination with ethanol, that problem may not be too serious...
http://web.anl.gov/PCS/acsfuel/prepr...04-90_0276.pdf
... and most of the gasoline pool has 10% ethanol or will soon. Just the ethanol we are already blending should be enough to stabilize the fuel.

There is also good information here:
http://celanesetcx.com/wp-content/up...ine-Blends.pdf

Enleanment may be the most formidable problem i the total alcohol content rises about 10% or even in 5% ethanol/5% methanol blends; methanol has less heating value than ethanol and like to run richer. It would seem new marine engines and outboards will need to become flex-fuel, just like cars. I expect materials compatibility issues as well, as methanol is more corrosive than ethanol, but that may be solvable with corrosion inhibitors; that technology has also improved.

I think it's quite possible we'll be seeing methanol/ethanol blends used to fulfill the EPA regulatory mandate. When? I'm sure it will be some time, but it's not to soon to look into the challenges.

Saturday, March 24, 2012

Morse MT-3 Engine Controls

These have always been a bit of a mystery to me. The manual suggests annual lubrication--probably not needed on a PDQ 32, since they are under cover--which I never did. There are no visible fasteners and the direction always made it sound like major surgery, which I have been avoiding with some guilt until...

... I prepared to leave my anchorage this morning and the starboard handle fell limp. Oh, it would shift gears and felt normal when doing so, but the engine wouldn't rev. If the handle was pulled out as you do to adjust the throttle with the engine in neutral, the handle was limp. When I removed the engine cover and moved the throttle from there, everything felt normal and the engine was fine. I could only assume I had torn the head off the cable or that some crucial and unobtainable small part had disintegrate. Visions of boat bucks melting away filled my eyes.

Opening the control for a better look turned out to be easy:
  • Leave the handles on. They aren't in the way and will help with trouble shooting.
  • Remove the 4 screws that hold the control head to the bulkhead. Lift about 2 inches.
  •  Remove 2 screws about 3/4-inch below the mounting flange, one fore and one aft. Both are in recesses and hold the cover haves together. No other fasteners need be removed and no spring-loaded parts will fly out.
  • Pull the 2 halves apart. While you're in there, grease everything, including the exposed cable. In my case, after 14 years, the factory grease was just running thin but not gone; however, in more exposed locations, lubrication every year or 2 would be smart. Check for loose bolts--I found a few. 



The problem was delightfully simple. An E-clip (a type of external retaining ring) had fallen off of the throttle control lever and allowed the cable to come free from the control. Why? In part, because a pair of screws retaining the cable end had loosened and allowed the cable angle to change. In part, because the clip was stainless and not all that strong. I replaced it with a spring steel clip, buried in grease.

Carrying a few spare clips might be smart (5/16-inch E-clip--be aware these come in 2 thicknesses and that the thicker ones will not fit the shaft grove). The motor end controls are also 5/16-inch clips (a different design, and I have had failures there as well--the same E-clips will fit).

Friday, March 16, 2012

Carburetor Bowl Vent Canister

rev. 4-29-2012

Surely it appears I'm going overboard on this topic, but I love experiments.

If a carbon canister can reduce fuel loss and water gain in a tank, why not address the carburetor? Wouldn't this reduce gum formation and ease starting? And since it won't cost me anything but time in the shop, isn't it worth a go? Tiny carbon canisters have been fitted to California lawn tractors for some time, to meet stringent air regulations.

In automobiles evaporation emission systems tied the carburetor vent--back when we had carburetors on cars--to the main canister and flushed the system with intake air during operation. More efficient in terms of hydrocarbon destruction, but more complex and only effective if the car ran nearly every day. In fact, those systems did not reduce carburetor bowl evaporation, since they would never reach equilibrium. They actually drew gasoline from the bowl, much as calcium chloride draws water from the air. I've taken a different approach, since evaporation reduction is a primary goal, and that requires that the carbon reach equilibrium with the carburetor bowl while the engine is running, exactly the opposite sequence from what automobiles systems achieve. Since the carbon is saturated during operation--a warm engine encourages plenty of evaporation--when fresh air tries to enter the carburetor when it cools and at night, that fresh air will become saturated with gasoline vapors and will not contribute to further evaporation in the morning. This process of self-regeneration is about 65% efficient in reducing emissions for long time periods, according to EPA testing (page 5-120).

The carbon canister is above the in-line fuel 
filter and is connected to the carburetor vent hose.
Click to enlarge.

The canisters I installed are retrofitted from small in-line gas filters from the might-need box. Originally, they contained fritted bronze elements, which I had discarded (these were replaced by Raycor filters). I fitted each end with a carbon support screen cut from beach cat trampoline fabric. They hold 6 ml of granular carbon of a type optimized for low-flow gas phase  hydrocarbon adsorption. Though small, the carbon:gasoline volume ratio is much greater than used on tank vent filters, this is intentionally so; these will see much greater temperature operating temperature range because they are mounted beside the engine. Even the diurnal cycle will be greater, since the carburetor lacks the thermal mass of a fuel tank. They are NOT secured directly to the engine, as the high-frequency vibration is not good for the carbon. It is extended away from the carburetor, horizontally and slightly down hill, with 6 inches of hose to prevent fines from migrating back into the bowl. This is the existing hose, previously open ended and routed downwards between the carb and engine block.

What do I expect? Easier starting. Less idle jet gum formation and fewer stuck floats. I'll let you know.

___________________

Follow-up reports: 
  • Baseline, March 18. Both engines require primer to be pumped up if the boat has been help for a few days. Port requires 1-2 pumps of the throttle (Yamaha 9.9s have an accelerator pump). Starboard requires several pumps and several efforts, followed by an advanced throttle for a few minutes. Engines re-start within 18 hours, even if cold, with a single crank and idle well. Both engines are identical, purchased at the same time except for the carburetor; the starboard is a fixed idle jet US carb, and the port is Canadian with an adjustable idle screw.
  • March 25. Easier starting after a week away seems to be confirmed. Both engines start on the first crank, without pumping up the primer or pumping the throttle. The starboard engine did not require the throttle to be advanced during warm-up and did not stall.
  • April 20. Up-graded to 1/8-inch thick FRP filter with silica gel/alumina fill. This adsorbent has been performing better in bench trials when high humidity is considered. Very sturdy, better fit, easier to mass produce, twice the adsorbent volume. Non-refillable, but projected life is 5 years.

Sunday, March 11, 2012

High Blood Presure

Though I've always been healthy as the proverbial horse, my blood pressure has always tended to the high side, and now passing 50 years, it crept past 140 over something. So a month ago I started on a minimal dose of Lisinopril. Now it's below 120 over something and the doc is thrilled.

It's not diet. It's not weight. It's not lack of exercise. My doctor was clear on these things. It's just Mom and Pop and time. Fortunately, my cholesterol is very low and heart disease is unknown in my family. But If I want to make my family's customary 90 years in good trim, I need to maintain the house.

I read some posts from folks who claimed Lisinopril negatively impacted their athletic performance; that's not been my experience. While I always ride just a bit slower in the winter--my lungs don't like the cold air when near maximum effort--if anything, the pace seems to have improved. Perhaps that's only because spring is coming, but I certainly don't feel worse. No one's been passing me, not even the young punks (anyone under 35).

So what if I'm an old fart. I'm figuring on another 40 years, so there.

Thursday, March 8, 2012

Reefing Luff Blocks

Rev. 4-24-2014

Larger sails often come with these. While not strictly needed, I find this reduces the friction a bit



  • The long 1/4-inch shackle provides space for the webbing that a bullet block would not. Stronger too. The shackle must be just the right width (1/2-inch); some are wider and the rope could jump.
  • The webbing bit is an 8-inch climbing sling from REI, something I had retired from climbing use. You need this length to get the block clear of the luff.
  • The blocks are self-contained Harken Bullet sheaves, left over from a prior project that didn't work so well. Always recycling.
  • I did drill out the inside of the blocks just a touch. About 1/64-inch.
_________________

Note 4-24-2014: After 2 years of use, the block on the 2nd reef was crushed. Too much load. I replaced it with a solid sheave turned from HDPE. No further problems.