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 $2.95. (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.
The knot is just for illustration. This weakens the webbing below spec.

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 anchors. Don't tie rope or webbing directly; though polished to eliminate sharp corners, the radius is really 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.

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.

The Devils Tattoo

Sleeping on the boat, even just at the marina when lacking the time to go anywhere, is one of the great joys of owning a cruising boat. Quiet time.

And then it starts. At first, just an isolated sound. Ping. Silence and a few waves lapping. Then increasing. Ping, ping. A few seconds of rest. Anticipation. Ping. Ping, ping, ping. Pointless urgency. Ping, ping, ping, ping, ping,
ping.... Restful like a train station.

I've head the that the gentle slap of hemp on wooden masts is soothing, but my expereince is limited to the shrill ping of polyester on aluminum. The creak of docklines is OK; they can always be adjusted if troubling. The low howl of the wind is calming; I'm harbor, not underway, so all is right in  my corner of the world.

And then there is the matter of chafe on halyards and lazy jacks and scuffing of the mast. I tie mine off by sliding a loop up the halyard, pulling it tight to the diamond wires. Most noisy masts have a plan, but just a fair weather plan, a plan that fails, unknown to the owner, when the wind pipes up. Bungees lose tension. Lines stretch. 10s of thousands of cycles against the spreaders, jacklines, and the mast itself. It all sounds like money to me.

--------

Today I've been fitting a new windlass to my boat, swapping a badly rusted Lewmar Sprint 500 for a V700. Very quiet. The windlass that is; the winds have been sustained at 30 knots at the dock, raising all sorts of racket.

I can't afford halyards this year.