Monday, August 27, 2018

Spare Yamaha 9.9 High Thrust Props for Sale

In the process of making room for more boat stuff, I came across these, which should go.

Used, but functional. In my opinion, every PDQ owner should carry at least one spare, if not two. Once in a while you will wind up a lift line or find a crab pot. It's a 5-minute change... if you have a spare. I always carried a spare.

They're ~ $70 on e-bay. How's about $50 for all three, plus whatever shipping costs (unless you pick them up, either Vienna, VA, or Deale, MD.

Time for Bed

Tuesday, August 21, 2018

Depth of Discharge vs. Battery Life

It's a cruiser mantra that lead acid batteries should never be taken below 50% state of charge. There is some pretty convincing math on this for batteries that are cycled daily,including full-time cruisers and off-grid power systems. On the other hand, golf carts go lower than that every day.

And for the rest of us, who cruise weekends and a few weeks now and then, we don't rack up that many cycles, perhaps 100 in 5 years and 200 in 10 years. Northern holiday cruisers are even more challenged to rack up high cycles, with the boat out of the water half the year.

Even using shallow cycle designs, which we are not, we'd be hard pressed to hit the cycle limit within 10 years if we took them to 60 %, and we would just hit it in 5 years at 80% discharge. With standard deep cycle batteries, we could discharge to 80% far more times than we will ever spend the night on the hook. The batteries will die of corrosion, failure to recharge, or failure to water first.
This has been my experience. I use relatively small battery banks and discharge past 50% regularly. I do recharge as soon as possible and I do check the water. I typically have gotten 7 years, whether cruising frequently or not, before I loose enough capacity I replace them (never complete failure, such as a shorted cell).

Why what some would consider an undersized bank? Because on a multihull, weight is worth money. My boat cost $20/pound and I feel every pound saved is worth $20 in performance. Otherwise, I would have purchased a slower boat. Carrying an extra battery (75 pounds) costs $1500 in weight penalty.First, I don't believe adding a battery would extend the battery life in proportion to the added purchase cost; they would last perhaps 15% longer and cost 25-50% more to replace. The $1500 weight penalty stands. The only upside is additional reserve capacity, which isn't worth $1500 to me.

(That's 25 degrees C, not 250C like it says)

I've had enough different boats to understand that for each boat, my answers to these questions would have been different.
  • How big is the bank? A single group 24 battery is minutes to change, but a big bank of traction batteries is a project.
  • How critical is power failure? An outboard can be pull-started, a big diesel is a problem.
  • What charging sources are available? How many days between full charging?
  • How often is the boat anchored-out? Are we talking thousands of cycles or hundreds during the life of the battery?
There is simply no way that one answer is right for everyone. On my last boat battery maintenance was serious; lots of appliances and significant battery cost. On my F-24 weight matters, I have one slim 50W panel and a throw-away group 24 battery. I don't have any electronics that matter to me and I pull start the engine. A 5-pound Li ion battery is probably the smart answer, providing all the power I need for about the same money. Very cool.

I need to look into this farther.

Saturday, August 11, 2018

Dual Rod Holder From Scraps

Or rather from a stern rail motor mount that the the PO liked but I had removed. In my mind, either the engine should be able to stay on the dingy or...
  • The davits or hoist is weak. Upgrade.
  • The engine is too damn big.
  • The dingy moves too much, in which case it should be triced-up.
  • The dingy is vulnerable in rough weather. Not the case on most catamarans, since the davits are forward of the transoms.
The mount has been resting in a might-need drawer for 6 years but now enjoys new life.

It's primary purpose is to hold my 2 mini-outriggers (2 x 6' outriggers give me an effective beam of  26 feet, easily trailing 3-4 lines without tangles) while not trolling. They can't left in place during docking, and placing them in the outboard rod holds inhibits easy boarding and blocks the holders for other uses. I find rod holders handy for other things as well--boat hooks, walking sticks, gaffs, oars--so i can never have too many.

I dislike commercial holders since they only grip the rail without twisting if tightened so much they scar the rail. This never will, since it uses an up-right for bracing.

Construction was simple enough. I had to slot the back to accommodate a brace. The 2" SCH 40 pipe is attached with counter sunk #10 machine screws. In the background are a pair of kayaks lashed to the top of the davits, the most convenient storage space.

The lures are home-made too.

Thursday, August 9, 2018

Sun Protection

The sun is a real bugger in the summer. I realize I was spoiled by the big hard top on the PDQ, now that I'm baking in the sun once again.

The water is wonderful, but the air is steamy.

Earlier this week, after enjoying a nice sail, I decided to anchor for a bit in the falling breeze, to eat lunch and eventually do some paddling along the coast. The first thing I did was rig an awning, which was a life saver.

I need to fine-tune the pitch, but this nylon tarp keeps the sun off. Notice some chipping of the paint.

I made it up 10 months ago out of a blue nylon tarp I had. Itis attached to the mast and topping lift, with straps around the shrouds and posts fitted to the stern pulpit. I didn't set the back corners  correctly for this image (I forgot where they went), but you get the idea. The white paint is nothing more than a single coat of Behr from Home Depot, casually slapped on; I learned from another boat that white really drops the temperature.

Which brings us to sails. Every self-respecting furling genoa has a sacrificial UV strip, usually Pacific Blue Sunbrella (which the sailmakers call "everybody blue"). It lasts until the stitching fails, generally about 5-8 years. You can either restitch it for another 5 years, or have it replaced for $400-$800. It's heavy but durable. Some folks use sail cloth or self-adhesive Insignia Cloth from Bainbridge; a waste if you ask me, since they only last 3-4 years.

And then there are light air sails, like this furling laminate reacher, that have no UV cover. We don't leave it up, partially for this reason, and partially because we don't use it most days. But it would be nice to leave it up, if only it had some protection....

You won't see me sewing a UV strip on it. Stitching a Mylar sail is like adding a tear-here perforation.

This jib suffered a 5-foot tear right along the stitch line. The cover was post-factory and the sailmaker that added the cover was an idiot (you need to insert a special scrim or layer of polyester before stitching Mylar). 

 We also know that paint can stick to sails. This is for advertising, not UV (mostly--it must help), but it does last a year.

Can paint provide a serviceable, light, and economical alternative to Sunbrella UV covers? Maybe it won't last as long, but on an older sail, does that really matter? Perhaps the $600 you save is more wisely earmarked for a new sail in 4-5 years.

I'm lining up some test paints. I think you will see a paint UV cover on my reacher in a few months. We don't leave it up much, so I'm sure it will be enough. I doubt the UV cover will ever fail on our Mylar genoa--the sail will explode first. Would I use paint in place of Sunbella on a new polyester genoa? Probably not, but perhaps for an old dog. On a Mylar jib? Yes, I'm thinking it might be the better value, if I can find the right paint. I already know that stitching a cover onto Mylar is questionable at best.