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CS17 mk3 hull #3 "Carlita"


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The "pressure treated" stock now available (retail) isn't well suited for epoxy. If you can the commercial grade stuff, this can be ordered (or in stock) as the old CCA treated stuff, which does take to epoxy well. The CCA treated "PT" was pulled from the retail market a few years ago, replaced with a CA treatment which tends to clog the wood's "pores" preventing epoxy from getting as good a grip, as it did on the old CCA stuff. Epoxy will still stick to this new(ish) CA treated PT, but just not as good (about 50% less peel strength).

 

Most big box PT stock is SYP or Douglas fir, but unfortunately it's also farm raised and has very wide growth rings, is full of defects, pith and other unfavorable attributes. It's the redheaded stepchild of good SYP, but if you pick through a pallet or two, you'll find some tight grained stuff that missed the inspectors.

 

Was I yelling?

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No PAR, you were playing nice. I always appreciate your practical knowledge.

 

I've also wondered about the "composite" ( http://www.lowes.com/pd_371963-46086-229074___?productId=3612032&pl=1&Ntt=composite+deck+boards ) for rubrails. I have no idea about bonding with epoxy or paint.

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There are several types of this "composite" decking stuff. PVC and recycled milk jugs seem to dominate, but there's paper and other materials too. The "Choice Dek" stuff is recycled milk jugs, mixed with some UV inhibitors (not much) and some virgin material. They're not structural materials and can't even support their own weight in longer lengths. They "age" and weather to a degree, but remain fair tough for many years. Good for an abrasion strip and a well fastened rub rail. These materials don't have very good fastener holding power, but if they're screw to something else, will do fine. They can be epoxied, but they need to be "caramelized" first.

 

I'm in the bedding crowd. To me the rub rail is a sacrificial, consumable item. It has an inwale bearing the loads, though the rub does double it up, it also gets the crap beat out of it and needs to be replaced every so often. Fasteners and bedding make this much easier. If it's glued down, it's now just a bump in the flanks of the hull shell, married to it, so replacement is more problematic.

 

I was just wondering about the "hollering" thing, that's all. I don't holler all that much, my kids are old enough now, there's just not a lot of need any more (damnit). I've never been much of a hollerer, except when married to the masochistic sociopath, just out of high school.

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I wish teak wasn't so darned expensive. My Sea Pearl (similar weight as these boats) has a Teak rub-rail. It's been on the boat since new (1988) and still looks awesome. It gets dinged a bit, and every few years I sand out the scuffs and dings and oil it, and it just gets it done. But last time I looked at my local boutique lumber store (Pittsford Lumber) it was scarce in longer lengths and not affordable. Is there an affordable oily type wood like this that would look good and hold up as well?

 

I am reluctant to add a metal strip. I sail with a lot of guys who have pretty nice boats and I don't like being the hammer rafting together as stuff sometimes happens. I have a Sea Ray powerboat that has a rubber-ish rail that is awesome. When the kids bring sailboats and kayaks and other boats next to it it protects both. I definitively like what Jay has done to his.

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Jay's rubrail is probably the best solution. Teak is running at about $30.00 a board foot which is a bit rich for me. Afromosia looks something like teak and is often substituted for teak. It is probably harder but is not as oily as teak.

 

I am using some mahogany that I have hoarded for a long time. It will be covered with stainless hollow back. Because I will be showing my boat a lot I feel the need to go with a "yacht" finish rather than the more practical "work boat" finish.

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Graham, the rubrail  used on Southern Express is on SALE at Fisheries Supplies.  Boat and sale, two words that can have many meanings.....  Southern Express is sailing just great, I did a rework of the main hatch, the lift up hatch I had was causing too much pain on my balding noodle!

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Hi Dale, the name brand is called Tessilmare Radial 30. I used the smallest size in white. It is quite resilient, we tried to go into a waterside restaurant last week at late night, and got blown up on a pile that was short and backlit so I could see it. Worked good!

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All,

 

Graham and I took Carlita out for a sail yesterday to further evaluate the tacking angle of Graham's CS17Mk3. 

There is no current in the Bay river and the wind was a gusty as always in the river but more steady to the eastern side with greater fetch. The boat was a joy to sail and it was my first time at the helm. She is very stiff with the water ballast and we were full sail the whole time. She would lay over but only to a point and then just drive on upwind. Graham and I and the two dogs stayed nice and dry the whole time in the cockpit which was wonderful. Like a magic carpet ride. 

 

As you can see, the tacking angle is not really that bad. To a seasoned racer it may be frustrating at times but for anyone going out for a pleasure cruise which after all this boat excels at, the boat is no slouch and didn't have any trouble going to weather just to keep the discussion in perspective with some real world testing. 

 

The red angles we determined to be "outliers" and didn't include in the average. 

 

In the second picture, you can see Graham tacking into the third checkpoint in the EC and deciding to take the southern route. We think that he had some favorable current in this stretch because we can see that his speeds over ground were about the same as in our afternoon sail but the tacks are compressed consistent with favorable current. It may also be the case that in the heavy air conditions and being reefed down, Graham had the boat more dialed in for upwind work that we had yesterday. 

 

The third picture is from this past saturday when Graham went out sailing with Vlad (AKA Crazy Russian) who was helming the boat in light air conditions. Tacks show decent performance here too. 

 

bay%2Briver%2Btacking.jpg

 

tacking%2Binto%2Bflamingo.jpg

 

light%2Bwind%2Btacking.jpg

These results pretty much coincide with my experience. I've got lots of GPS data on Bandaloop and find that when I'm sailing well (watching the tell tales very closely and correctly trimmed) that we get around 102 degrees COG between tacks in flat water and 8-10 knots of breeze. I find in really light air the angles increase a degree or two. 

On the same stretch between East Cape Sable and Flamingo, a couple of hours before Graham went through we averaged 106 degrees COG between tacks. We may have had some tide against us, but I don't know that for sure. 

Once we got south of FL Bay and upwind into 25 knots between Arsenic Bank and Bowlegys cut, the waves were often 2-3 feet and really short. In the dark in those conditions we only managed 123 degrees between tacks. Bashing into big, square waves that almost stop the boat appears to have a serious negative effect on leeway. 

Both EC examples are with main and mizzen double reefed and winds 18-25 knots. 

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Technically a bigger main and smaller mizzen would be slightly superior upwind to the mk1 rig. There are many compromises to consider when designing the rig but the main reason that I had to move the mizzen further aft was so that the boat could be rowed.

 

If one carried that logic to it's limit, you would dump the mizzen and go cat rig. Then you would give up the wonderful handling characteristics of the cat ketch rig.

 

This was another reason that I leapfrogged the mk 2 and did a completely new boat for the mk3.

 

John, I noticed that I had a favorable south flowing current as I worked south to Cape Sable. I never saw anymore crab pots after I turned east but studying the behavior of the whitecaps I wondered if I could be lucky enough to get a fair current in both directions.

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