carcrash

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About carcrash

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    http://www.Westlawn.org
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    Cabrillo Beach YC, Waikiki YC, Grenada YC, LA, NY, and Maine

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  1. carcrash

    The 2018 Golden Globe Race

    Thankfully, nobody needs to depend upon your thinking besides for the humor, which many of us enjoy. Keep it up, Jack!
  2. carcrash

    The 2018 Golden Globe Race

    And Regarding an aluminium yacht that has beaten around the Southern Ocean: No. Hell no. Aluminum fatigues to zero strength. Do a short experiment with an aluminum can. Even small amount of flex, hundreds of thousands of times, does it in. One lap around the planet upwind over 120 days is 12 x 60 x 24 x 120 = over 2 million. The boat would need to be very over built, with a design impulse load of under 10ksi, to be reliable, and any welds would be quite dangerous. Consider that absolutely no part will be an inch thick! Quarter inch thick, 2500 lbs stress... Steady loads might be less without headstay tension, bit the impulse (shock) loads from each and every wave with upwind rigging and sheet loads will be much higher. And of course, there WILL be corrosion weak spots too. If it was steel or fiberglass, a different story.
  3. carcrash

    Ballast v Draft

    Ask a naval architect. You will need one in any event to actually draw up the keel, keel bolts, and ensure the structure will take the load. Big difference in keel structure loads when you go from an IOR era trapezoidal, high VCG keel to a modern low VCG keel. On my Olson 40, and another nearby, when the keels were changed to bulb keels, the floors (structural members that spread the keel load) had to be substantially strengthened. On mine, the naval architect that designed the keel also stipulated strengthening the structure, but that work was not done even after the NA pointed it out to the owner in the immediately post-modification inspection. The owner scared the crap out of himself when the keel nearly fell off well out in the Pacific. Two other naval architects were consulted on strengthening the structure, and all agreed on what needed to be done, and it has now been done. A similar process was followed on the other Olson 40 with bulb keel nearby. Don't cheap out on keel modifications, especially when it comes to structure to keep the keel attached and the boat afloat and upright. Pay for the appropriate expertise, and live a long happy life. Or not.
  4. carcrash

    Really... Is there a better boat for the money?

    Greg and Teri Weeger sailed their 473 around the world. Here are a couple of paragraphs copied from the Latitude38 article linked below: "She's been an excellent boat, and we had no major problems with the hull, rig or anything else," says Greg. Not that it surprised them. Back in '04, the couple did the 600-mile Sydney-to-Hobart Race, perhaps the world's consistently nasty middle distance race aboard a mini maxi Helsal II. The '04 race turned out to be so rough that the 100-ft maxi Skandia had to be abandoned, all the ribs were broken on the 90-ft Nicorettewhen she crossed the finish line first, and the mini maxi the Weegers were on broke and had to drop out. But, the Weegers took note, all five of the Bennie 473s in the race not only finished, but did well in the standings. A long time racer, Greg says he's spent a lot of time working on performance polars. "For this trip," he laughs, "I made a set of cruising polars. If we weren't making 5.5 knots toward our destination, we turned on the engine. We had to because we were on a schedule. As a result, we actually spent more time with the engine on than we did under sail only." https://www.latitude38.com/changes/Changes09-09.html
  5. carcrash

    Pukers United – For those that have

    Not that I have seen. Never needed to eat a million of the things, just a few seem to do the trick. I don't often get seasick, but when I do, this antacid trick works, and seems to work for anyone aboard who tries it. Of course, combined with the normal behaviors: avoid diesel fumes, have roles that require paying attention to the horizon, stay on deck, easy to digest and quick to prepare meals, etc.
  6. carcrash

    Pukers United – For those that have

    Rolaids or similar are simply magic. Chew one when you are on the weather side about to head for the leeward rail, and by the time you get there, its all calmed down. Repeat as necessary.
  7. I would strongly suggest a boat with a tiller for cruising. When not moving (anchor, mooring, marina), you can lift the tiller up and get it out of the way. This makes a huge difference! When moving, you will very often have the autopilot on, so again, the tiller can be lifted and out of the cockpit. Again, making a small cockpit dramatically nicer. And of course, a wheel provides all sorts of horrible failure modes that tillers do not share. Tillers are very easy to repair at sea compared to a wheel. For cruising, where an autopilot is important (almost critical), you must have an under deck autopilot, not a tiller pilot nor a wheel pilot. Adding a quadrant to a tiller steered boat is easy. Putting the autopilot drive on an existing wheel quadrant might be actually harder, because wheel quadrants tend to be low in the bilge. Here is my autopilot quadrant. There is a slot, with a bolt, which limits the rotation of the rudder shaft. The tube covering the rudder shaft was cut away about 6" or a foot to expose the rudder shaft, and the quadrant was bolted over the rudder shaft. There is a big aluminum shelf bolted to the aft side of the cockpit, and the Octopus electric/hydraulic pump is bolted to the shelf, with the control rod end bolted to the quadrant. There is a rudder angle indicator (the small tan box). The octopus drive is here: http://octopusdrives.com/linear-drive-family and it connects to just about any autopilot head: octopus is sold by seemingly all autopilot vendors. The specific model I have is 1012.
  8. carcrash

    Olson 40 For Single Handed Blue Water Sailing

    I have such a bad case of the flu that I have not been able to do a sea trial yet. I'll post performance soon, but with the forecast of rain this weekend, might be another week or three. It's a pain working on the boat in the rain, as I have no dodger yet. It hardly rains in Southern California, except this time of the year.
  9. carcrash

    Olson 40 For Single Handed Blue Water Sailing

    Batteries: https://battlebornbatteries.com/shop/100ah-12v-gc2-lifepo4-deep-cycle-battery/ 100ah x 48v so about 5KWh. They are light (31 lbs each) and I have a lot of room now where the exhaust and fuel tank used to be, so it will be easy to greatly increase bank size as battery prices continue to decline. I put four of these in to replace 4 T105s. The new 4 are in series to make 48v, the old T105 bank was 2x6v in parallel for a 12v bank. 225Ah x 2 so again about 5KWh. However, drawing high current out of T105s reduces the effective available power enormously, with experiments showing as little as 500Wh when drawing at a 5KWh rate (10 minutes to flat batteries). So the Trojans had to go, they just would not work. For 12v house loads, I use a 48v to 12v "buck" converter. https://www.amazon.com/360W-Converter-Voltage-Regulator-Waterproof/dp/B07J274LZD/ref=sr_1_1_sspa?ie=UTF8&qid=1547148391&sr=8-1-spons&keywords=48v+to+12v+30a+buck+converter&psc=1
  10. carcrash

    Foils fail.

    The only way things won't break is if they are so over built the boats will never fly. Models, as used in engineering, are not based on "first principles" ever. Many people think so, many people claim so, but it's just not the case at all. All models used in engineering are approximations over a limited domain. If you are in that domain, they can be pretty good. If you are out of a well known, extensively proven domain, they are simply fiction, at best misleading, at worst leading people into truly unworkable approaches. Since there has never been vessels built like these, the useful models do not yet exist. It's not just that the models being used before construction are somewhat flawed. They are simply not correct. Example: If all boats have L/D ratios over, say, 300, like fishing schooners or clipper ships, then the square root of waterline is a pretty darn good model of performance. We all know that there are many other factors in speed. For boats that look like IRC boats, the IRC formula that includes very many factors is a much better model for performance. Science is required to do what has not been done before. Engineering is effective to do what has been done very many times before. So these boats must be developed by science, not by engineering. Science requires hypothesis (which are often suggested by models), that are then demonstrated to work or not via experiments. The destructive tests are one sort of experiment, and if failures are not occurring, then the models being used are too conservative. The edges of the performance envelope must be discovered: this means they must break, or no learning is achieved. As several people have mentioned, the dynamic loads are the interesting part of the problem domain. Static tests are quite easy to do, as done on airplane wings (expensive facilities are required, and the destruction of large highly loaded expensive structures are also required). And this is sufficient for airplane wings, because people have been building airplane wings for a long time (its engineering, the models are refined). Dynamic tests, where the loads are in any direction with dramatically varying rates of change to force magnitude and direction, is extremely hard. The useful models do not yet exist for this domain. They will come from the experiments. The experiments require failure, to determine the performance envelope, and therefore domain of applicability of the models. So the thing I have been surprised about is that TNZ seems to think that they do have good models, and that the boats will work when splashed. I think T5 and Mule demonstrate that at small scale, small loads, the models are not too bad. The crashes T5 has done, and that I am sure Mule will experience, are part of generating useful models for control. Model development can be rapid, so I think they are going to get a handle on everything in months. However, the structural and performance models will also take awhile to converge, and plenty of breaks will occur as these models are improved. TNZ has demonstrated their ability to truly do science, which is why they flew the AC72s first, and why they were so much faster in the AC50s. So I have high confidence in their eventual discovery of how to do this. And I am not at all surprised that failures are happening in this experimental phase.
  11. carcrash

    The new sailing twin skin setup

    A free standing wing mast that can rotate 360 degrees is MUCH less aero drag than a small section spar held up with wires and spreaders. So would be MUCH better at the dock. There is a reason that zero production aircraft have been built using single or double skin soft wings in the past century, and only aircraft built for weird flight envelopes (slow and rugged: e.g., Pitts, Cubs, C150) have been built with wires and/or spreaders in the past half century. So the double skin sail is a silly, silly development. Airplanes tried it, and moved to "free standing wings." It was explored in C class during the 60s by people including Steve Dashew, and was much worse than a wing, and showed no advantage over a rotating spar with fully battened sail. Hence C class cats, who can do anything within a given area, only use wings or single skin sails since that time, and only wings once they got light enough. Now sure, better materials today, but that improves the single sail more than the double skin sail, and wing much more than either. Especially when one includes the strength and therefore weight of the platform (boat): fundamentally lower on the solid wing, over using very high tensions on a soft sail (single or double). Someone specified a couple of requirements -- monohull, ballast for self righting, sails that can be dropped. These were simply stipulated requirements, none were specified to achieve ultimate performance or especially bang for the buck or practicality. Sure, more practical than a wing held up by wires, but that is just stupid anyway, a concept for going much slower than 70 knots over the deck. 20 or 30 knots, sure, but not 50 to 80 apparent. Foiling is different. A solution that looks sorta the same is wrong. As the future will prove.
  12. carcrash

    Just got the letter....

    Tariffs are taxes on consumers. So a big tax cut for the wealthy (including inheritance taxes, essentially re-enabling the aristocracy), combined with a huge tax increase for the poorer people (who consume most of their earnings). This is good for the downtrodden, left behind, red state working people? Not a fucking chance. Remember: when someone lies to you, they are not doing so in your best interest. This administration constantly lies to you. What else does one need to know? I am a life long Republican, disgusted by the direction the party has taken.
  13. carcrash

    Olson 40 For Single Handed Blue Water Sailing

    Pulled the diesel, installing an electric motor with LiFePO4 battery bank. Saved 700 lbs! Removed all the smelly stuff. Absolutely no odors below now. Took a month to remove everything from the diesel, a few hours to install the electric motor.
  14. carcrash

    Cruising comms

    SSB is obsolete. Like a VHF without AIS+DSC -- you might raise someone, but not who you want to raise. Original sat phone plus crappy software was, as BJ noted, a waste of time and money, with plenty of frustration on top. Go and similar sat hot spots seem the right tool today for long distance comm, but this is second hand. VHF with AIS and DSC for short range comm at sea. Cell of course when it works. WiFi close in. Certainly, seems a bad time to invest big dollars in old technology like SSB, as literally hundreds of satellites are currently in build and being launched, and thousands more are in process. Within two or three years, we will have global high speed internet at prices that work for very poor countries. If you can wait to spend, you will be spending a few hundred for high speed, instead of many thousands today for snail speeds.