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Scott Dufour

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Scott Dufour last won the day on January 15 2015

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About Scott Dufour

  • Birthday 01/31/1971

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    Bolton, Connecticut

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  1. In heavy weather, I mount the rudder upside down and use it as a windvane. Always thinking outside the box, I am. Actually, Peter's right. That rod is loose right now. It is the pintle material, but not the pintle placement. Incidentally, the set is still available. Rex and I thought he might be able to use it, but shipping to Thailand from the US East Coast is prohibitively expensive.
  2. That sounds like a job for a marine engineer, doesn't it? I think that I'm way out of my league there.
  3. Hey Howard, Yup. I made them. They're just stainless plate, 316, worked on my vice. They still need a welder, though, to close up the point where they pinch together and to weld on the pin to turn them into proper pintles.
  4. Are you thinking steel? I'm pretty uninformed for this kind of structural analysis with metals. What's the grade of steel (I'm assuming not stainless) that's appropriate for this? My quick calculations show that it could be 219 lbs of A131 ABS steel, or maybe as low as 100 lbs 6061-T6. Would aluminum be recommended for this, given the machining nooks and crannies required and the potential for corrosion?
  5. Hey Greg, If you want a head start, I've got the tiller, centerboard, and rudder all ready to go. Shipping from Connecticut to Michigan shouldn't be that bad.
  6. Hi PAR - you are exactly one of the brains I was hoping to pick. I've considered it a metal tabernacle - but not seriously yet. I'm certainly willing. Are you suggesting it to save weight, or bulk, or for more certain strength? I've been thinking wood because: I have plenty and I know how to work with it and epoxy and fiberglass. I don't know how to weld. Wood in the interior is nicer than metal. I like the sound dampening properties of wood - disconnecting the metal mast from the interior by way of softer material like ash just seems a good way to quiet some of the noiser elements of all those junk rig battens. Not that they should bang all that much if I've designed the combination batten/downhaul parrels correctly. I've just gotten rid of all chainplates and other major metal/deck penetrations. That equals no leaks, and no sneaky corrosion hiding in the dark below deck and above headliner. When I pulled those chainplates out, there was a fair amount of crevice corrosion, and I was hoping to avoid that potential. The lowest batten (technically the boom) will be slightly below the top of the tabernacle. It (and the reefed sail bundle) will be inconstant contact with it. This may actually be an argument in favor of metal - a smaller interaction area due to reduced thickness. I'm sure how that's going to work out yet. But... if those concerns can be mitigated, or if I'm unduly concerned, or a hot dipped steel tabernacle has so many other advantages... well, that's why I'm here.
  7. Hey guys, it's been a long while since I posted on here, but I'm looking for some of the smart people's brain power. Life changes made me abandon the PS26 build, but I'm not through with boats. I've got another large project. I have a gutted Pearson 10M, 1979 GRP, 12k lbs displacement. I'm converting it to a junk rig. Not one of those old flat paneled junk sails that won't go to windward, but a Split Rig junk, developed by Slieve McGalliard about ten years ago. My intent is to contribute as much as possible to the testing of this relatively new rig. She will be a serious offshore cruiser, and my home in a few years. I'm also designing to minimize as many maintenance headaches as possible, and enable as much self-suffiency as is practical. Plus, I'm a lazy (as in CS17 ease of sailing lazy) sailor. That's part of what the unstayed Junk rig offers. The venerable Atomic 4 is gone, replaced with an electric motor and a big ol' battery bank. No flushing head - it's a composter. That kind of thing. The junk rig enthusiasts over at the Junk Rig Association are a small but energetic bunch, and they remind me a bit of this crowd here: not overly enamoured with orthodoxy, but sticklers for good design. They've been excellent and experienced regarding all of the rig design elements except maybe one. I've got all the heavy lifting done for the sailplan (mast location, bury, deck reinforcement, et cetera) , and was ready to order the mast when the idea of tabernacle surfaced and I realized that I want one. The weight is a concern, to be sure, but the ability to lower my mast without a crane is just so tempting. But because weight on the deck is never a good thing, I don't want to overbuild it, as is my tendency. And unfortunately, there is an amazing lack of tabernacle design and build information on the internet. Some details: The mast is 6063-T6 10" diameter at base, 4" or 6" diameter at top, wall thickness of 0.25", and 43 feet above deck. That says that I need 4' 3" of tabernacle above deck. It's six feet from the underside of the deck to the mast step. I'd like to taper the tabernacle from under the deck to the step. Some guidance for wooden masts suggest that from the partners to the step, a mast can taper to 1/2 the max diameter. I'd assume that a tabernacle could do likewise? I'm making it from white ash. My back of the envelope calculations say that the sides need to be 1.75" thick (gluelam), making an open square box of 13.5" sides. That's a lot of weight. something line 180 to 200 lbs. And that doesn't include the tabernacle hardware, the epoxy and fiberglass, or other finishwork. The amount of mast that I'm not using (from partners to step) is about 50 lbs. Have I overdesigned? If not, I'm not sure that the extra weight it worth it. I've tried to paste in a table below of the rig's forces a the partners. Not sure if it will show correctly. Disp (lbs) 12273 Disp (kg) 5567 Heel (deg) RT ARM (ft) RT MOM (ft-lbs) RT ARM (m) RT MOM (Nm) 25 1.293 15,869 0.39 21,523 30 1.45 17,796 0.44 24,136 60 2.018 24,767 0.62 33,591 90 1.435 17,612 0.44 23,887 120 0.124 1,522 0.04 2,064 150 -0.984 (12,077) -0.30 (16,379) 165 -1.008 (12,371) -0.31 (16,779) ID (in) OD (in) Section Modulus Stress @ partner 30 deg Heel 10 9.5 0.00049 36,318,061
  8. Hey everyone, I used to frequent this site a few years ago, but have been off the radar. Life circumstances have forced me to abandon my build of a PS26. I do have a beautifully built centerboard, rudder, and tiller completed, just taking up space against a wall in my basement. I posted the build progress on here when I was making them. If anybody is interested, please let me know.
  9. So much work, Peter. And she looks absolutely wonderful. Congratulations.
  10. I love the rope trick - it's probably my my useful decision on Rocinante. I use my centerboard as a depth finder all the time, and the kick-up rudder as a "no foolin' it's really shallow" idiot light. This is over some pretty rocky bottoms, too. And they have taken very little wear in spite of this abuse. And so easy to make and repair.
  11. Thanks guys - I'll give Graham a shout.
  12. Oh, boy, CRL. Now you've done it. Perhaps we could take that up on another thread to keep this one from becoming swamped with the Tastes Great / Less Filling debate.
  13. Where is this anchor roller sketch of what you speak, and can it be added to a CS17 mk 1?
  14. This is the same system I have on Rocinante (CS17). It's a matter of personal preference - I like to have the sheet coming from in front of me. It does clutter up the thwart, though.
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