wardm

Hi Peter Thanks for the photos, we actually sailed past each other off the sw corner of Peel Is yesterday, we were competing in the Great Bay Race in our Azuli F40 Catamaran. I was excited to see your Core Sound sailing, she looks nice. I built a S10 a couple of years ago, and use it as a tender as well as a camping dinghy. I would have liked to pull into horseshoe bay yesterday to have a closer inpsection of your boat, but had to complete our race... Hopefully one day I will get the opportunity to see your boat up close as I am thinking of building one once my boat sells. Where did you launch from ? Cheers Mark

Another option that is much less work than painting, less costly, and lasts very well is to use Tectlyl 151 it is a Valvoline product that useally comes in a spray pack. It is not as hard wearing as Anodise, but for the home build it is a cheap, quick and effective option for masts, booms, etc. I usually clean the aluminium fist with an Acid wash, then coat with Tectyl 151 Tectyl is used by mast builders and tinny (aluminium dinghy) makers in Australia. Can also be applied with a rag. Do multiple coats to get a good thickness, it dries clear and retains the shiny look from the acid wash. Further down the track if wanting to re apply it is recoatable into itself.

Thanks Rob I think I will take your advice and go with the CS 20. I have not seen a CS in the flesh yet, so may take you up on the offer. I used to windsurf Lennox and Flatrock years ago, very nice place. Cheers Mark

Very Nice Rob, Thanks for sharing Is that a CS17 or CS20 ? I'm currently trying to decide between 17 or 20 ft Core Sound design to build for sailing Moreton Bay, and other Queensland esturaries. Cheers Mark

Andre You could try http://www.onlinemetals.com. shipping might be expensive though. I think a Laser sailing dinghy mast top section and boom match the required dimensions and are also 6061 T6, if you could find an old section lying around it might do the job for the bottom half of the S10 mast. I had a lot of old sailboard mast sections lying around from my windsurfing days, but they were all a little shorter than the S10 required mast length, so I used a Fibrespar carbon sailboard mast top section and alloy tube bottom section for my S10. Good luck Mark

Hi Andre I am not sure if you saw these threads. I had trouble with a weak tube section on my S10 as I could not get 6061 either, you can see the pictures of what happened at the bottom of this thread. I could not get 6061 T6, but am now using 6063 T6 with a stiffener in the bottom section. So far so good http://www.messing-about.com/forums/index.php?topic=5760.0 There is also some good information on this thread. http://www.messing-about.com/forums/index.php?topic=2015.0 Some of the interesting points from postings on this thread - The two alloys are fairly comparable. 6061 is optimized for strength, where 6063 is optimized for corrosion resistance and formability. The yield strengths are like 40,000 psi vs. 32,000 psi. - The 2 1/4" od x.065" wall 6061 T6 is just strong enough for your boat. As 6063 probably T5 is a lot weaker, then your only option is to use the heavier 2" id x 3mm wall if you can't get the right stuff. For the next section you can get whatever will fit inside the lower section and you can make a wood top piece. Wikipedia also has information to explain the difference between the two alloys and the different tempers http://en.wikipedia.org/wiki/6061_aluminum http://en.wikipedia.org/wiki/6063_aluminum Rgds Mark

Peter Thanks for sharing the pictures of your boat, it's looking great. Nice to know there are a couple of these boats in the area. It will be great to see them on the water. Cheers Mark

I was wondering if there might be any B&B boats at this regatta in Bribie Island (Australia) on 24/25 May. I am particularly interested in seeing a Core Sound or Bay River Skiff up close?

Here's what I used for my SD10 built on Australia, I expect the professional US builders may have additional advice. >>where the mainsheet block attaches on the bottom (a couple bolts throught the keel and plywood) I used thickened epoxy resin, same mixture a used for filleting the sheet joints >>bolting the pintles to the transom same as above >>attaching a self-bailer (with a gasket, too) Sikaflex

Hi Guys Thanks for replying and sharing your thoughts and experience of the Core Sound. Planing in 12 knots of wind sounds pretty good. Also achieving ~9 knots boat speed in 11-12 knots of wind. I notice the pictures of the CS17 on the B&B site that it appears to have battenless sails without any roach. Where as the EC 22 appears to have more powerful sails with more roach and battens. I am wondering if the CS17 was rigged with sails similar in design to that illustrated for the EC22 would it perform even better.

I am considering building a Core Sound 17 and would like to learn more about the sailing performance that can be achieved from this design. I have searched the forum threads, and while there are plenty of comments about their great performance, I cannot find any numbers quoting the achievable boatspeed. Has anyone produced a table of boatspeed vs windspeed vs sailing angles like those polar diagrams that some yachts manufacturers produce? How would it compare in performance to the trusty old TS16 (http://www.duckworksmagazine.com/04/s/vintage/sbj/018/index.cfm) Would the Coresound match the performance quoted on this page for the TS16 ? "[Planing,] this boat can reach speeds of 12 to 14 knots on reaches and runs, often out performing boats up to 24 feet. With two crew swinging their weight outboard, you should plane on a broad reach in about 15 knots of wind." I am looking for a versatile design that I can use in bays and rivers for camping and fishing with the family, but I don't want to build a slow boat. The TS16 is now a 30yr old design, and I would like to build something a little more modern that is fast and versatile.

Another option for aluminium masts/booms is Tectyl 151 - this product, when applied on aluminium, forms a clear film that protects it from corrosion. I used on my Spindrift and on my Azuli F40 cat's 50 foot wing mast. I found it needs to be recoated on high wear areas after a few years, but holds up pretty good. It can be applied by cloth, brush or spray.

I made the hole in the collar a bit larger then applied a couple of wraps of epoxy and tape around the aluminium tube at the point where the collar touches the mast to protect the tube from wear. I noticed that if the fit is too tight it can be difficult to pull the mast out when derigging. So I sanded the epoxy tape back a bit to give a couple of millimeter slop so I can wriggle the mast out.

Graham Thanks for your reply and for running the calcs on my new tube specs. My wife took the picture at the right time just after a good gust of wind that caused the mast to start bending. I like your suggestions to strengthen the critical area of the mast with an X shape wooden plug. I was thinking of making the plug by laminating 2 layers of 6mm gaboon ply and then interleaving the sections to make the X shape, then filleting the joins with the same epoxy filler used for the boat, and coating the whole plug with epoxy resin. Does this method sound OK? Alternatively, I have some 19mm Douglas Fir that I could use to make the plug? Mark

Thanks again Peter, I have tracked down some 50mm x 2mm 6061 T6 in Sydney. It seems the local yacht riggers don't carry this stuff. As you predicted, the freight costs for a 3m length is nearly as much as the tube. Your CS17 looks great, you are doing great job. Thanks also PinoyPiper for your information, that's another option if I get really stuck. Cheers Mark