mustangermatt

The boat looks great! I like the cradle you built. I am glad I am finally doing the decks so I am not bending over so far on my too low cradle :-) Don't forget before you glue the after bulkhead that you will have to put the keel batten under it. Otherwise you will end up putting it in in two pieces like I did :-)

One place I would look closely at before gluing is to make sure the curve is fair along the keel and bottom in the area where the 1/4" bottom pieces join the 3/8" pieces. I found on mine this is where the "pooch" showed before I adjusted the edges of the midship keel joint area. But it sounds like you have probably already done that :-)

I chose the coresound 17 because of its speed and simplicity of build. I need a pretty fast boat to keep the time between campsites to a minimum for the kids :-) I also needed something that could safely make 25 - 30 mile passages (like across the Strait of Juan de Fuca or Straight of Georgia) on occasion. I actually like the looks of some of the other boats I was considering better, but the functionality and performance of the coresound are hard to beat. As for the simplicity of build, I really don't think there is a huge amount of difference between the coresound and say welsfords designs. For the coresound you need to pick up some epoxy/fiberglass skills, and I hear the glued lap boats are heavier on wood skills. I was expecting to finish my 17 in 4-5 months, it has been 10 and I am just finishing the deck frames. To build any boat right is going to take time and effort, so I won't use building ease as the primary criteria for the next one. None of the boats worth building are "easy", but I find that as mine nears completion I am going to miss the build time. Maybe I will need a second boat... Also, don't let the guys on this forum bully you into the CS 20 over the 17. Topic for a different thread but it all has to do with Frued and his theories on the male fixation with size :-) Now I'm in trouble :wink: It sounds like you are looking at some of the best designers so you really can't go wrong whatever you choose.

Something else to consider in choosing fir is that it has three plys in 1/4" compared to five in the okuome. On my coresound that has required a bunch of extra framing due to the lack of rigidity in the direction of the single ply. Especially on deck and seat areas that are required to bear the full weight of an adult. My primary reason for choosing doug fir marine ply was that it was the only way I could be sure I was using a truly renewable and managed resource as apposed to the imported woods that may or may not be harvested in a responsible manner. And its cool to know my boat is built of entirely local species too, not that I am proud of the northwests timber traditions or anything :-)

Sorry to hear about your trouble. I think the wood insert will go a long way to avoid another incident like this. Looking at the photos it appears that the compression side of the tube failed, not the tension side. By putting a "core" in there it will force the tension side to let go at the same time or before the compression side.

I have never sailed a weekender, but on larger traditional boats I have sailed backwinding the jib usually does the trick as well. Ease the jib (stay sail if its a cutter) as you ease off the wind keeping the main hard in. As you come around into the wind the main will be pushing the stern downwind while the eased headsail sheets allow the bow to come up. As the bow comes into the wind haul the sheets back in (don't switch sides yet) and the backwinded headsails will pull the bow right around. Once the main begins to draw you let the headsail/s come across and sheet them home, and off you go. Finally, nothing against the weekender but remember that the gaff sail and full keel are a terrible combination to windward. Be sure not to pinch the wind too much since this will "stall" that board your dragging around below causing huge drag. This in turn results in decreased steerageway and increased leeway, which on most boats more than negates any gain you might have gotten from pointing closer to your intended heading. Hope this helps

Just so you feel better, I had to tack 4 inches back onto each side piece at the stern, and those measurements were on the wood for more than a day :oops: Scott is right though. Since then I spend much more time thinking about the next step than actually doing it. I make alot more progress that way :-)

My hull had a slight dip just aft of the forward bulkhead while stitching. I found that it was caused by the bevel on the mating bottom pieces was not quite true. Once this was corrected there was no tendancy to dip with my suports that only go about two thirds of the way out. I think the difference may be the doug fir ply. It is not as stiff as the okoume across the grain (so decks and seats have required a little extra framing) but boy is it rigid along the grain!

I am not a weekender sailor but in general you will want a sail to be rather full bellied for light air and much flatter when wind speed is higher. Your sail is an air foil and as the air speed increases it generates lift destroying turbulance as it tries to make too sharp a turn. On the other hand a sail that is too flat in light air doesn't make the air turn sharp enough to create the vacuum that equals lift. The short answer is make the thing adjustable if you can :-)

I let the fillets harden and then sanded them prior to taping. I think it is a matter of personal opinion, but I would rather sand with 60 grit than be a slave to the epoxy curing time :-) Most of my fillets wound up needing very little fairing anyway. Just lucky I guess. However your doing it, looks great!

The Groote Beer (dutch for Great Bear) that I sailed on as a sea scout was a large dutch leeboard cutter. If sailed correctly her performance was suprising. One annoying tendancy of leeboards is that they sometimes float out away from the side of the boat in light air, then bang back in on the next swell. As far as using them on a coresound my first question would be what would you really gain? Don't get me wrong, I probably like leeboards better than most, but the coresound has a very good system already which is easier to build. Remember that one of the areas of highest stress on a boat will be around the keel/centerbaord/leeboard. With a centerboard you only have to build the supporting structure once instead of twice. If you do end up using leeboards look at a dutch "botter" first. There are a few sites with them on the web. These where the height of the commercial leeboard vessels. You will notice that the leeboards are high aspect ratio (long) not the ridiculous fan shaped things you see on most american copies (sea pearls for instance) :-). And then get the offsets for a naca foil and loft your boards to that. A flat leeboard (or centerboard or keel) is in a constant stall with turbulance on the windward side where the lift is supposed to be coming from. Very inefficient. Fore a fast boat like the coresound you owe it to yourself to at least use the technology the Dutch shipbuilders used 100 years ago :-)

I sailed on a larger (65') traditional gaff cutter for several years as a teenager. A few things we did to deal with running... 1. A preventer line from the boom leading down and slightly forward to keep the boom from lifting up. That eliminated the most common cause of an uncontrolled jibe. 2. We often sailed on a broad reach rather than run since the boat was faster on that point of sail with both heads'ls filled, in affect "tacking" downwind. The shortest distance between two points is not always a straight line :-) 3. When jibing we put the wind a little more on the windward quarter first, eased the preventer at the same time we hauled the main sheet in all the way, then eased the boat around controlling the jibe with the helm. 4. In anything more than a light breeze we would round up into the wind and tack rather than jibe.

Building a cradle is way less work than trying to get things right without one. There have been some of the core sounds built with a pronounced sag even in cradles if the center isn't supported. We wired the two halves together at the keel on the floor, lifted them onto the cradle and unfolded. We then did the rest of the wiring on the cradle. Another advantage I didn't foresee was that the solid midship bunk kept the bottom sheet all lined up after I cut the centerboard slot so I could glue in the trunk without worrying if the bottom had deformed. It is also nice to be able to level the cradle and boat, so I can use a bubble level to set up mast rake, seat framing etc. Finally, the castors on my cradle have made it possible to compfortably build the cs 17 in a workspace 17 x 10.

When I was experimenting with frame spacing for my seats (doug fir marine 3 ply on tops = less longitudinal rigidity than 5 ply okoume, thus a few extra frames) I played around with Hemlock (equivalent of dept store white pine from the PNW), Doug Fir, Western Red Cedar, and Poplar for the frames. Only the Poplar and Doug Fir where rigid enough to really add anything to the seat stiffness. I went with doug fir for the lighter weight and used poplar bright finished where it shows (laminated deck frame in cockpit etc). I have used some Hemlock in my boat for things like the hatch lid frames where strength is not a real concern, and these parts are well sealed with epoxy paint over the epoxy coating. Time will tell if this was a bad idea or not, but clear doug fir is hard to find sometimes :-(

I think the big difference in a jibe for sprit and boom sails is that the sprit sail has a constant downward pressure on the clew (aft lower corner) applied by the angle of the sprit. On the traditional boom there is nothing but the sheet to hold it down. As the sheet is eased going down wind the angle of the sheet changes and now there is nothing but gravity holding the boom down. Wind pressure from astern twists the leach (back edge) of the sail forward and lifting the boom. As the boom lifts the sheet that was flat now forces the boom to arc inward as it goes up, sometimes far enough that the wind from astern will start to fill the sail from the "back" side. Now the boom swings to the other side, and the sail with it, with a banging crash when the sheet comes tight on the other side. This is often when the capsize occurs on smaller boats. I have never done a "scientific analysis" of this, but I think that more than the weight of the boom it is the weight of the air mass trapped in the sail that causes such havoc. In a controlled jibe the mainsheet is taken all the way in reducing the amount of travel on the sail as it goes over. On larger boats like gaff schooners you will often see them avoid a jibe at all (controlled or uncontrolled) by wearing all the way around into the wind and actually tacking, then they fall off onto the new reach. Sorry to get so wordy on this, the topic just brought back some fond memories of 470's when I was young :-)

Ok, I have to throw in my pitch for the CS 17 since nobody else is :-) I have never righted either boat, and I am just decking my 17 now so take my input for what it is worth. I am an experienced sailor however on both large and small boats... First off the hull weight of the 20 is considerably greater than the 17 (30%). I am guessing that this will make the 20 more difficult to right, but it is only a guess and I have no idea how much difference. I have a software mock up of the 17 that gives predicted righting moments etc for different angles of heel. If I get time I will do the same for the 20 and compare them. The most common reasons people give for choosing the 20 over the 17 that I have read are room and carrying capacity. There is no doubt the 20 has more room, the cockpit is a couple feet longer and almost a foot wider. I have had my family of 6 in our 17 on the cradle. We seem to fit fine with lots of extra room, but then we all like each other and that might change after 4 or 5 hours becalmed :-) It is important to note that the designed carrying capacity or "payload" for both boats is the same (600 lbs) because of the 20's heavier hull. So you get more room but you can't put any more weight in it (I am just going by Grahams numbers here). I like both boats alot, but in my case less is better for the use we plan. Either way I don't think you can go wrong.

My brother is a desk manager at large car dealership, and always says if someone is happy with the price they got it was a fair deal. The main thing is you got enough to finish your boat. We are getting ready to make those last big expenditures as well and it is a good feeling to know you have the money. Congratulations

Very good point about the size. Steel in a small boat will wind up being quite a bit heavier than plywood. Once you move into the larger boats and ships this is no longer true. One reason aluminium would not be my first choice for a larger boat is work hardening causing cracks. This is especially true in areas of the hull that experience vibration such as hull plating above a high speed screw, or around the rudder post.

Think that flipping the axle thing through carefully. I owned a camp trailer that had the axle on top of the spring. I don't know if that was the design or not, but when the U bolt broke, wow. The axle (and wheel) on the right side went up and back three feet destroying everything in its path. Inner fender, flooring, coat closet and entry door all splinters. Not to mention the trailer was stuck in the middle of the highway. There are many cars, trucks, and trailers designed to have the axle on top, just be sure you know what loads your dealing with and that the hardware can take it.

I agree that having weight aft will probably take the boat out of it's best trim in some conditions, but just because you have a seat back there doesn't mean you have to sit in it if your trying to go fast. Also no aft deck will make mounting an outboard easier. I also agree with the access to the rudder issue, but what are teenagers for if not to clear the old mans rudder when he runs over a crab trap :-) I am decking mine because I need the stowage for camping, I don't plan on an outboard (though I will reinforce the transom for a bolt on mount if it makes sense later), I like the extra flotation in case something bad happens, there is plenty of room for my family even with the deck, the kids like laying/sitting on decks, and I personally think the boat has a more genteel look with the deck. Not that the open transom is unattractive, it's simply a little more practical looking. Since this is my "yacht" I want it to be practical, but not look it :-) That is pretty much why I chose to deck mine, we will see how it works out after launching. Bruce, congrats on your launching!

There have been a lot of good points made on the previous posts both ways. But for me it came down to my shop is 17' 4" long :-)

Actually I am decking the aft section. My shop is just to short to get the whole boat in the picture :-) I figured if I wanted to sit back there, on the deck would be good and I need the storage to take the whole family camping.

Sorry about the cheap camera, I am spending money on epoxy and glass instead of electronics right now :-) A little more work on the interior, then I get to start framing the deck! I am starting to view things by whats left to do rather than what I have gotten done. I guess that means I am seeing light at the end of the tunnel. [/img] [attachment over 4 years old deleted by admin]

Scott, I was going to take some pictures last night but my son had scavanged the batteries out of the camera for his rc car. Thats the downside of having kids, the upside is that I can make progress on the boat because they do alot of work on it :-) I am still going to be 6 months behind what I expected by the time I launch. Oh well, the journey and all that :-) I am going to get some batteries today, hopefully I will get the pictures up tonight.

Looks like we posted at the same time. Glad to hear you went with the better wood, I think you'll be very happy you did as you get further along. I am about 3/4 done with my cs 17 (#97), started last september and I expect to launch September or October this year. I have decking, hull glass, paint and rigging to complete. It is taking longer than I originally expected but I guess I don't have as much time to work on it as I thought :-) It is turning out to be a very nice boat though, I am really happy with the design. I had considered some of the other flat bottom designs, but this one is much prettier.