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Jvodan

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Everything posted by Jvodan

  1. Cheers I don't think it cost much more to go down the composite route. The nidacore and fabric cost a little less than what the plywood would have. Though once the cost of extra resin and supplies used to fix the issues are added it was more expensive. The time involved even without the fixes was substantially higher, at a guess more than double. There was also a lot time spent waiting for epoxy to dry especially in winter when it was taking two days for the epoxy to harden enough to sand. It is definitely robust
  2. Slowly getting there. it took a fair bit of work to sort out the places where the panels buckled and bowed. I used 3mm closed cell foam to fill these. After I fixed the dips I covered the hull in a 80g/m cloth and fared it will a colloidal silica mix. The cloth was a bit on the sacrificial side and in a lot of places I sanded into it. My aim was to have the final layers of cloth follow the actual shape. Between the the stiffness of the panels joined at the butterfly join and the tension at the first bulkhead the nidacore buckled It also dipped along the keel line Then I added a keel pad to provide a flat section for the keel planks to sit. I filleted this with a microfibre mix and covered it in two layers of 400g/m bi axial tape. Without the keel pad there was no way I was going to get the keel on at right angles to the hull. The big section of layers of foam are fixing a dip where the hull warped when I glassed the inside. I only used two layers wood on the gunnels as between the 400gm biaxial tape on each side and the microfibre blend I injected into the top of the core I figured it was stiff enough. In addition the strips didn't sit flush against the hull, so I filled the void with a microfibre mix on the lower side. I have laid up two layers of 200g/m basalt twill cloth, I did this in three sections on each side overlapped over the keel pad. Because the Basalt cloth wets out black the epoxy has got a decent post cure bake. The next step is to attach the keel planks and fair. Would I use nidacore on a stitch n glue build again? Hell no! Well maybe after laying up 2oz cloth before stitching. What ever the case I would buy the full size plans. I suspect quite a few of my issues arise from my poor lofting skils Is it under weight? I doubt it, based on materials used probably 40 to 45kg. I will weigh it after cutting it in two.
  3. Meet Asym! Why Asym? Well it's not Symetrical, the nesting bulkhead is slightly rotated and the sunnier side warped as the epoxy set, so the transom is about 8mm higher on one side. The extra plywood squares on the transom are backing plates for Razza folding wheels. I am beefing up the transom to hull join to deal with the potential stress with thick fillets and taping twice with 400gr/m biaxial tape. I clamped one layer of the gunnels to the sides when I glassed the interior. I glassed up to the clamps and have since put a layer of 400gr/m bi-axial tape inside and outside along the top edge. Next step is to fit the aft seats to form the shape of the sides and flatten a warp on the port bottom. Then glue the gunnels on (in 3 layers), trim the sides to the gunnels and fill the core along the top edges, before attaching the foredeck. That will complete the interior with the exception of the center board trunk. I am looking forward to seeing the bottom which I expect to take a lot less time to reach the fairing point. At this stage my plan after shaping and taping the joins is to lay lite cloth first as it can be tricky to get the hexacore to wet out and then apply a single layer of 200 gr/m basalt cloth. There are a couple of dents around the forward bulkheads I will patch these with 300gr/m cloth and then fill and fair out before the layer of lite cloth The aft was extended 6cm because I placed the nesting bulkhead too far aft by 1cm, meaning it was not going to nest. I choose to extend by 6cm because that was the bite length of my clamps. I felt adding only 2cm would be more difficult. I actually doubt it will nest or nest completely because of the slight twist in the bulkhead. oh well it's a 8SNe semi nesting extended. I must admit that this project was rather ambitious for my skill level. This is my first stitch and glue and my fibre glass experience prior was limited to a composite mast step for my plastic sailing kayak. In getting this far I have probably done more 'carpentry' than I have done in the last 20 years. I definitely underestimated the amount of work involved especially on how much more work going composite would add. Despite the beefier transom and my beginners tendency to over engineer, the hull feels very lite.
  4. I laminated the seats first and found the hexcore warped when just glassed on one side
  5. Progress update. Weather has not been great. It has rained 6 out of 7 days since Christmas however I am far enough into the 3D stage to have some opinions about what I would do differently if I was starting from scratch. Use Plywood. The lack of stiffness means getting the shape is really difficult. The panels curve at the bulk heads but the curve does not extend very far. Despite wiring the bottom panels to the cradles my boat is going to have a much more of a flat bottom than the design. The lack of curvature has thrown the shear line off (top of the gunwales) If I still insisted on using hexagon core I would either pre laminate both sides with lite cloth and or use a female mold for the base. Since taping the seams rain has on several occasions filled the sections and deformed the shape, The cradles deformed the bottom when the hull filled with water. I am about one dry weekend from turning it over to glass the bottom. The weather forecast is for 7 days rain. I also wouldn't repeat the mistake of having a butt join forward (sheets came as 1.2m x 1.2m) I would buy the full size plans as my lofting skills seem to leave alot to be desired. I have bought a sail with the plan number on it, my boat will be so off spec they may wish I remove the number and not call in a spindrift 9. ? I might still come under weight though I suspect I may blow alot of my savings on fairing compound
  6. Brief update Sail and hardware arrived today from the USA, however I am still waiting on the timber for the gunwales and transom stiffener, etc. I ordered these locally in Australia at the same time. Australia tends to go on 'holiday' from Xmas till mid January. Annoying because I am a couple of hours away from being ready to go 3D. Revision on projected weight after building some larger panels (seat panels and transom). It will most likely be slightly over weight but under the weight of a hoop pine version. Hoop pine is the local marine ply. Gabbon /Oakhume is available here as an import but the BS standard is meaningless here and unenforceable. So there is no real guarantee of what you are actually getting. Hoop pine is about 30% heavier.
  7. Inspired by Sailing Florence (youtube) and William (https://messing-about.com/forums/profile/2082-william/ ) I have started a build of a Spindrift 9N using the local equivalent of 6 mm nida core. I refer to it as nida core but I suspect it is somewhat different. From the marketing blurb "The core has 3 orientations vs the 2 orientations common with other honeycomb panels," Unlike others who have taken this approach I am not planning on using any carbon. I plan to use 2 layers of 200g/m basalt trill for the exterior hull and a single layer 300g/m biaxial for the interior. 300g/m is about 10oz cloth 200g/m about 7oz I will be making the nesting bulkheads out of 6.5mm (1/4") marine plywood as per the plans. The transom is to be from honeycomb core covered in 300gm biaxial capped on the exterior by 6.5mm(1/4") plywood that is 6mm oversize to cap the thicken epoxy filling of the end cores of the hull sections. The transom stiffener and outboard pad with be as per plans. There will also be plywood pads on the interior of the transom to support bolting on folding wheel mounts, I will dig out the core where these pads will sit and replace with thicken epoxy. I chose honeycomb core for weight savings as I wish to keep the weight down so I can easy lift each section onto my roof racks. The choice of basalt cloth was for abrasion resistance as my locale has alot of rock oysters. Basalt is almost as good as kevlar but cheaper and easier to work with (or so I am told). Due to the risk of oysters I was always going to have to sheath the bottom. so I was never going to get to design weight unless I chose a lighter weight hull material. My experiments reveal honeycomb core with layer of 300g/m on both sides is less than half the weight of the available 6.5mm bare marine ply (hoop pine). I am using peel ply to keep the weight down* and to reduce the amount of sanding. *less excess epoxy. I have found in testing, once each side has a layer of 300g/m biaxial cloth it's much pretty inflexible, definitely less than 6.5mm hoop pine ply so I am not going to sheath the hull sections until wired together. Progress is slow on account of the weather (wet summer here). The honeycomb core arrived in 1200x1200mm sections so there are more butt joints. In addition I ripped the honeycomb core into 650 and 550 wide strips as I have limited covered space. so double the number of butt joins. I bought slow harder as I expected hot weather :-( I will post photos and add to this thread once I have got to the interesting stages. I am finding the honeycomb core easy to cut to shape and the 6mm local equivalent is not crushing when cut as William's did, though his was thinner. I am following his steps in not sheathing the hull sections until wired together. James
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