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Thread: Kotik, Kotik, Kotik!

  1. #246
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    Default Re: Kotik, Kotik, Kotik!

    Here is the current state of the play. The interior still looks like this:


    After assembling the centreboard, I shaped the sides on the bench, then propped it up to shape the edges. It weighs about 40kg.


    I coated the board with epoxy, one side at a time, and rigged a tent to help the resin set in this frosty weather. It was set enough to turn over after a couple of hours. Then I did the same with fairing filler. I took this photo this morning, before I took the tent apart.


    Then I sanded both sides flat with my belt sander. It needs a bit more fairing yet.


    I picked up the rudder fittings and chain plates from the foundry today. They are cast from aluminium bronze (AB2) which looks more yellow than silicon bronze. I asked for them not to be polished smooth and shiny. I will scrub them up a bit with a flap-disc on my angle grinder, and paint them.


    When I was making the patterns I drilled the holes in the gudgeons and assembled the parts on the sternpost, for a sneak preview. Then I filled in the holes again. The sternpost will have to be shaped a little more to fit the castings.


    I have to tear myself away from the boatbuilding for a few weeks now, but don't worry, I'll be back!
    Cheers,
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  2. #247
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    Default Re: Kotik, Kotik, Kotik!

    Nice castings Ian. I confess i only like bronze once its gone green......a certain J class yacht put me off polishing bronze, its a bit like varnish.....you can have too much of it.......id rather be sailing.

  3. #248
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    Default Re: Kotik, Kotik, Kotik!

    Have a good break Ian, you've been working pretty hard. Looks good.

  4. #249
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    Default Re: Kotik, Kotik, Kotik!

    Thanks, Ian and Andrew.
    I'm not a great fan for maintaining lots of bright shiny stuff either. I think the brightwork will be either Deks Olje or Sikkens Cetol, when I get that far.
    Right now, it will be good to have a break.
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  5. #250
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    Default Re: Kotik, Kotik, Kotik!

    Well, we had a good break, thanks. We've been back for a couple of weeks but there have been a few things to catch up on, as is to be expected. I have been fiddling around a bit with the centreboard and it's nearly ready to paint, so it will be good to get that out of the way. Then the plan is to fillet the laps and fill the gaps under the frames, then fibreglass the inside of the planking, then fillet the frames to the planking. As I've said before, fibreglassing is not a normal part of the glued clinker method or Iain's specifications, but I'm just doing it because I couldn't get the 7-ply I wanted.
    I have been writing a report on our trip, which I am putting on the People and Places section, called "Raid Pomerania 2017". It was a very good trip.
    Cheers,
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  6. #251
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    Default Re: Kotik, Kotik, Kotik!

    Last week I was figuring out how to sling up the centreboard and lower it into the case, so I've got a good enough system now. The board is too heavy at 45kg (100 lb) just to pick it up and drop it in. These photos were taken on different days, but show the effect.

    Here is the board slung up at its balance point, by a thin webbing strap, using a 3-part tackle hooked onto a line stretched along the overhead beam, so I can drag it across to above the c/case.


    Here's how it ends up underneath. (I filled in the pivot hole and redrilled it about 9mm (3/8") nearer the top of the board to give it a bit more
    clearance at the front. The bearing is epoxy with high density filler.


    And this is the top view.


    I put a couple of layers of fibreglass tape around the bottom corner.


    The temperature is usually 4 - 8 degrees Celsius (40 - 50 F) in the workshop these days, so I'm using fan heaters where I can.


    This is the first coat of primer/undercoat. The second coat went on today. Three coats of antifouling to go.


    Between coats of paint, I am marking a line around the inside of the hull, 45mm (1 3/4 ") below the top of the centreboard case, to locate the bunk-top framing. The lines will show up better on the bare wood than on fibreglass.

    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  7. #252
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    Default Re: Kotik, Kotik, Kotik!

    The boat is looking fine. I, too, am intrigued by that centerboard arrangement. Hard for the pivot hole to leak if it's outside the boat!
    I was born on a wooden boat that I built myself.

  8. #253
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    Default Re: Kotik, Kotik, Kotik!

    Thanks, Rich.
    Progress has been in fits and starts lately, with plenty of interruptions.
    Here's a shot of the centreboard, which was meant to be the final installation, but I think I'm going to pull it out again and move the pivot hole to have the board sitting a bit higher in the case. There is enough room in the top of the case.


    I carefully levelled the boat, using the top of the case as a reference. Then I marked a position 45mm (1 3/4") above the waterline on each of the mould patterns I had made from the lofting, and used them to mark that point at each station line.


    Then I used my cheapo laser to connect the dots, right around the boat. The line marks the top of the bunk framing.


    The laser's tripod was too tall for this job, so my wife let me use this clever device from her collection.


    It's all made out of one piece. Amazing!


    After filling all the gaps under the frames and filleting the seams, I hand-sanded the whole hull with 60 grit paper. Then I made newspaper patterns for the pieces of 10 oz. woven rovings I am going to fibreglass the bottom with, up to the bunk framing line. (The pencil line is a bit faint. I inked it in later.) The 'glass won't follow the kinks of the plank seams very well, so I'll just cut it where I have to. The same patterns fit both sides, and I'll do one side at a time. Above the line I'll use the same 6 oz. cloth I used for the outside of the planks.


    Until next time...

    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  9. #254
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    Default Re: Kotik, Kotik, Kotik!

    OK. This is next time. The spring weather here has been quite nice lately so I have got some fibreglassing done.

    First I made wider fillets along the bottom seams with the curved edge of my putty knife, hoping that the woven rovings would fit into them without my having to cut them at the laps. They did! I cut out the panels of rovings for the bottom of the boat and put them in place, then made newspaper patterns for the sides by resting the lower edge of the paper on the top edge of the rovings. When I cut out the 'glass pieces for the sides I allowed for an inch (25mm) overlap.



    Then I epoxied the bottom panels of the port side while kneeling on the starboard side, and did the starboard side two days later. I gave each side of the bottom three coats of resin on the same day, which took a bit of organising. After each stage I rigged a centre-line between the stems and put some tarpaulins over it to cover the boat, with a couple of these heaters running for a while. I am not going to paint the bottom (bilges). I would rather be able to see what's there.


    Here's the bottom, done. I will go over it to get rid of any spiky bits, but this is how it will look.


    Here I have glassed the starboard topside, and hung up the panels for the port side. It took me four hours to epoxy the first four panels, with a brush, working my way carefully down from the sheer, plank by plank. I didn't have to cut any of these at the laps either. After lunch I gave them a second coat of resin, then epoxied the stern section, which is made up of large scraps. The joints were quite fiddly. I gave this a second coat in the evening. I decided that two coats were sufficient for the topsides as the plywood was well covered.


    And here are a couple of general views of the interior, looking towards the stern,


    and towards the bow. The first four panels above the bunks will form the cabin sides, so they will be sanded and painted. The panels aft of the cabin bulkhead will be covered by the cockpit and after deck, so they will be left plain.


    I am looking forward to seeing some of you at Port Townsend.
    Cheers,
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  10. #255
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    Default Re: Kotik, Kotik, Kotik!

    Very courageous effort Ian. Did you know it was going to work? If I'd have seen this before doing my boat I might have at least done the outside. Gaboon ply is easily dinged!!
    Have a good trip.

  11. #256
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    Default Re: Kotik, Kotik, Kotik!

    Hi Ian,

    That looks great. And, pretty smart to do all that fiberglass work before the deck goes on.
    Hope to see you Saturday.

    Travis.

  12. #257
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    Default Re: Kotik, Kotik, Kotik!

    Thanks, Andrew. Good to hear from you. I thought it would work, or I could make it work. There are some interesting threads on this forum about fibreglassing lapstrake, including yours. The glass on the outside improves the abrasion resistance, and the glass on the inside improves the tensile strength. I'm happy enough with my hull now.
    The Kotik is almost as big as the Grey Seal, and your plywood is thicker, so you should be fine.

    Thanks, Travis. I would hate to be trying to do it with the deck on. I will be building as much of the interior as possible before I even start the deck framing.
    I tried to send you a PM the other day, but it didn't seem to work. You can camp at the Jefferson Fairground without having to book a site. We will be doing that.

    Ian

  13. #258
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    Default Re: Kotik, Kotik, Kotik!

    Ian,

    I tried to PM you a couple times - it doesn't seem to be working. Your message came through ok. If I could get it working, I'd send you my cell number.
    There's a chance I might come up Friday evening and stay at Jefferson Fairground. I'm at least planning on going to the PTWBF on Saturday.
    Hope to see you there. I'll keep an eye out for you.

    Travis.

  14. #259
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    Default Re: Kotik, Kotik, Kotik!

    Hi Travis,
    I just got your PM, thanks, and replied. I think it worked. We are at PT now.
    Ian

  15. #260
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    Default Re: Kotik, Kotik, Kotik!

    We enjoyed the Port Townsend Wooden Boat Festival very much, meeting some of you and some of you again, and got home on 20th September after visiting my niece in California the following weekend. Since then, I have sanded the inside of the hull, which took about five days, using my random orbital sander, 60 grit, hand sandpaper, also 60 grit, and coarse steel wool, accompanied by classical music on the radio. Well, you get through it.


    Then I put the centreboard back in, with its permanent winch cable installed. I had shifted the pivot hole, so the board sits higher in the case than it did before. The bolt is stainless steel (316) so I will pull it out after its first season in use and check it for corrosion against the copper-based anti-fouling.

    We had fun making a mock-up of the galley out of all sorts of bits and pieces. The idea is to sit on the c/case (port side), with the galley enclosed in cupboards on the starboard side, with doors hinged along the bottom to drop down and form the working surfaces. The c/case could just as easily have been built on the starboard side with the
    whole thing the other way around.


    In the last week I have made patterns for all the bulkheads, using the moulds and adding small pieces to the sides of the two biggest ones to get a neater fit down the sides, and drawing all the framing pieces on them. Two spare sheets of 3mm MDF came in handy for stations 4 and 6.
    At the companionway bulkhead I have brought the cockpit seats in closer together and raised the sole, to reduce the volume of the foot-well a little. The sole will slope aft instead of forward as in the plan, and I will drain it straight into the motor well, as I did in my Eun na Mara Islesburgh.


    The forward bulkhead will have an archway 2ft (600mm) wide, so the cabin should look fairly open.


    The patterns at stations 1 and 8 are the plywood moulds themselves.


    Well, back to work!
    Cheers,
    Ian
    Last edited by IanMilne; 10-08-2017 at 11:38 PM. Reason: typo
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  16. #261
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    Default Re: Kotik, Kotik, Kotik!

    You’re setting a cracking pace Ian. Well done. Bit curious about your cabin layout with the bulkhead at 4, you’re not worried about closing in too much? I assume your bunks are forward of 4 ?
    Top effort with the glass.

  17. #262
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    Default Re: Kotik, Kotik, Kotik!

    Wow, i would have definately considered doing the bilge area, but would be happy just to give all the ply above that 3 coats of pox, i would find the idea of 5 days sanding enough to put that off, and im too tight to pay someone else to do it! I clear coated the bottom in the planing sail boat, i should have done some more sanding, just sometimes i get a finger sliced on an epoxy barb when mopping out, my wrist/elbow stamina has been reduced by too much by the sanding process. More power to your elbow, looks great!

  18. #263
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    Default Re: Kotik, Kotik, Kotik!

    Thanks, Andrew and Ian. I'm happy enough with the hull now, so that's OK.
    The cracking pace goes in fits and starts. The average pace would be somewhat slower.
    We wondered if the "saloon" would feel a bit claustrophobic but the bulkhead at station 4 has a 600mm gap between the posts, so we think it will feel spacious enough. There will not be a central compression post. There will be a bunk (single or double) in the forward cabin and one quarter berth. We don't expect to sleep three but that will give some options.
    The layout will be adapted from the one shown in Iain's catalogue drawing. See message 32, page 1. I have the WB mags with GS Saturday Morning in them, too, showing different layouts.
    Today I drew around the bulkhead patterns onto the real plywood and cut out half of them.
    Ian
    Last edited by IanMilne; 10-27-2017 at 03:54 AM. Reason: typo
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  19. #264
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    Default Re: Kotik, Kotik, Kotik!

    I suppose you also have the advantage in having had a similar sized boat before as well so you can work out more easily what you want.
    I know what you mean about fits and starts, i had a fit once too often!!!

  20. #265
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    Default Re: Kotik, Kotik, Kotik!

    Quote Originally Posted by andrewpatrol View Post
    I suppose you also have the advantage in having had a similar sized boat before as well so you can work out more easily what you want.

    Yes, that helps work out the layout.

    Quote Originally Posted by andrewpatrol View Post
    I know what you mean about fits and starts, i had a fit once too often!!!
    Sorry, I didn't quite mean it that way. I hope you never have another.

    Hello again. Not much progress to report. We were away for a week, sailing Sooty Tern Trondra on a lake every day, then at a trailer-sailer event over our Labour Weekend (last weekend) on the same trip. There was not much wind until the last day, then there was too much, but it was a good week.

    We took the Kotik trailer back to its maker for some modifications before we went away, as we had always known we would. I'll get it back next week and glue the bulkheads into the hull after I have levelled it up again. It's just sitting on saw-stools at the moment, with the ends suspended from the ceiling beams. In the meantime I'll mill and fit the "lands" (32 x 20 mm) onto the bulkheads to support the lengthwise parts, and make the mizzen mast step.

    I'm going to build my Kotik as a yawl, with the mainmast in a tabernacle, but I will also build the mast step on the coach-roof for the sloop version so that it can be set up either way, in the manner of the Arctic/Sooty Tern plans which make the same provision. Thanks to Paul Grun at the Port Townsend WBF for showing me how the gunter rig works on his fine "Eel" canoe yawl Pickpocket.

    Here is a comment I put on Schwattwitt's thread "Grey Seal/Oughtread is she a fast Boat?" before I started this one:
    The WS/Kotik plans as received from Iain did not include a yawl rig for the Kotik or the 3-berth layout. I worked out a yawl rig for it from the proportions of the WS sloop and yawl rigs and the Kotik sloop rig, sent it to him and he tweaked it up for me. The mast is in a tabernacle attached to the front of the cabin. Iain also sent me a scale drawing of the 3-berth arrangement (as in the catalogue picture), a table of offsets for the planking lines, and a sketch of the construction needed to eliminate the central compression post. The extra length (about 18" (500mm)) of Kotik vs EM is really just in the rake of the ends. The waterline length is about the same.
    Apologies to schwattwitt. We are getting off your thread here a bit. I will start mine soon. Cheers, Ian
    (Iain's "tweaks" included making the sails bigger than I had drawn them.)

    Here is a photo of the interior of Andreas Sulzer's Kotik, built at the Boatbuilding Academy, Lyme Regis, England, from his blog "MyWay".
    http://myway22ft.blogspot.co.nz/



    That will do for now.
    Ian


    Last edited by IanMilne; 10-27-2017 at 05:59 AM. Reason: layout
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  21. #266
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    Default Re: Kotik, Kotik, Kotik!

    I'm getting a bit behind with my postings. We've been away several times lately, sailing Sooty Tern Trondra at some annual events we like to go to, so the Kotik-building has slowed down a bit. Trondra is a good boat!

    For the record, here is Kotik without trailer:


    and the fishes' eye view. I used a third cable-hoist from the middle beam to pull up the centreboard.


    Here are some photos of the trailer, with its modifications. Our trailer-maker very kindly brought it back to us, and did not charge extra for the changes. The wheels are further forward, there is a new crane to give more clearance between the stem and the winch, the "wobbly wheels" have been replaced by side-benches, and the guide-wheels have been rearranged to clear the off-centreboard and its outer support. The hull is much better supported now.




    Back in place, parallel with the bench. It's easy enough to "walk" the trailer into position if I take the back wheels off, and the brakes give good control on the sloping floor.


    Then I put the guide-posts back on the after end, took the other two wheels off and levelled her up.

    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  22. #267
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    Default Re: Kotik, Kotik, Kotik!

    I cut out the bulkheads as economically as possible from my other lot of plywood from a different supplier. This is 5-ply, but with thicker outer layers. Then I spread them out along the bench and gave them all two coats of epoxy, using 150mm (6") yellow foam rollers, both coats on the same day, one side one day, the other side the next day. On the third day I washed the amine blush off and sanded them all by hand with 80 grit paper and coarse steel wool. Maybe I could have got a smoother finish if I had put three coats on.



    Then I dry-fitted them all. This one is for a buoyancy compartment at station 1. It will have the samson post on it.


    Station 4, the forward cabin bulkhead. I made the posts on the router table.


    Cabin and cockpit bulkheads.


    Motor bulkhead. I will cut the opening for the motor-mounting after I get the motor.


    This is how it looks now.


    Since this photo was taken I have taken bulkhead 4 out and made and glued in reinforcing pieces along the insides of the sheer planks between the frames at stations 3 and 5, to take the chain-plates and a pair of beaching legs. Bulkhead 4 will have to be notched out for them. Today I installed the U-bolt in the stem for the trailer-winch and glued in the bulkhead at station 1.

    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  23. #268
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    Default Re: Kotik, Kotik, Kotik!

    Nice to find a trailer supplier willing to go that bit further, after a frenzied email exchange with a manufacturer in the UK who still has not answered my original questions regarding their product, its nice to see someone has still got good buisness practice.
    Nice job, carry on......

  24. #269
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    Default Re: Kotik, Kotik, Kotik!

    You’ve done plenty since last Ian, dunno how you fit holidays in. Will the bulkheads be filleted in?

  25. #270
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    Default Re: Kotik, Kotik, Kotik!

    Thanks, Ian and Andrew.

    It's really tough fitting in all these holidays. Well, there's only one more weekend away until January.

    Yes, there will be plenty of filleting to do after the bulkheads are glued in.

    I'm putting some Sooty Tern sailing photos on my "Southern Sooty Tern" thread.

    Cheers, Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  26. #271
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    Default Re: Kotik, Kotik, Kotik!

    I did see an interesting method to fit bulkheads recently. The bulkhead was fitted with a compressed silicone tubing between the plywood and the hull - noting but a good fit and friktion holding it into place. Then the fillets were made using thickened epoxy, one on either side of the tubing. After curing, the silicone tubing was removed by simply dragging it out at one side of the boat. This left a void at the centre of the bulkhead, between the fillets. The void was filled with neat epoxy - gravity flow from one side of the boat (e.g. starboard side of the boat). I hope you see what I mean... Probably a very strong way of fitting a bulkhead...

    /Fredrik

  27. #272
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    Default Re: Kotik, Kotik, Kotik!

    Quote Originally Posted by trango View Post
    I did see an interesting method to fit bulkheads recently. The bulkhead was fitted with a compressed silicone tubing between the plywood and the hull - noting but a good fit and friktion holding it into place. Then the fillets were made using thickened epoxy, one on either side of the tubing. After curing, the silicone tubing was removed by simply dragging it out at one side of the boat. This left a void at the centre of the bulkhead, between the fillets. The void was filled with neat epoxy - gravity flow from one side of the boat (e.g. starboard side of the boat). I hope you see what I mean... Probably a very strong way of fitting a bulkhead...

    /Fredrik
    Thats interesting, but what with the gap filling properties of epoxy anyway, seems like one might spend some time shaping the bulkhead so that its a good fit on the silicone tube, when a couple of small wood blocks either side would hold it in place while "tabs" were done. I guess if you want to do the whole thing in one go, both sides, its one way of doing it.....i usually use brass pins through the hull into the bulkhead edges if im doing both sides at once. Even a ratchet strap across the top of the bulkhead or fixed to extensions, can keep a bulkhead in situ while its bogged. The neat epoxy down the hole sound good, but neat resin is often brittle, and its good practice to have a few soaker-coats on end grain frames before fitting anyway to prevent resin being sucked out of a fillet mix.

  28. #273
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    Default Re: Kotik, Kotik, Kotik!

    Thanks for those ideas, Fredrik and Ian. I think the silicon tubing method is a bit too complicated for me. To glue in the bulkhead at stn 1, I brushed unthickened resin around the edges of the plywood, then thickened it and dabbed it on the marked position around the inside of the hull and around the edges of the plywood again, so as to leave small peaks and points of glue, then put the bulkhead in its place, supported by small blocks clamped to the sheer and a piece of wood propped against the floor at stn 2, smoothed up the glue with my finger (I wear blue nitrile gloves) and let it set, then took the blocks and prop out. I will fillet it on both sides later. I have got the bulkhead at stn 4 ready to glue in now. It's a more complicated bulkhead, but the general procedure will be much the same.
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  29. #274
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    Default Re: Kotik, Kotik, Kotik!

    Getting the bulkheads in is a huge waypoint in the project like this. Congratulations!

    Besides the little tank forward how much buoyancy is built into this design? I remember Iain's notes for the Eun Mara as being pretty non-committal as to whether or not what he had designed would do much more than just keep her afloat.
    Steve

    Boats, like whiskey, are all good.
    R.D Culler

  30. #275
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    Default Re: Kotik, Kotik, Kotik!

    Thanks, Steve. Yes, the bulkheads certainly do make it look as if progress is being made. It's taken a while to get onto them...
    As I recall, neither the Eun Mara nor the Wee Seal/Kotik plans make any promises about the boat staying afloat when full of water, but suggest that various spaces be closed in as much as possible, which I did on my EM and will do on Kotik. The "all one space" interior has the forward bulkhead at station 2, but the separate forward cabin requires it to be at station 1, which gives a much smaller buoyancy chamber. I will put a watertight hatch in the cabin bulkhead access to the space under the cockpit, and close in as much as possible around the cockpit.
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  31. #276
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    Default Re: Kotik, Kotik, Kotik!

    I think it gets really difficult to build in enough watertight volume to keep afloat and have places to keep your stores on a boat once you've added a big chunk of lead to the hull.

    Looking forward to your next installment. We've entered the cold wet season here, Marianita is battened down waiting for a nice day to go sailing again.
    Steve

    Boats, like whiskey, are all good.
    R.D Culler

  32. #277
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    Default Re: Kotik, Kotik, Kotik!

    I agree, and the lead on Kotik's keel (360kg) is twice the weight of Eun Mara's (180kg).

    We've just been away for another weekend sailing Sooty Tern Trondra with a couple of trailer-sailers on a hydro-lake we haven't had her on before. That's our last weekend away until January now, so my Kotik progress should pick up again.
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  33. #278
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    Default Re: Kotik, Kotik, Kotik!

    I have glued in the middle part of bulkhead 4 (and blocked the limber holes as I decided to keep the three main compartments separate),


    and glued bulkheads 4 and 6 up into manageable assemblies. I will glue them into the boat tomorrow.


    The hole is cut for the quarter-berth. There will be more battens to go on later, but this many will do for now.


    Cheers,
    Ian
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

  34. #279
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    Default Re: Kotik, Kotik, Kotik!

    Quote Originally Posted by IanMilne
    I have glued in the middle part of bulkhead 4 (and blocked the limber holes as I decided to keep the three main compartments separate),
    Ian, I am currently working on Oughtred's Ron Mhor (the bigger Grey Seal), and it seems very much like a larger version of Kotik, so I am following this thread closely. As much as I have come to really like the offset centerboard design, it does have the significant disadvantage of dividing the bilge up into 3 compartments as far has where water will settle. I am hoping to keep a limber whole through the middle bulkhead and reduce that to 2. Why did you decide otherwise?

  35. #280
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    Default Re: Kotik, Kotik, Kotik!

    Hi peb,
    I like the look of the Roan Mhor (Big Seal). (See http://www.oughtredboats.com/. Any chance of a thread on yours?
    I am blocking the limber holes at station 6 so that I can make the space under the cockpit into a watertight buoyancy compartment, and at station 4 so that water doesn't run the other way, into the forward cabin, if any gets into the main cabin (saloon). If any collects forward of the bulkhead, I can easily mop it out. That's my theory anyway. It's just another decision each builder has to make.
    I see the Roan Mhor has the offset centreboard. The only disadvantage that I can see with it is that it might cause a bit more drag when it's up than if it was inside the keel. Think about whether you want it on the port or the starboard side. The choice is yours.


    Yesterday I got the station 4 bulkhead glued in. The arch pieces at the top are held in temporarily to keep the posts straight. The posts are 24 1/2 " (620 mm apart, top and bottom.


    And today I got the main cabin bulkhead in, port side first, then starboard. I have raised the sill 3" (75 mm), and the cockpit sole at the forward end. I am also angling the seats downwards towards the centre to shed rain water when parked outside (level, of course). This detail was shown in the Eun na Mara plans.


    The two holes in the "off-centre" are for commercial plastic hatches to seal off the space under the cockpit, and for the "dry" half of the space inside the bridgedeck, for access from the cabin. The other half will have a lid in the top for access to the centreboard hoist, from the cockpit. I am thinking of a drum winch. The plans give no details of the hoisting system.


    Tomorrow I will fillet everything so far.

    Cheers,
    Ian
    Last edited by IanMilne; 11-22-2017 at 01:52 PM.
    “Old Joke: ‘A bench fitter works to the nearest thousandth of an inch. A loco fitter (steam) works to the nearest inch. A shipwright works to the nearest ship’.”
    Alan Byde, Canoe Design and Construction, Pelham Books, 1978

    “...old maxim, 'A fair line supersedes any given measurement'.”
    Allan H. Vaitses, Lofting, International Marine, 1980

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