Page 15 of 16 FirstFirst ... 5141516 LastLast
Results 491 to 525 of 545

Thread: The believed abstraction of a 12 foot clinker dinghy.

  1. #491
    Join Date
    Nov 2010
    Location
    Wellington, NZ
    Posts
    945

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    I just painted with Dulux oil based enamel.
    How is it standing up to the knock's Ian? This is my concern, although my PT lives in a shed and only gets out for racing.

  2. #492
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Max F View Post
    Same with my morning coffee here.

    "I knew the stipple effect of the roller would show through the top coat but as most of this will be under the sole or ceiling battens I wasn't to concerned.
    I just preferred a good coat of paint over everything. The stipple effect is also good for hiding small blemishes on the hull surface and stray dust particles."

    I´m absolutely with you. Did the same on the interior and like it very much after I got used of the stipple look.
    For me it was also an exercise in relaxing my urge for perfection.


    Cheers
    Max




    It's a good idea to relax those perfection urges Max, this is a good way of proving to yourself that OCD is not an inherent part of your makeup.
    Cheers,
    Mike.

    Quote Originally Posted by IanMilne View Post
    All of the above, Mike. I use the Altex paints too, except for the blue on Kotik, which is Dulux, all single pot enamel, alkyd based.
    Cheers,
    Ian
    Hi Ian,

    I find the Altex Carboline paint range generally easy to use and get a finish that I'm happy with. Received a can of Enamel quick dry additive today from Altex which I will use on the hull exterior, hardens up the paint a bit.
    If I decide to add another coat to the sternsheet top I will use it for that as well.
    Hope all is well with you.
    Cheers,
    Mike.

    The enamel additive may be something to try on your PT hulls Slacko.

    Gave the stringers a coat of 207 epoxy mix and once dry fit them permanently into the boat complete with wooden plugs.
    The plugs were trimmed, a dab of epoxy to seal and I will give the inboard and top surfaces of the stringer one more coat of 207 later.

    IMG-5713.jpgIMG-5714.jpg

    The bulkhead hatches have had a second coat of undercoat.

    IMG-5710.jpg

    Now I am onto the dagger board case fitting.

    IMG-5719.jpgIMG-5738.jpg

    I levelled the dinghy athwartships and at the slot longitudinally, which is my datum point.
    A centre line was established using a straight edge and the case lined up with this and the slot.
    There is a small high spot on the keel which has to be removed so the case can sit hard against it, overall it was only out about .1 of a degree vertically on initial fitting.
    The idea is to have a removable case, to make repairs or adjustments.
    The plan is to 404 epoxy six short lengths of threaded rod into the keel that will line up with holes in the case logs.
    Acorn/dome nuts with penny washers will then be used to pull everything together.
    Focus on the effort not the outcome.

  3. #493
    Join Date
    Aug 2018
    Location
    Westminster, Maryland
    Posts
    83

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Hello Mike,

    I continue to be interested in the sequence/process you follow, and the materials you're using. Listing the names of the products you're using and why you are using them is informative to a new boat builder! So thank you again for your posts and photos.

    Beautiful results.
    When I read your first posts and saw the first photos I had NO idea that THIS is where this project was headed and that there would be these kinds of RESULTS!!!!

    Regards,
    Alan

  4. #494
    Join Date
    Nov 2008
    Location
    Schleswig Holstein Germany
    Posts
    943

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    This gets better and better.
    I too wouldn´t have expected such a transformation.
    Good to see her coming together.
    Great stuff Mike!
    Cheers
    Max

  5. #495
    Join Date
    Mar 2015
    Location
    Dunedin, New Zealand
    Posts
    870

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Like the others said, Mike. A removeable c/case is a great idea too, if you can seal it properly, and if the rest of the construction allows it. I'm sure you'll have no trouble!

    Hi Slacko, I just used the Dulux blue enamel on Kotik's sheerstrake because Altex didn't have that colour. It's got a bit of a mark on it where I bumped a pontoon. I'll touch it up some time, but it hasn't been a priority. It is generally well protected by upper and lower rubbing strips.

    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. #496
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Alan71 View Post
    Hello Mike,

    I continue to be interested in the sequence/process you follow, and the materials you're using. Listing the names of the products you're using and why you are using them is informative to a new boat builder! So thank you again for your posts and photos.

    Beautiful results.
    When I read your first posts and saw the first photos I had NO idea that THIS is where this project was headed and that there would be these kinds of RESULTS!!!!

    Regards,
    Alan
    Thanks Alan, glad to be of help.
    Now to be honest, in the beginning I had no idea where this project was going either. Initially it was a few repairs, a coat or two of paint, go sailing...yeah right.
    I have an evolving image in my mind of how I want it to look and the challenges that present themselves to create that look are fun to overcome.
    The building has the same level of enjoyment as the intended sailing, so no rush, it'll get there.

    Cheers,
    Mike.

    Quote Originally Posted by Max F View Post
    This gets better and better.
    I too wouldn´t have expected such a transformation.
    Good to see her coming together.
    Great stuff Mike!
    Cheers
    Max
    Expect the unexpected Max
    Cheers.

    Quote Originally Posted by IanMilne View Post
    Like the others said, Mike. A removeable c/case is a great idea too, if you can seal it properly, and if the rest of the construction allows it. I'm sure you'll have no trouble!

    Hi Slacko, I just used the Dulux blue enamel on Kotik's sheerstrake because Altex didn't have that colour. It's got a bit of a mark on it where I bumped a pontoon. I'll touch it up some time, but it hasn't been a priority. It is generally well protected by upper and lower rubbing strips.

    Cheers,
    Ian
    I have a few ideas about sealing the case Ian that involves splines or O rings maybe or just two opposing grooves that will fill with sealant.
    No final decision yet.
    Cheers,
    Mike.

    So, next was deciding on the setout of the bedlog fastenings.
    IMG-5748.jpgIMG-5749.jpg

    Went with the left photo setout, mainly because I liked the look but of course it will be a little stronger.
    I will use slightly smaller washers than shown, as these ones overhang the radius on the bedlogs a tad.
    The acorn nuts and washers will eventually be painted the same colour as the case logs.

    Now because I had not pre drilled the logs before assembling the case, this made for an interesting exercise.
    The distance between the log and the upper case ring frame did not allow a drill to be used in the vertical position.
    All the holes have to be as square and vertical as possible to allow the case to be removed without binding on the fasteners.

    IMG-5758.jpg

    Out with the ol' right angle attachment.
    By lining up the centre of the attachment housing with the grooves in the case and holding the housing against the case, thus keeping the drill parallel, meant the drilled hole would be plumb in both planes.
    A pilot hole was drilled using a 4mm Brad point point bit, this was then followed by a 6.5 mm twist drill bit. The threaded rod is 6mm. The hole will be soaked in epoxy then drilled again with the 6.5.

    IMG-5752.jpgIMG-5751.jpg

    Tested the drilled hole accuracy by checking the alignment of the rod with the grooves and case frame.
    Next post will be the installment rigmarole.
    Focus on the effort not the outcome.

  7. #497
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    The first task to installing the DB case was to make sure that the base of the case was flat and square to the vertical plane.

    IMG-5775.jpg
    IMG-5786.jpgIMG-5778.jpg

    The base was already fairly close to flat but there was a small hollow along one side that I felt needed to be addressed.
    I achieved this by placing the belt sander onto the horizontal plane, clamped the belt to keep it static then moved the case to and fro by hand.
    This allowed for a controlled removal of material.
    The case was then checked for square in two planes.

    IMG-5797.jpgIMG-5793.jpg

    The base was given two coats of epoxy.
    I had also prepared the keel by sanding with a long block to even out the bumps and hollows.
    A ring of masking tape was applied to create a raised border.
    The keel section was then given three coats of epoxy to build a base, which I would again sand with the long block to create a flatter plane.
    Focus on the effort not the outcome.

  8. #498
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Once the epoxy base had been sanded flat, I then covered the area with chalk, placed the case onto the chalk, gave it a few wiggles, this then highlighted the high spots on the case logs.

    IMG-5810.jpgIMG-5812.jpg

    A cabinet scraper was used to remove small amounts of epoxy. I would periodically check with the feeler gauge.
    The largest gap ended up at .003" or .076mm.

    A template was made as a router guide which to form a groove in the bottom plane of the case as well as the keel.

    IMG-5815.jpgIMG-5823.jpgIMG-5821.jpg

    These grooves line up with each other , the sealant will fill these to form an O ring when the case is permanently installed.
    Two small brass rods were placed into the template screw holes, these guide the base onto the correct position to align the grooves.
    Tomorrow I will begin to fit the threaded rod.
    Focus on the effort not the outcome.

  9. #499
    Join Date
    Mar 2019
    Location
    Rushworth, Australia
    Posts
    811

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Geez I wish I had some of your patience and skills Mike. You Continue to amaze me with your quality workmanship. Hopefully your lockdown doesn’t bother you too much (coming from the Capital of lockdowns - Victoria Australia. I think we’re on no.6 )

  10. #500
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Andrew Donald View Post
    Geez I wish I had some of your patience and skills Mike. You Continue to amaze me with your quality workmanship. Hopefully your lockdown doesn’t bother you too much (coming from the Capital of lockdowns - Victoria Australia. I think we’re on no.6 )
    Thanks Andrew, It is a no rush build and I enjoy the process.
    I like the lockdowns actually because it allows time in the workshop without the interruptions from the real job.
    We are currently L2 so near normal transmission has resumed with a few rules to abide by.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  11. #501
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Before drilling the anchor holes for the threaded rod the DB case was held firmly in place using threaded rod and a wooden block at each end.

    IMG-5824.jpgIMG-5825.jpg

    The right angle drill attachment with a drill bit fractionally smaller in diameter than the threaded rod was used to drill pilot holes into the keel, using the pre drilled holes in the case as a guide.
    The reason a smaller diameter drill was used is because the rod needs to thread itself into the timber, this is so it can support itself and also offer strength to the fixing.
    The first hole was drilled to a depth of 40 mm. Subsequent holes were drilled to a depth of 30 mm and increased in 2mm increments to a final diameter of 12mm.

    IMG-5836.jpgIMG-5828.jpg

    The rods have been temporarily screwed into place. I have slotted the top end so a flat blade screwdriver can be used to tighten them up.
    The rod length is quite critical because acorn nuts are being used. I hope to have them spot on for the final fix, to avoid using a grinder in the boat.
    The holes will be filled with a 404 epoxy mix.

    The video below is the initial dry fit. A good day.

    Last edited by Mike1902; 09-12-2021 at 04:08 AM.
    Focus on the effort not the outcome.

  12. #502
    Join Date
    Jun 2021
    Location
    Suffolk, UK
    Posts
    144

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Is it worth having a second "gasket" outside the line of the fixings? The inner one is keeping water from the outside from getting in under the case foot, but water in the bilge doesn't face such an obstacle getting into the joint.
    Last edited by Mike-in-Suffolk; 09-12-2021 at 11:36 AM.

  13. #503
    Join Date
    Nov 2008
    Location
    Schleswig Holstein Germany
    Posts
    943

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    I´m a little late this morning to write more.
    So It is just
    WOW!
    Cheers
    Max

  14. #504
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Mike-in-Suffolk View Post
    Is it worth having a second "gasket" outside the line of the fixings? The inner one is keeping water from the outside from getting in under the case foot, but water in the bilge doesn't face such an obstacle getting into the joint.
    Hi Mike, Thank you for the suggestion.
    I plan to lather sealant over the complete mating surfaces, most of which will squeeze out as the nuts are tightened but also form the O ring.
    Whatever other small gaps there are will be filled and should prevent any water ingress.
    The sealant will be flexible, white and paintable, so I will form a very small cove around the base and blend that into the hull finish.
    Sika 291 or 221 which is the automotive equivalent (and cheaper) are the front runners for this job. Removing the case could be a task but wedges and a sharp blade haven't failed me yet.
    Both surfaces and the holes have been sealed with epoxy to prevent water absorption as well.

    Cheers,
    Mike.

    Quote Originally Posted by Max F View Post
    I´m a little late this morning to write more.
    So It is just
    WOW!
    Cheers
    Max
    Hi Max,
    Late out of bed mate.
    Hasn't anything to do with all that heavy lifting has it?
    Well done on that BTW.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  15. #505
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Epoxied the studs in early this morning with the 404 blend.
    After pre priming the holes with straight epoxy the studs were screwed into place . Then using a syringe, the 404 was squirted into the void and poked with a thin stick to help remove air bubbles.

    IMG-5840.jpgIMG-5843.jpg

    Small plastic washers were placed over the holes to prevent adhesion to the case logs,
    The case was then lowered into position to hold the studs while the epoxy cured.

    IMG-5846.jpgIMG-5844.jpg

    Eight hours later, while the resin was in a hard rubbery state, the case was removed to avoid any potentially permanently stuck problems.
    It did take two pulls, as there was a bit of resin on the lower exposed threads.
    A few small voids in the top of the resin after settling but very shallow.
    After a clean up, I lowered the case back on and paced the nuts and washers on finger tight just to have a look see.

    Now onto the thwarts.
    Focus on the effort not the outcome.

  16. #506
    Join Date
    Nov 2008
    Location
    Schleswig Holstein Germany
    Posts
    943

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Hey Mike
    What a perfect job done.
    It is really a pleasure to follow your well explained steps.
    Keep it coming.
    It is interesting to see that advanced builders all over come to develop the same tricks/hacks and techniques.
    What you are doing is worth a million for all people who love to learn more about boatbuilding.
    Often I get so focused and absorbed into the work, that I forget to take the pictures that would explain techniques and steps.
    When reading your thread it allways remindes me that I wanted to do so. hahahaha
    Moving the c-board actually wasn´t that much hard work. Levers and my jack did all of it.
    I usually get short in time when I get up early and start to do some stuff just because I have so much time that day.
    And suddenly I realise I lost track of time and need to rush.

    Cheers
    Max

  17. #507
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Thank you for the positive comments there Max.
    If this thread helps to inspire anyone to build and create then that will be taken as a positive as well.
    Cheers,
    Mike.
    Last edited by Mike1902; 09-19-2021 at 12:42 AM.
    Focus on the effort not the outcome.

  18. #508
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    The following quickly drawn and not to scale sketch is to help explain the intended thwart layout.
    The thwarts will be removable to allow for sleeping arrangements.
    They will slot into the case ring frame and bolt through the stringer using wingnuts, this should lock and support everything in place across the boat.
    IMG-5897.jpgIMG-5853.jpg

    Once the dinghy was levelled, the measurements were established using the method in the upper right image.
    With the measurements found I calculated the underside curve using this deck camber formula.http://www.joliebrisemodels.co.uk/tenth/calculator.html

    IMG-5868.jpg

    By drawing the curve on the laminating table this allowed me to get the bevel for the top edge of each station bearer.
    Adding 20mm (3/4") to each station height, the bearers were cut to a length, this would allow both thwarts to be glued simultaneously.

    I will not go into the material prep at any length, as much of this is similar to past preparations in this thread.
    The timber used is Kauri, they are ex T & G sarking boards 20mm (3/4") thick, 20mm (8") wide and 3.4 metres (11' 2") long.
    First there was a fair amount of hessian tack removal, then cut slightly over length, followed by ripping to manageable widths (120mm and 80 mm), then placed on edge and ripped down the middle, edge glued back together making a 190mm wide board and thicknessed to 6 mm (1/4"). Six boards, three boards per thwart 850 L, 190 W and 19 thick.

    IMG-5870.jpgIMG-5873.jpg

    The laminates were bonded using the 403 filler epoxy mix.
    Focus on the effort not the outcome.

  19. #509
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    After curing overnight the thwarts where removed from the form and the edges cleaned up on the edge sander.
    The next step was to place a clashing strip along each edge. This would give the thwart a bit more width, 230 mm (9") , help protect the edge, cover the laminate joins and allow for a clear finish detail along each side.

    IMG-5885.jpgIMG-5887.jpg

    I had a nice clear Kauri board that had a bow in one end which pretty much matched the curve of the thwart.
    This was ripped into four strips and thicknessed to 20mm (3/4"), the thwarts were then placed edge on to each piece and marked accordingly.
    The strips were then bandsawn a couple of millimeters outside this line, they will be trimmed after they are permanently glued on.

    IMG-5889.jpgIMG-5890.jpg

    Three small holes were drilled along each strip, brass machine screws were inserted then the heads cut off to form a stud, these would locate into a corresponding hole in the thwart edge.
    The purpose of these are to hold the strip to it's lines and stop them wandering when gluing and clamping.

    IMG-5894.jpg

    The strips were bonded using 406 filler .The strips are relying solely on the glue bond with no mechanical fixings.
    They will be clear finished and I did not want plugs showing...and though you can make them near invisible.. they aren't.

    I used the 406 as it has a strong bond plus I used the left over mix to fill the nail holes in the timber.
    Most of the nail holes were cleaned out using a Dremmel tool. This was to remove any suspect wood around the hole damaged by the corroding steel tacks.
    This is the price that is paid using recycled timber... which is not that much really in my books.

    Once the thwarts have been cleaned up, the edge strips will be clear finished with 207 epoxy mix, the rest will have three coats of 205 epoxy then painted.
    Focus on the effort not the outcome.

  20. #510
    Join Date
    Oct 2006
    Location
    Irondequoit, NY
    Posts
    106

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Mike,

    Your thread makes great reading. So many good ideas for accurate and professional work. I'm making a list of them for use as I continue my project.

    Andrew

  21. #511
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Thanks Andrew.
    Glad to be of help.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  22. #512
    Join Date
    Nov 2008
    Location
    Schleswig Holstein Germany
    Posts
    943

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Man I love new posts of you with my morning coffe.
    One thing that came in my mind that the bolt is going to take some load.
    I would consider to carve out the thwart to embed it a bit into the stringer to reduce the shear load on the bolt.
    Or glue two slim blocks instead to the underside of the thwart.

    Cheers
    Max

  23. #513
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Max F View Post
    Man I love new posts of you with my morning coffe.
    One thing that came in my mind that the bolt is going to take some load.
    I would consider to carve out the thwart to embed it a bit into the stringer to reduce the shear load on the bolt.
    Or glue two slim blocks instead to the underside of the thwart.

    Cheers
    Max
    You have read my mind Max and thanks for your input, much appreciated.
    My quick and dirty sketch, though serving it's purpose, did however lack load bearing details.

    A tapered block has to be fastened to the top of the stringer. This is to create a surface that is parallel to the side slot in the DB case ring frame so the thwart can sit horizontally at the outboard end.
    The options are to rebate each end of the thwart to make a shoulder that will lie against both the DB ring frame and the tapered block. This could be reinforced with a strip of timber to thicken the shoulder.

    Now because I have altered the rig, the jib or stays'l will now fly off the forestay (see post #21) which will be attached to the stem head and not half a metre out on a bowsprit as originally designed.
    Because the dinghy is beamy, the lead for the sheets will be to far outboard. So the plan is to attach fairleads to the thwart and bring in the sheeting angle.

    The thwarts sit quite high in the boat, so the chance of the sheets damaging the coamings is lessened but something to consider as well.
    I am quite confident that the loads applied can be handled under the current configuration but.. I may add a stringer along the middle of the thwart on the under side, there are a couple of design options here to help spread the load.

    Just to add, I placed each end of the thwart on a block of wood, measured off the floor to a point on the arc, then stood on the middle of the thwart to measure the flex.
    I weigh 85 kilos (187 lbs) the thwart flexed 6 mm (1/4") , the thwarts are currently 850 mm (33 1/2 ") in length.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  24. #514
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    The edging strips on the thwarts were first trimmed close with a router, followed by sanding with a random orbital, then finished off with a fairing board with 80 grit.

    IMG-5902.jpgIMG-5909.jpg

    Using the router with an edge bead bit, this detail was applied to the lower edge along each side of the thwart, similar to that of the stringer.

    IMG-5910.jpgIMG-5911.jpg

    A 1/4 round matching the radius of the edge bead was routered along the top edge.
    These details help soften the edge and make the thwart look less chunky.
    Focus on the effort not the outcome.

  25. #515
    Join Date
    Aug 2018
    Location
    Westminster, Maryland
    Posts
    83

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Hello Mike,

    Your sense of where a little detail should be and what it should be certainly adds to the boat's appeal and also shows your abilities.

    I think you do lovely work!

    Regards,
    Alan

    I am a butcher!
    Not only am I a butcher....all I can make is hamburger.
    Last edited by Alan71; 09-21-2021 at 05:02 PM.

  26. #516
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Alan71 View Post
    Hello Mike,

    You sense of where a little detail should be and what it should be certainly adds to the boat's appeal and also shows your abilities.

    I think you do lovely work!

    Regards,
    Alan

    I am a butcher!
    Not only am I a butcher....all I can make is hamburger.
    Thank you again Alan for your compliments.

    Detailing, especially routered edge details can easily become a little overdone and the look starts to become busy.
    The idea of placing a bead on the thwart was mainly to soften the edge plus the groove highlights the arc of the timber.
    The bottom edge of the cockpit coaming will probably have this detail but that will be it.
    Sole boards and ceiling linings will be finished with a small radius only.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  27. #517
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    With the thwarts semi finished it was time to slot the upper ring frame of the DB case to make the housing for the thwarts to slide into.

    IMG-5921 (1).jpgIMG-5922.jpg

    The template was made from two layers of 3 mm MDF, these were glued together around the form of the DB case. Once dry, the slot was cut (allowing for the guide bush clearance) and then the template was placed and screwed into position.
    A router with a template guide bush attached was used to create the slot.

    IMG-5944.jpgIMG-5941.jpg

    The inboard end of each thwart was then shaped to match the slot, the outboard end was shaped parallel to the hull with a small gap allowing for thwart removal.
    Wedge shaped blocks made from a dense and close grained block of Matai were glued to the stringer as a bearing surface.

    IMG-5969.jpg

    The thwarts have now been shaped, epoxied, faired, epoxied twice more and sanded ready for 207 epoxy on the clashing strips and paint on the rest.
    The drilling of the holes for the fastenings connecting the thwart to the stringer is next.
    Last edited by Mike1902; 09-26-2021 at 09:22 PM.
    Focus on the effort not the outcome.

  28. #518
    Join Date
    Nov 2008
    Location
    Schleswig Holstein Germany
    Posts
    943

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    That arced thwart looks sexy!

    Cheers Max

  29. #519
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Max F View Post
    That arced thwart looks sexy!

    Cheers Max
    Thanks Max. Here's a slightly different perspective for your viewing pleasure.

    IMG-5968.jpg

    Just having a little think about fastening options at this time and maybe added support regarding load direction.
    Would prefer to keep it as clean looking as possible without compromising strength of course.
    I can always add support later I suppose if needs be.

    I'm also looking at shaping up the top of the case a bit more to get rid of the boxy appearance now that I know where the thwarts lay.

    Cheers,
    Mike.
    Last edited by Mike1902; 09-27-2021 at 04:13 AM.
    Focus on the effort not the outcome.

  30. #520
    Join Date
    Jun 2021
    Location
    Suffolk, UK
    Posts
    144

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Interesting. I love the arc on plan, but I am somewhat dubious about the arc on elevation. What does a curved bench top achieve? I'm not even sure it adds anything aesthetically. And there's this: it may just add a minor structural issue. Let me explain.

    If you have a flat beam, and you load it, it will deflect downwards. The effect on the location of the ends of the beam is that they are drawn inwards. Fine. Now, the same span, and this time the unloaded beam has an arc upwards to the middle. Apply the same load on this and the beam will deflect downwards........with the ends of the beam going outwards. If it deflects below the level of the supports it will then start to pull the ends back in again.*

    In the case of your seats, when loaded they will be applying pressure outwards into the hull, and inwards onto the dagger board case. If there is any flex at all in the dagger board case then the gap for the board will be squeezed slightly tighter. If there isn't, then the entirety of the forces will be outwards, pushing the hull out. Allowing for such movement isn't likely to be difficult, but it needs allowing for.

    *Builders habitually sight timber for joists and inevitably put any curve upwards. Their logic is that as the beams sag under their dead weight they will tend to get flat. However, the effect of that sagging is to push the walls apart. In masonry buildings (the norm here), that isn't great, because masonry resistes compresion well but tension really poorly, and so you can get cracking at the junction of lateral walls. I always instruct builders to place beams curve-down, which then has the effect of exerting an inward force on the walls, which is resisted well by walls at right angles..

  31. #521
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Mike-in-Suffolk View Post
    Interesting. I love the arc on plan, but I am somewhat dubious about the arc on elevation. What does a curved bench top achieve? I'm not even sure it adds anything aesthetically. And there's this: it may just add a minor structural issue. Let me explain.

    If you have a flat beam, and you load it, it will deflect downwards. The effect on the location of the ends of the beam is that they are drawn inwards. Fine. Now, the same span, and this time the unloaded beam has an arc upwards to the middle. Apply the same load on this and the beam will deflect downwards........with the ends of the beam going outwards. If it deflects below the level of the supports it will then start to pull the ends back in again.*

    In the case of your seats, when loaded they will be applying pressure outwards into the hull, and inwards onto the dagger board case. If there is any flex at all in the dagger board case then the gap for the board will be squeezed slightly tighter. If there isn't, then the entirety of the forces will be outwards, pushing the hull out. Allowing for such movement isn't likely to be difficult, but it needs allowing for.

    *Builders habitually sight timber for joists and inevitably put any curve upwards. Their logic is that as the beams sag under their dead weight they will tend to get flat. However, the effect of that sagging is to push the walls apart. In masonry buildings (the norm here), that isn't great, because masonry resistes compresion well but tension really poorly, and so you can get cracking at the junction of lateral walls. I always instruct builders to place beams curve-down, which then has the effect of exerting an inward force on the walls, which is resisted well by walls at right angles..
    Hi Mike,

    Thanks for a great reply and explanation. It's good to get opinions, keeps the mind active.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  32. #522
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Progress this week has been a little slow but it's still progress.
    I have made up the fastening bolts for the thwart fixing.

    IMG-5986.jpg

    These were made up of 8 mm SS threaded rod and SS tubing . The clearance between threaded rod and tubing wall is .3 mm.

    IMG-6006.jpg

    The thwarts were clamped in place and 10 mm holes ( slightly oversize to allow for the 404 epoxy mix) were carefully drilled through the thwarts ,wedge block and stringer, not a lot of room for error there.
    The tubing was held in place and in line with 8 mm fluted dowels and press fit plastic washers. The washers also lay between the thwart and the block to avoid gluing them together.

    IMG-6003.jpg

    Once the epoxy had cured the top dowel was cut flush and then the dowels were drilled out with an 8 mm bit down through the tubing.

    IMG-6002.jpgIMG-5999.jpg

    Wingnuts with spring washers and penny washers hold everything firmly in place.
    The bottom face of the stringer and the top face of the thwart are on different angles, so the stringer had to be chiseled out a touch so the washers would lay flat.
    All in all it is very firm with no athwartships play.
    The main load on the thwart will come from the jib sheets trying to lift them when sheet tension is present.
    I will keep the current configuration until sea trials and add any strengthening, of which there are a number of options, if needs be.
    Last edited by Mike1902; 10-03-2021 at 04:22 AM.
    Focus on the effort not the outcome.

  33. #523
    Join Date
    Aug 2018
    Location
    Westminster, Maryland
    Posts
    83

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Oh Mike!

    Each piece so thoughtfully planned and then beautifully made!!!

    I looked at the last photo before reading your text...I thought 'oh my' he even created a flat area for the penny washers so they'll sit level!!!!

    Your work really is inspiring.

    Regards,
    Alan

    As soon as I saw the thwarts in #519 I thought 'seagull'.

    What a pretty boat.

  34. #524
    Join Date
    Aug 2017
    Location
    Napier, Hawkes Bay NZ
    Posts
    460

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    Quote Originally Posted by Alan71 View Post
    Oh Mike!

    Each piece so thoughtfully planned and then beautifully made!!!

    I looked at the last photo before reading your text...I thought 'oh my' he even created a flat area for the penny washers so they'll sit level!!!!

    Your work really is inspiring.

    Regards,
    Alan

    As soon as I saw the thwarts in #519 I thought 'seagull'.

    What a pretty boat.
    Thanks Alan.
    Little things like getting the washers to sit flat and square certainly help prevent thread damage and cross threading problems later down the track.
    The acorn nuts were secured with Loctite thread lock.
    The tubing is mainly there to prevent wear from the threaded rod elongating the holes and rubbing through the epoxy sealer.
    The tubes also help spread the load across the stringer and prevent crush from overtightening the wingnuts.
    Even though everything is epoxy sealed, the thwarts will be removed when the boat is stored, so moisture is not sitting in between the mating surfaces.

    Ah yes, seagull, my thoughts were albatross. When the dagger board goes in, with the dolphin carving seated, they will look like giant pectoral fins.

    Good to know that you enjoy the posts Alan. Thanks again.

    Cheers,
    Mike.
    Focus on the effort not the outcome.

  35. #525
    Join Date
    Nov 2008
    Location
    Schleswig Holstein Germany
    Posts
    943

    Default Re: The believed abstraction of a 12 foot clinker dinghy.

    A+ for these tubings.
    Gluing them in with a dowel was a smart move too.
    Well I wouldn´t have expected less.
    Cheers
    Max

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •