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Thread: Building A Scow Moth.

  1. #1
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    Default Building A Scow Moth.

    This one should be fun. I’m really drawn to these ultra light building techniques. I got to spend some serious time with my jigsaw

    E9A668BB-E5A9-4456-AF05-A2ACEE9518A3.jpg
    Last edited by CK 17; 03-22-2021 at 08:40 PM.
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  2. #2
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    Default Re: Building A Scow Moth.

    Not too far from glider building techniques and a well sailed scow Moth can be a real flyer in a breeze.

  3. #3
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    Default Re: Building A Scow Moth.

    Interesting comment John. I learned most of my boat building skills helping my dad rebuild a glider. And CK 17, is this your design?

  4. #4
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    Default Re: Building A Scow Moth.

    Wow, do you have pictures of that glider rebuild?

    I got the plans from here:

    http://earwigoagin.blogspot.com/2011...ix_11.html?m=1
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  5. #5
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    Default Re: Building A Scow Moth.

    This is one of those moments when I wish iPhones were invented back in the 1960s. Film was too expensive and cameras too big to play the same documentation role that our phones play today. Here is the only photograph I have of the glider we rebuilt.

    Baby Bolus - Copy.jpg

    It is a Baby Albatross that was owned by Pete Bowers in Seattle. My dad had landed the glider a little too hard and the fuselage broke away from the rest of the glider, just below where the wings and tail boom are attached. This would have been around 1963. The glider was an antique at that time but my dad had worked in the Bowles factory, where the glider was built. This was after mustering out of the Air Force (Army Air Corp in those days) in 1945. Therefore, Dad knew how these gliders were built.

    That rough landing was on a grass field so the wings and tail surfaces were not damaged. The fuselage was the only part that had to be rebuilt. Dad spent several weeks disassembling the broken fuselage and copying the frames that defined the shape, much like Leo has done with his rebuild of the Tally Ho. I then learned how to laminate the frames from beautiful clear grain Sitka Spruce and resorcinol glue. The skin was 3mm mahogany plywood, which was shingled over the structure, once the frames were in place. I spent countless hours holding a bucking iron while Dad hammered the temporary nailing strips, that held the plywood in place while the glue dried. The resulting fuselage was finished bright with several coats of varnish.

    The photo was take after Dad test flew the glider. Not long after that flight the glider was donated to the Seattle Museum of Flight, where it was displayed for several years.
    Last edited by Mike.Higgins.94301; 03-22-2021 at 05:37 PM.

  6. #6
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    Default Re: Building A Scow Moth.

    Beautiful! Thank you.
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  7. #7
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    Default Re: Building A Scow Moth.

    Oooh I love scows. Some my favorite boat time was crewing on a neighbor’s C Scow when I was a kid. This will be a fun thread.

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    Default Re: Building A Scow Moth.

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  9. #9
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    Default Re: Building A Scow Moth.

    What woods are you using?

  10. #10
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    Default Re: Building A Scow Moth.

    3mm okume plywood and western red cedar for the struts. It will be planked in 1.5mm—if I can get it. Right now it’s mail order only and really pricey.
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  11. #11
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    Default Re: Building A Scow Moth.

    Quote Originally Posted by CK 17 View Post
    3mm okume plywood and western red cedar for the struts. It will be planked in 1.5mm—if I can get it. Right now it’s mail order only and really pricey.
    I don’t think 1.5mm ply counts as planking. That’s, like, sheeting, or skin, or covering. Plank? I don’t know. 1.5?! Man, that’s going to be see through!

    This is a neat boat I’d never heard of. Looks like a fiddly fun build, too.

  12. #12
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    Default Re: Building A Scow Moth.

    The strongback shape from 3mm. I’ll re-enforce with 25 by 10mm WRC cleats then glue more 3mm ply making up the other side for a total width of 31mm..

    78E2A93D-EDA3-4C93-A161-734B01CCCF7E.jpg
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  13. #13
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    Default Re: Building A Scow Moth.

    I believe I can see roughly where the daggerboard will go.

  14. #14
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    Default Re: Building A Scow Moth.

    Here are the approximate locations of the mast and daggerboard...

    B3400C3F-4C9B-41E4-B71A-BF23534CEC28.jpg
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  15. #15
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    Default Re: Building A Scow Moth.

    I’m getting well aquatinted with my dovetail saw...
    A5386BC7-7F75-421C-BECA-123159B65991.jpg
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  16. #16
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    Default Re: Building A Scow Moth.

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  17. #17
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    Default Re: Building A Scow Moth.

    The port side of the strongback will have a mirror image of 3mm ply applied after gluing in of the bracing and coating of all the surfaces.
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  18. #18
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    Default Re: Building A Scow Moth.

    Are you building a boat, or an airplane?!

    That looks super cool. I love when objects like that start and end. The wee, floppy bits become some amazing, rigid monolith, and it always makes me boggle. The strength to weight makes me giggle, too. We are clever apes.

    Thanks for documenting this cool build.

  19. #19
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    Default Re: Building A Scow Moth.

    Très cool. It's miles from what I imagine I'd ever build. I love everything about it.

    Also, just because this can't pass without comment, that picture of your dad and story are just wonderful, Mike. How many people walk away from a glider crash only to rebuild the thing with their kid? Heartwarming.

    James

  20. #20
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    Default Re: Building A Scow Moth.

    Quote Originally Posted by amish rob View Post
    Are you building a boat, or an airplane?!

    That looks super cool. I love when objects like that start and end. The wee, floppy bits become some amazing, rigid monolith, and it always makes me boggle. The strength to weight makes me giggle, too. We are clever apes.

    Thanks for documenting this cool build.

    You would have enjoyed seeing what the more creative Moth builders were doing in the mid-late 1970's.Much like this but with obsessive weight saving applied absolutely everywhere.I can't find the faded old photograph of me holding my hull above my head with one hand.A complete hull with wings might weigh less than 50lbs.Which helped those who could keep them upright to achieve tremendous speeds.A level of competence I never really got too close to.

  21. #21
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    Default Re: Building A Scow Moth.

    Our regatta, emphasis on the Moth. The first one was built by a member and it still exists.

    https://www.sail-world.com/news/215173/And-now-for-something-completely-different

    https://sgycinverloch.com.au/?page_id=1896

  22. #22
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    Default Re: Building A Scow Moth.

    CK, I have a question about the design of this elegant craft. Is the wood between the longitudinal stringers removed on the bottom of the frames, as shown in red?

    Station 1515.jpg

    If so, why? Is it for weight reduction or to avoid the need for limber holes? Assuming that you would add fillets where the frames meet the bottom panels, that would seem to eliminate a lot of the support you would have for that fragile 1.5mm bottom panel. Trying to avoid the need for limber holes would seem like a lost cause. This hull we need to be sponged out after every sail because of the water trapped by those longitudinal stringers.

  23. #23
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    Default Re: Building A Scow Moth.

    Quote Originally Posted by skuthorp View Post
    Our regatta, emphasis on the Moth. The first one was built by a member and it still exists.

    https://www.sail-world.com/news/215173/And-now-for-something-completely-different

    https://sgycinverloch.com.au/?page_id=1896
    Sku,

    I think your link should be https://www.sail-world.com/news/2151...tely-different not including the sgyc bit.

    Nick

  24. #24
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    Default Re: Building A Scow Moth.

    Quote Originally Posted by Mike.Higgins.94301 View Post
    CK, I have a question about the design of this elegant craft. Is the wood between the longitudinal stringers removed on the bottom of the frames, as shown in red?

    Station 1515.jpg

    If so, why? Is it for weight reduction or to avoid the need for limber holes? Assuming that you would add fillets where the frames meet the bottom panels, that would seem to eliminate a lot of the support you would have for that fragile 1.5mm bottom panel. Trying to avoid the need for limber holes would seem like a lost cause. This hull we need to be sponged out after every sail because of the water trapped by those longitudinal stringers.
    Although that is my understanding, for drainage, I’m not sure if that’s the route I’m going to take. I may simply drill through the frames after the bottom panels are on—or some combination of both...
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  25. #25
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    Default Re: Building A Scow Moth.

    After looking at the plans a second time I realized that I had misunderstood the design. The hull will be completely enclosed, like a paddle board. Therefore, you probably will put a drain hole somewhere, probably in the transom, so that any water that leaks in can be drained by standing that 40 pound hull on its stern.

    It is an elegant design, something like you would expect from a luthier. It is almost like you will be putting a mast on a double bass and taking it for a sail.

  26. #26
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    Default Re: Building A Scow Moth.

    A mate of mine got loaned one for the club centenary display on the proviso that he didn't bring it back.
    It is a pretty cool beast.
    No one is keen to give it a go though!

  27. #27
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    Default Re: Building A Scow Moth.

    Quote Originally Posted by CK 17 View Post
    Although that is my understanding, for drainage, I’m not sure if that’s the route I’m going to take. I may simply drill through the frames after the bottom panels are on—or some combination of both...

    Much less risky to cut the holes first when the ply skin is so thin.

  28. #28
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    Default Re: Building A Scow Moth.

    Closing in the center board case. This is so lightly constructed I could quite bring myself to follow the plans. I modified things by glassing the inside of the case and adding graphite powder. There will be more bracing added as the build progresses.
    6326B3CB-FA78-44C4-B573-C67A999441AC.jpg

    Also station 705 to 805 which is under the mast step.

    D64DF59D-B5A2-4926-9949-BAD72CA0D159.jpg
    sorry for the slow progress. I’ve been running down to the marina everyday to try and get the Oday in the water by the end of may. Yesterday was bottom paint day. Today the sky was spitting little ice balls while I patched the CB from when I hit bottom last season.
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  29. #29
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    Default Re: Building A Scow Moth.

    Sorry for the lack of progress. It’s gardening season and the honey do’s are coming from every direction. The Oday needed some work, but that is finally in the water. I’ll be building a building strongback box beam for the moth project to sit on next. I want this to be the least crookedly boat I’ve built
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