Blackrock 24 (Build)

Discussion in 'Wooden Boat Building and Restoration' started by LP, Mar 12, 2013.

  1. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Getting Cheeky

    Or, "How to make a square mast fit in a round hole."

    Mast building continues. I've added the cheek pieces where to mast penetrated the deck. The cheeks serve a dual purpose. First is to "round out" the mast to fulfill it's roll as a rotating mast. Secondly, the strength boost given by the cheeks was considered and accounted for in the design and used to minimize the section size at the deck. The side cheeks were also run up the sides of the mast to increase section strength where it's needed. The lower portions of the mast (deck down) are solid and contribute a fair portion to the weight of the mast. This extra weight down low should should give some good counter balance while stepping the mast. Once above the deck, the mast is hollow except at the boom attach location and the top 16 of so inches. Both masts will have a 5.5" diameter at the deck. The mizzen though, will be hollow at the deck and the cheeking will really only serve to round out the mast. I could have made the mizzen smaller at the deck, but the added size will let it step in the bow if something happens to the main.

    Cheeky in the rough.

    IMG_0444.JPG

    Rounded and smoothed.

    IMG_0447.JPG IMG_0448.JPG

    My mast lathe. :D Four goes to eight. Eight goes to sixteen. Sixteen will get you 20. :eek: 32 actually with the power planner and then the 36 grit sanding belt came into play. It does a pretty decent job and gives a bit of a work out in the process. Hoorah!

    IMG_0449.JPG

    Looking bright with a fresh coat of epoxy.

    IMG_0451.JPG

    If you are using an Apple product or Chrome to view the images, I apologize. I've oriented them properly, but these product know the original orientation of the photos and revert them back. If any one knows how to fix it, please let me know how to do it. Windows Explorer displays them properly.
     
  2. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Pictorial update.
     

    Attached Files:

  3. latestarter
    Joined: Jul 2010
    Posts: 402
    Likes: 51, Points: 28, Legacy Rep: 233
    Location: N.W. England

    latestarter Senior Member

    Thank you for the update, I was wondering recently how you were getting on.
    Excellent finish, e.g. mirror image on the transom.
     
  4. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Thanks for stopping LS. I don't spend a lot of time here at the moment so updates are a bit slow in coming. The free time goes into building and posting gets put off.

    Im attaching a collage of photos from back in the spring. I had finished construction on my masts and did a bend test so I could send the results to the sail maker.

    Life's coming at me fast and crazy at the moment and I haven't been able to get my suit of sails ordered yet. That will be an exciting when they arrive.

    The boom in the photos is the main boom and the mast that has the wiring in it is the mizzenmast. Three wires: one for the all-around and one for a spreader light with a common ground.
     

    Attached Files:

  5. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    IMG_0982.JPG The "Rock" in its new Florida home. It's been a busy summer packing up and moving so little (as in "no") building has taken place. The big milestone was getting it on the trailer so I feel infinitely closer to getting her wet in the near future.

    I'll be concentrating on completing the exterior finish and completing the rudder. I could probably float her today and use the kicker motor for steerage and making way, but I want to have her all dressed up though for her water debut.

    I have some minor work at the pardners to do before I can step the masts. The holes are slightly under sized so they will get opened up to allow maximum freedom of movement for the masts.

    I'm hoping to have more updates in the near future.
     
  6. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Stepping it up.

    I stepped both masts for the first time a few days ago. No major snafus (sic) fortunately. Both were designed to be stepped single handedly and worked as planned.

    The main has a lot of for-n-aft slop, but that is intentional to give some accommodation for balance. Once balance is dialed in, I will make a tighter, permanent step. The mizzenmast dropped in as planned, but was tight due to a mismatch in rake of the mast and rake of the step. I redrilled the step at the right angle and all fit together nicely. I may add additional guides to assist in stepping the mizzen mast. At the very least, I will add a layer of biax where the mast heel rides down the transom while being stepped.

    Progress continues.
     

    Attached Files:

  7. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Do you have a close up of the steps and such? Good to see your post again.
     
  8. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Hey, Paul. Good of you to drop in. I'll see what I can do, but it's going to be a few day before I can post any pictures of the steps.

    I'll go ahead put a photo up of yesterday's progress. I've been focusing on getting the cockpit details constructed. Primarily, the cowling for the kicker motor and motor well. The cockpit is to the point where I was comfortable to start working the finish.

    I primered the entire cockpit yesterday and it looks sweet. I wish I was able to continue and get it painted too.
     

    Attached Files:

  9. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I remember the decision process of some of these choices and it's nice to see them in 3D, clean and sorted.
     
  10. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    The cockpit redesign was a major change that put a lot of hours on the project. Changes on the fly really take time and (for me at least) a lot of thought process. In the initial design process, you expect changes and it's all part of the process. One change may initiate another and then, maybe another, but it's all on paper. Once there is structure in place, it's a whole new ballgame with, sometimes, irreversible consequences. The first cuts into existing structure on a redesign is kind of like rappelling off a cliff. Once you start, it's going to be a lot of work to get back to where you were.

    I'm happy with the way the cockpit has turned out and I think it's going to be a lot more ergonomic that the traditional style bench seating the is so common to this size of sailboat.

    It's a very exciting time as sea trials are on the near horizon. It's mostly primer and finish. I'm still constructing my rudderhead and tiller. I'm also pondering a modification to my centerboard. It's is quite massive being built out of solid yellow pine. Since I've chosen a "slice o pie" style of board that forms a delta wing shape while extended, I was toying with putting a sharp edge on it to induce the twin vortex circulation structure that developes on delta wing plan forms. I'm probably thinking too much (and living on the planet of wishful thinking) and the sharp edge is going to be susceptible damage. The positives are that it lightens the centerboard and pulls buoyancy from its lower portions. This would allow it to naturally sink lower in the water without much additional ballast. Comment anyone?

    Off to work. Thanks to everyone that follows this thread. I'm hoping for floating very soon.
     
  11. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Hey there, Paul. Six million weeks later, I get some photos up of my mast steps. I leave the interpretation up to you. Feel free to ask questions.

    IMG_0695.JPG IMG_0696.JPG
     
  12. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    And.....a non-pictorial update. I'm concentrating on getting paint on all exterior surfaces. Everything has been primed and hit with a first coat of paint on the hull proper. The pop-top hatch is the same. The mizzenmast has two coats and paint accents to be added. First order of business though, is to get the final finish coat on everything on the hull. I'm waiting to post pics until I can unmask everything.

    I've made a replacement hatch for the one that goes on the pop-top. It went missing in the move to Florida. I've shaped the rudder finally. It's been sitting as a rough core for about five years as a testament to my original failure in trying to shape it. It has a tapered profile and I was planning to do a 6-digit naca foil. Ha! I said, "Forget that stuff!" I eye-balled its foil shape with a power planer, beltsander and mast rounding techniques. A radiused leading edge and a tapered trailing edge would have served me just fine, so anything more refined that that I'd an improvement.

    The to-do's before boat soaking will be completion of the rudder head and making (laminating) the tiller.

    The final bit of construction will be a bit of surgery on the main mast. It is too rigid (and heavy). I'm going to peel off the forward stave down to almost deck level, remove some unnecessary inner structure (boom attach mod), reshape the side staves and reduce fore and aft stave thicknesses once it's glued back together.
     
  13. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Just a couple of photos. Exterior finish sans trim and and non-skid paints. Paint drips included. All varnished areas will get a 320 sanding and one or two more coats to freshen up those areas.

    I've reached out to Florida Fish and Wildlife to get going on the requires inspection to get it titled and registered.

    Exciting stuff.

    IMG_1316.JPG IMG_1317.JPG
     
  14. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Committing a-surgery!

    My victim/patient is a my 29' main mast that has too much mid-section and is too stiff for my purposes.


    IMG_0719.JPG IMG_0720.JPG

    I built the main mast first when I should have built the smaller mizzenmast as my first attempt at a free standing mast. To err on the side of caution (strength), I was casual in designing the sections and trimming the stave thicknesses. Also, my original plan had the wishbones mounted higher up the mast and penetrating it. Blocking was built into the mast at the boom attach to help distribute those loads. Right or wrong, I decided to lower the boom attechment for for perceived improvements in line handling.

    The plan: Remove the forward stave down to the boom attach point so I could trim the side staves and remove the internal blocking that was no longer needed, reglue the forward stave and finally shave the for-n-aft stave thicknesses to 20% of the mast section.

    The instrument of deconstruction:

    IMG_0721.JPG

    Could be dangerous! Blade depth was set to side stave thickness and the saw guide was set to forward stave thickness. Cut depth was kept to a minimum to limit damage should I wander off course.

    And the results.

    IMG_0722.JPG

    The clean up artist:

    IMG_0723.JPG

    The shallow cuts proved to be useful guides for the hand saw in the solid areas.

    The split:

    IMG_0724.JPG

    As it turned out, digging out the internal block proved to be quite difficult with the stave in place and it would limit my ability to trim the for-n-aft dimension. It didn't take long to justify full removal of the entire stave.

    The separation:

    IMG_0725.JPG

    With a peek inside where the blocking used to be.

    IMG_0726.JPG


    Definitely a good move as bigger power tools could now be freely used. I trimmed the side staves with a power planer to reduce their depth (for-n-aft) and reglued the forward stave. Once the epoxy set, I trimmed the forward stave to 20% thickness. At that point, I decided to hold off on trimming the aft stave thickness. The mast is definitely more limber so I'll save trimming the aft in the event I feel it is necessary to further increase limberness in the mast.

    The pile excess material remove from the mast.

    IMG_0727.JPG

    I am so glad this task is done. The mizzenmast is already painted with track and hardware being fitted. It will be nice to get the mainmast caught up to the same place. Additionally, it's simply great to have this daunting task completed. The construction phase of the project is quickly winding down. Paint and finish is progressing nicely also. Hardware and rigging are in hot pursuit.

    Very exciting times indeed.
     
    Last edited: May 11, 2018

  15. LP
    Joined: Jul 2005
    Posts: 1,418
    Likes: 58, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Not a lot going on visually. In Florida, homebuilt boats need to have an inspection by the FWS (Fish and Wildlife Service). It's not so much of a safety inspection as it is to confirm that the hull is not a pre-existing and registered hull. I think there is a general overview of seaworthiness, but nothing in depth. Seems they were mostly interested in seeing receipts for material purchases. I'd never had to do that before, so in the moving process, I had tossed most all of them. I was able to contact my material vendors and came with with significant amount of purchased materiel receipts that seemed to satisfy the FWS. I also had a "few" pictures of the build, too. Anyway, I've had that inspection completed and the hull is now a registered hull with ID numbers. A big thumbs up there!

    I'm continuing to finish the standing rig. Pretty much, just a coat or two of paint. I've included a pic of the wishbone booms and masts. PAR was instrumental in me using this type of boom as he shared some drawing with a very simple attachement (gooseneck-you might say) design. Both are now painted except for accents. The main is an "H" section that places the most material along designed load paths. Simple metal straps across the top or bottom of the H will act as fair leads any "internal" control lines that run along the boom. The boom is a little bouncey in the vertical direction so we will see if that is a problem under way. The mizzen boom is a square section that is proving to be rigid in all directions. At some point, I may try to run internal lines on it also, but I haven't fully decided where and how all of the control lines will run.

    I've also included a shot of the masts. Surgery is complete on the main. Big news is that my sails have come in so I've very excited to stand the rig, hoist the sails and start finalizing the control lines.
     

    Attached Files:

Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.