Hawila’s refit in Holbæk 2020-2021

    In September 2020, Hawila started a massive refit in Holbæk, Denmark, to be converted as a commercial sailing cargo vessel. The refit will last until November 2021 when she will set sail again.

    The entire forward part of the vessel was dismantled, keeping only the machine room, galley and navigation room. The keelson has been changed with a bigger and stronger piece, the entire steam assembly and stem frames were replaced with new oak, as well as about 1/3 of the ship’s bottom frames. An additional 16 floor timbers were added to the ship structure to increase the strength and insure connection with the future bulkheads. The new hull planks are increased in thickness from 50mm to 65mm and the rabbet connection with the keel has been entirely recarved and restored.

    Above water line, the entire deck and scandeck will be replaced together with 4 of the cross ship deck beams, mostly in the aft section of the ship. Mid ship hull planks above water line will also be changed together with a dozen of the top frames. One impact bulkhead will be added forward of the ship, together with 3 structural watertight bulkheads in the mid-ship to aft sections to comply with SOLAS regulations.

    To finish, the entire rigging will be inspected and the entire sail canvas will be replaced to new according to a slightly modified sail plan.


    Below are some technical informations about the refit:


    How to change a frame on Hawila?

    After two weeks of holidays break, we are all back at the shipyard! The carpenters of the framing team started their work right away on the many frames that need to be replaced.

    Our frames are made of several oak futtocks. On Hawila, some of the futtocks are still in good shape -even after 85 years of use- and some have been replaced more recently. Therefore, we replace the ones showing rot or structural damages due to many years of service.

    One by one, the fastenings are removed and the futtocks are taken out. The old surfaces are cleaned and planned to welcome a template that will be used to represent the new futtock. The plywood template is placed against the remaining frame and cut at the right dimensions. All the necessary measurements for the new frame are written on this plywood template (angles, length of the piece, frame number, location in the ship etc).The template is then used to find a suitable piece of oak from our timber supply, we also check to ensure that we have the desired grain in the wood ensuring strength. We then can mark the contour of the frame as well as the edge angles on the fresh timber piece before cutting.

    We use a chainsaw mounted on a jig allowing us to change slowly the cut angles along the frame cut line. The chainsaw jig was welded by Sam using scrap metal from the yard, inspired from the jigs utilized by the ships Ceiba and Tally Ho. The cutting process is done by a team of two: one pulling the jig and following the cut line, the other adjusting the angle along the way. After that, the final frame surface is planed more precisely in the workshop according to the same angles reported on the template. The piece is now ready to reach its place in the ship where final adjustments are made.


    How to fasten our frames on Hawila?

    After being cut to specification, each frame futtock is dry fitted in position: the final adjustments can be made before the futtock is fastened to the other frame.

    Before fastening, all future wood-to-wood contacts are painted with anti-fungal paint, and later coated with putty mix. This putty, also known as linseed oil putty mix- is a homemade blend of linoilkit, pine tar, linseed oil, and hemp fibers. The putty is used to smooth the irregularities remaining between new and old frame futtocks and also act as a strong anti-fungal agent.

    To fasten the frames together we use treenails: a long wooden nail made of dry oak and wedged on each side. The concept with treenails is to use the expanding properties of the wood to fasten pieces together. We use well-seasoned timber with a moisture content below 14% to make treenails of 25,4mm (1 inch) diameter. We then hammer them into a 25mm drilled hole, and finish by wedging each end. By using green timber for framing, our treenail will expand to stabilise at a higher moisture content, ensuring additional friction (measured timber moisture content in Hawila’s bilge is stable at about 18-20%). This technic has been used traditionally as a reliable fastening on all kind of ships and construction and from our experience, presents a longer lasting fastening solution than galvanised bolts in oak.

    To produce the treenails, rectangular lengths of 26x26mm are cut from well-seasoned oak planks, following the grain and avoiding knots and cracks. The wood pieces are then planed, thicknessed, and the edge of the square pieces are cut with our Felder table saw and a homemade jig. The treenails are rounded to 25,4mm using a drill with welded metal support and a Veritas 1″ tenon cutter cut at the end.

    Before inserting the nail, we coat the holes with pine tar to lubricate the insertion and act as anti-fungi.

    The new futtocks are now ready to be faired!


    Hawila’s new stem assembly

    In a wooden sailing ship, the apron nd astem deadwoods are often difficult to access. The stem is the part of the ship located at the very front, the “near vertical” continuation of the “horizontal” keel.

    The stem on Hawila is composed of two pieces : the outerstem -the above water part- and the forefoot -the curved junction between the outerstem and the keel-. Inside the ship, the stem is reinforced by deadwood pieces and the apron right behind the stem. The role of this structure is to add strength to the stem and make the connection between the stem, the keel, the keelson and the frames. Frames are bolted to those pieces and often deadwoods have assemblies above and below the keelson, making them hard to remove without removing planking, frames and keelson.

    Leif and Marvin, two german boat builders, came especially to help us with the rebuilding of the entire apron and modifying the stem assembly. The only piece we chose to keep, is the actual stem, which is in a very good state of preservation.

    First, Leif and Marvin had to remove the metal casing covering the forward keel/forefoot and take off the bolts that were holding the deadwoods to the stem, keel and keelson. After cleaning the surface, they used plywood templates to mirror the shape of the future deadwoods and apron. In a similar way as for framing, they chose the timber showing the best grain direction, ensuring strength to the piece.

    Pieces are cut, planed, and placed in position one by one, helped with tackles and blocks to ease the lift. Once fitted, we lift them again and use anti-fungal paint and pine tar at each wood to wood surface. To finish, the pieces are clamped firmly before being bolted with galvanised 20mm steel bars, threaded in each end by our local blacksmith. Later, when the keelson will be sandwiched with the last overlying knee, 24mm bars will be used to bolt the pieces to the keel. And finally we will carve a new rabbet all the way on the keel and the stem.

    Hawila was built as a motor sailor in 1935, and in the 80’s was heavily refitted with a larger rigging and a big bowsprit. Today this whole assembly seems too weak to withstand the forces of the foresails, and the crew had noticed a slight and slow move aft of the stem and bowsprit over the years while sailing. As a result we chose to increase the sizes of the deadwoods and apron and add a large overlapping knee to add more strength to the all assembly. Later in the process, this knee will be incorporated into the forward impact bulkhead to ensure even more stability over the years and the seas to come…

    Thank you Leif and Marvin for your amazing and efficient work !

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