Wednesday, March 28, 2018

Longboarding on a 26ft Sportfisherman

Kevin Agee has been longboarding the past two weeks. This is not the type of longboarding that I do, surfing the waves on the longest of my surfboards. The longboarding that Kevin is doing is with a flexible board about 1m long, with a pair of handles on one side and coarse sandpaper on the other. This involves application of much elbow grease, removing any surface epoxy glue oozings left after initial cleanup when fitting the strip cedar skin, as well as high spots in the timber surfaces.

As part of the process, low spots are filled with lightweight epoxy filler, thereby reducing the amount of material that must be sanded off surrounding areas to smooth out the surface.

Boat with the pox. The grey patches are areas where hollows have been filled and then sanded flush. 
After that comes more sanding and more filling and more sanding and so on, until you are happy with the surface. A side benefit is some weight gain in arm, shoulder and trunk muscles.

The chine is also faired as part of fairing the hull sides. This is done by first trimming off the overlapping side planking at the chine, then planing them flush with the planks of the chine flat. Any unfairness in the chine flat must be faired by sanding/filling, the same as for the side planking. The hull will be glass-sheathed, so the hard corner of the chine must be rounded off to a radius suitable for the glass fabric.

Also forming part of the fairing process is filling in the holes where temporary screw have been removed. This is normally done by injecting or squeezing filled epoxy into the holes, then sanding smooth. Kevin used an alternative method that is quicker and easier. He used wooden golf tees, epoxied into the holes. After the epoxy has cured the tees are cut off flush.

Another job that is going on is fitting the keel runner. The runner is laminated in place on the hull from two 20mm (3/4") thicknesses but it needs a flat surface on the hull centerline onto which it can be bonded. This flat is rough-formed with a power plane then finished with a hand plane. The flat is continued all the way to the tip of the stem. In the forefoot area the runner tapers off and fairs into the hull to become a laminated stem capping. The stem capping must follow the tight curves of the stem profile, so it has to be done in much thinner strips than can be used for the keel runner.
The keel runner being glued in place onto the flat that has been planed on hull centerline. The chine flat is also being faired.
The stem capping is being glued up one layer at a time from stock that is 1/3 of the thickness used for the keel runner. This slows the process because the epoxy glue must have initial cure before the temporary screws can be removed and the next layer glued on. Multiple layers will build up the capping until the timber can be shaped into the bow profile that we want. The shaping is most easily done in stages, after every two or three laminations.
First layer of the stem capping has been glued on
He has been trimming the sheer as well. All of these features coming together are now giving the hull more definition, so the final hull shape is starting to show.
Final shape starting to show due to crisper lines to catch the eye.
The drawings for this design are still in progress and the design is not yet on our website. To see our designs, go to our main website or our mobile website.

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