2 Hull

CREATING SCARF JOINTS    

     All that can be said today is scarf joints are a pain in the ass and had better be worth the effort.  I’m now on day # 3 of 20 minute spirts of hand planing scarfs in the hull plywood.  One more day and the first round of scarfs should be complete; then on to round two.  Pics to accompany when the scarfs are finished.

ONE SCARF COMPLETE

     5 days and 2.5 hours later, a pair of scarf joints are cut.  Now on to epoxying them together and then the fun begins again to add the final 3 ft. to the opposite edge.



SCARFING COMPLETE

     So I take back prior claims to scarf joints being too much work.  Turns out that the factory sharpened plane blade isn’t that sharp.  For the second round of scarf joints I purchased a cheap sharpening stone and put a nice blade on an otherwise ancient (but very nice) plane.  The new scarf took a total of 10 mins to set up, and 20 mins to plane;  I’ll take that over 2 1/2 hours of planing any day.  With scarfs complete, i’ve epoxied the first 20′ board with 2 scarfs. Here is a photo of the boards waiting for the epoxy to set.  This also marks the creation of the first piece that actually remains in the finished kayak.

                                                                                                                                                                                                                                                                                                   –

CUTTING THE HULL PANELS

     After a two week hiatus, there was time to continue again this halloween weekend.  Over the course of roughly 8 hours I was able to apply the printed hull plans to the scarfed sheets of okoume and cut the side and bottom panels.  I used packing tape to nearly laminate the printed plans to the plywood, starting in the middle working my way the front and back being careful to keep the paper plans flat and pulled tight to the wood with no rinkles or bubbles.  This took about 1.5 hours and about 2 rolls of packing tape.  I found the packing tape easier than spray mount glue because it didn’t require me to spray and control all 18′ of the paper at once; instead i could spread and tape the plans in several inch sections.

     Next, I used a jigsaw to begin cutting the panels starting with the bottom of the hull.  While it’s suggested to use a circular saw, I was just not confident enough that I could cut to the lines accurately.  To try and avoid an unfair edge, I spent about a half hour cutting each edge of the panels; cutting about 3 feet, and then going back to retape the paper and (2) plywood sheets together to avoid any shifting.  3′ clamps proved to be useful for supporting the outer edge while I made a second cut to seperate the bottom from the side panels since they were the perfect height.

     Once both the hull and side panels were fully cut and strapped together a few holes were drilled at the indicated marks on the plans for the copper wires to later be stitched through.  Finally to cap off the most productive weekend yet, the shop was rearranged for stitching the hull by setting up a shorter 16′ worktable thats perfectly level (i think).  The current hope is to finish stitching the hull by Thanksgiving.

 

–

SETTING UP EXTERNAL FORMS

     Over the past week there wasn’t much time so I was only able to seperate the paper plans from the hull panels and clean up the tape spots and and fraying edges in preperation for this weekend.  Today I was able to bevel the edges of the hull bottom and sides so they can fit together tight.  It only took about 1 1/2 hours; and, most of that time was spent figuring out the best plan of attack on the first panel. 

     Once the beveling was finished it was time to set up the external forms for stitching the hull together.  To do this I snapped a chalk line on the already leveled MDF table, marked off the location of each form in 1′ increments and scored a line perpendicular to the chalk.  Since I had well marked the external forms built awhile back, it was pretty easy to establish a few more centerlines to align with the marks on the table.  Once everything was marked, a few nails through the bases of the forms and I’m ready for the next step.  Just to be sure, before calling it a day, I stretched a string from the first form (form 1) to the last (form 16) to check by eye that everything was aligned.

–

–

–

STITCHING THE HULL

It’s been awhile since the my last post, and there’s been quite a bit of progress.  After the exterior forms were set up, leveled and aligned, I stitched the hull panels together with 3″ sections of copper wire.  The wires hold the panels together every 6 inches down the entire length of the hull on both the side and along the keel.  First I twisted a wire every 3′ to get everything set in its general location in the forms and to each other.  Then I went back and inserted the remaining wires and twisted them to tighten the fit between each of the panels adjusting as I went down the line.  95% of the them stitching without a hitch, but some just wouldn’t pull the panels tight so I added a few extra stitches, mostly around the keel.  The whole process took about 2 hours.

–

–

STEM FIX

Not all went smoothly with the hull stitching.  Stitching the tip of the bow and stern left an uneven joint between the side and bottom panels because I had overplaned the side panels.  To fix the problem I added an inner stem of cherry approximately 3/16″ to make up the difference in the two panels.  Once the inside of the hull is glass i’ll turn everything over and plane/sand down this stem even with the hull.  Also, since i think it will add some nice detail to the hull, I plan to laminate a small strip of cherry about 2-3′ long down the keel.

–

GLASSING HULL INTERIOR

With the hull stitched and stems fixed, it was time for the first layer of glass and epoxy.  Luckily some family with epoxy experience was in town this past weekend to help with my first time dealing with both epoxy and fiberglass.  All went rather well with no major issues.  First we sanded the interior of the hull to eliminate any burrs or sharp edges that might catch on the fiberglass cloth and stretch the weave.  Next we rolled out a layer of 6 oz. 30″ wide glass over the whole boat and moved it into place against the hull with our hands and a clean paintbrush.  I taped sections of newspaper on the outside of the hull to avoid excess epoxy from running over the edge and causing a mess on the outside.  Third was the big, and very unreversable, first coat of epoxy to wet out the glass.  While the goal of the first coat is to simply fill the weave with little extra epoxy on the surface; this isn’t as easy as it sounded.  Starting from the middle and working towards the ends we dumped small batches of clear epoxy and began working it around with a paintbrush and plastic squeegee trying to scrape away any excess.  In the end, it was extremely difficult to keep the layer of epoxy from pooling.  However, I can say with confidence that the glass didn’t float off the wood and there are no bubbles or empty spots.  Lastly, I sanded the areas of the hull that will be visible from the cockpit to even out the first coat of epoxy before i move on to a second coat this upcoming weekend.

–

EXTERNAL STEM DETAIL

Now that the inside of the hull has been glassed and epoxied with 2ish layers of epoxy, I was able to release the hull from the external forms and flip it over to begin work on the exterior.  I began by sanding the entire hull to remove drips and clean up/round over the joints between panels.  Then it was time to move onto the stem details which arose from an earlier issue that resulted in my adding an internal stem.  The new stem includes a layer of 3/16″ cherry sandwiched between the plywood side panels.  Then i laminated 3 layers of 1/8″ cherry onto the outside of the bow and stern with epoxy.  I held the laminations in place with some flat bungee cords purchased from lowe’s which work very well, holding the cherry firmly against the end of the kayak.  Once the epoxy cured it was time to shape and sand the otherwise ugly pieces to a beautiful new stem.  In total it took about 1.5 hours per stem and i’m extremely happy with the results.

GLASSING HULL EXTERIOR

It looks fantastic!  Today I spent about 3 hours laying down the glass and epoxying the exterior of the hull.  The exterior was incredibly easier than the interior since there’s really no worries regarding pooling of the epoxy and its just plain easier to work on the outside of the curve rather than the inside.(makes me want to redo the interior now that I have the hang of it).  I’m pleased to say that the outside came out absolutely perfect with a nice even texture from the fiberglass showing through and next to no glossy spots.  If time permits i’ll get to put down a second coat of epoxy this week and the hull will be finished!

HULL COMPLETE!

Its been awhile since my last update, but only for good reasons.  I have been able to get quite a bit done despite a rather hectic couple of weeks at work.  Since glassing the hull I trimmed the excess glass, did a light sanding and applied a second fill coat of epoxy.  Following the second fill coat I was a bit surprised to see the weave of the glass showing through and the texture still very apparent when running your hand along the hull.  I was on the verge of a third coat to help lose the texture but decided to post a question on guillemotkayaks.com regarding the issue.  Responses were helpful as always and I proceeded with a thorough sanding to knock down the high spots of the weave rather than adding unneccessary wait to fill in the low spots.  It took a good 3 hours of sanding with an orbital, palm, and hand sanding from grits 80 to start, down to 220 at the end.  This removed every last bit of the weave texture and now even babies wish they had bottoms this smooth.  Once again i wish i could go back to the inside of the hull and redo the glassing with what i know, but oh well.  Now that the hull is complete its on to the deck; but first, a quick pair of cradles.  I simply took two of the external forms and put some water pipe insulation on the edges which will come in contact with the hull, quick and easy, and costs 97 cents.