The daggerboard case got framed up today. Inside of the case will be lined with outdoor carpet to make the board slide with slight friction. The hope is that the board will stay at any height you put it and that the carpet will protect the daggerboard finish. I mocked it all up on the bench first, with oversize spacers then took a bit off the spacers until the friction felt about right. Don't know how this will behave once wet and after the carpet ages a bit but I'm planning on gluing the carpet in only at the top and bottom so that it can be cut/chiseled/beaten out of the daggerboard case if tweaks are needed.
Test fit to get the inside clearance for the daggerboard just right.
Now that the bottom is on, we turned the boat over again and trimmed the bottom to the hull sides then rounded the chine to a nice radius. The hull is starting to get a bit to heavy for Kristi to turn over in the air so we carry it into the yard set it in the grass then roll. It's still pretty easy for the two of us to carry around. The bottom trimming and rounding took a good bit longer than planned, yeah I know what's new. First of all, I could not find my laminate trimming bit for the router so instead of stopping and going to the store for another one I decided to just man up and hand plane the bottom to size. In retrospect this was a mistake as it took way to long. And by the time I got the the last mm, where you have to be a bit careful to not gouge the hull sides, serious fatigue was setting in. Fortunately Sanding Queen (queue ABBA) had just gotten back from a Christmas party (no spouses yey) so she was able to come in and help finish the job :-)
You can dance, you can jive, having the time of your life
See that girl, watch that scene, dig in the sanding queen, oh yeah.....
Hull bottom trimmed, sanded and ready for epoxy coat.
Closeup of radiused chine. I find it tricky to hand sand a nice even radius in solid wood but it's a lot easier in ply as the layers act like gages. If the lines formed by the ply layers are parallel and not wavy then the radius is reasonably constant.
First coat of epoxy is on. Only one coat for now. I wanted to have the wood sealed so that it would be ding resistant. Plus I can work on the boat outside and not worry about a lttle water splashning on it. The last two coats will go on at the same time as the chines get fiberglass tape.
The bottom panel butt splice epoxy cured overnight. Today we cut and installed the bottom panel but first I had to cut limber holes in two bulkheads.
Clamped on a piece of scrap ply with a pilot hole in it to guide the hole saw.
Cutting limber hole.
All done, just a bit of sanding to clean it up.
Marking out the hull profile on the bottom panel.
Taking a break while the hull bottom outline is lofted.
Hull bottom cut out.
Hull and bottom ready for dry fit.
We propped the bottom up over the hull before applying the epoxy in an attempt to keep as much of the goo from getting all over the bottom, while positioning. We started screwing down at the bow and proceeded to the stern removing the supports as we went. This worked well.
Bottom is on.
Excess epoxy squozeout got cleaned up to minimize sanding later.
So you remember that little crack that formed in one of the chinelogs as we were assembling the hull? Well it got bigger. I think it happened as we were flipping the hull, since it gets stressed in different directions when you do that. This crack growing may actually be a good thing as it allowed me to fix a little unfairness that crept into the bow area. The side of the hull that had the intact chinelog had a bit of a kink where the stem ended and the chinelog began but the cracked side is beautifully fair. Since I like the fair side better I induced the same crack in the intact chinelog and now both sides look great. A big dollop of epoxy makes it all OK.
All of this is a result of me thinking I was being clever and not following the plans. Michael Storer, the designer, specifies that the chinelogs should end 50mm short of the bow-end of the hull sides. But I noticed that the stem is significantly less deep than that so you end up with a gap. Silly designer, says I, I'm going to extend the chinelogs all the way to the stem and make it all pretty. Well, if you do that what happens is that the two chinelog ends hit each other as you bend the hull sides around the first bulkhead, doh!
I took the pull saw and viciously hacked away chunks of the offending chine logs. THAT will teach them and nobody will see the butchery since all this is inside the floatation chamber. The hull went together beautifully. Except now with the chinelogs not touching each other the hull sides are not quite fair just aft of the bow and the gap between the chinelogs allowed the chinelog to split away from the hull side. How much do you want to bet that if I had cut the chinelogs 50mm from the hull end, as instructed, they would have come together and just touched thereby preventing that slightly unfair hollow and since they would be touching each other they could not separate from the ply. Silly builder.
BTW, the chinelog that pulled away from the hull side was a secondary joint since that hull side was epoxy coated all over, without masking the joint areas. The epoxy was well sanded with 60 grit, in the glue joint. It looks like it's mostly the wood and not the epoxy that failed but it's a little hard to tell. The side which did not fail had the joint areas masked before epoxy coating so that joint is wood to wood. Coincidence or is that side a stronger joint? You decide.
The chinelog on the left has separated from the hull side while the one on the right has only a bit of a crack. It is mostly hanging on but is causing an unfair hollow just aft of the stem.
So the solution is to separate the other chinelog from the hull side by the same amount. I used a small steel scraper, as a wedge, to shear the cedar away from the hull side.
I taped the underside with some packing tape to form a dam and filled all of the cracks with slightly thickend epoxy. It's ugly but stout.
The epoxy had set nicely overnight so it was time to flip the boat over and plane the chinelogs flat to accept the bottom panel. We turned the boat upside down and placed it on two sawhorses. Rather than trying to support the hull by the still somewhat flimsy hull sides we placed the saw horses under bulkheads. This put the boat at a perfect height for putting some ass behind the plane. The plane does not like hitting the epoxy joints between the bulkheads and hull sides. I first used a coarse rasp to knock down the epoxy goobers so that the plane would not get hung up on them.
Up on sawhorses
From the stern
The deckplate cutouts provided the perfect place to clamp the boat to the sawhorse for stability.
Having at the chinelog. Cedar is so easy to work with a sharp plane.
Used a long level to check that the bevel angle planed into the chinelogs was just right for the bottom panel to lay flush.
I decided to plane down to the outside edge of the ply rather than planing to the inside edge. I did this mainly out of laziness but also because the bulkheads were aligned with this edge so it saved a lot of planing of the bulkheads. The little void will be filled with thickened epoxy which may, as a side benefit, toughen up the chine some and help prevent denting from rocks etc...... maybe.
We trial fitted the boat to it's trailer. The trailer is our old kayak trailer so now we will have to load kayaks up onto the roof rack. That's no fun but we can't have any more trailers in the yard :-) I'm planning on replacing the tongue with a slightly longer one and extending some wooden bunks aft to support more of the stern. The boat will live on this trailer for the rest of the build which makes it easy to move around.
We left the hull dry assembled overnight and began the epoxying of all the bulkheads this morning. Rather than working hunched over on the floor we elevated the hull onto a sawhorse and a folding table. This worked well and gave us easy access all around the bulkheads. I noticed that a couple of the bulkheads somehow, despite all our precautions, crept up by about 1/8 of an inch during the dry fit. This is not a big deal but it opened up the gap between the chinelog and bulkhead cutout making it look bad. Because of the wedge shape of the bulkheads they really want to move up. We repositioned the misbehaving bulkheads and screwed them back in place using new screw holes. To epoxy everything together we started at the stem and removed the stem then each bulkhead, one at a time, smeared it with thickened epoxy then slid and screwed it back in place. I was worried that this would be a nightmare with the hull sides spronging apart while I'm trying to drive screws into place with the screw gun slipping out of my epoxy coated hands. It turned out much less traumatic than that. Removing any one bulkhead does not cause the hull sides to move significantly and when they did, like at the transom, the ratchet straps prevented significant springback.
Hull blocked up off the floor, ready for epoxy.
Still have a couple ratchet straps from chine to chine to keep the hull sides from springing back too far when each bulkhead is removed for epoxy application. This was not absolutely necessary but I was worried that some of the screws would strip out going back into the same holes in the soft cedar
My theory that a lot of the stress at the stem is relieved once all of the bulkheads are in place is proven by this picture. I was pleasantly surprised that the hull sides did not spring far apart once the screws were removed. In the picture above, the red clamp is holding the gunwhales from spreading further but there is very little tension on it. The bottom of the stem is completely unclamped! The two blue clamps are just holding the gunwhales to the hull sides.
Today Clamp Girl became Epoxy Vixen and helped tremendously by taping, mixing, squozing and generally getting into the thick of the assembly.
The hull sides wanted to spring apart a bit too much for my liking, once the transom was unscrewed so we used two ratchet straps, top and bottom to keep things under control.
Today, the hull got dry fitted in preparation for final assembly. It was lots of fun seeing it take shape for the first time. Kristi, my wife, spent most of the day acting as clamp girl which was a huge help. The last thing I had to do before the assembly was to cut chinelog clearance notches in the bulkheads. This was a bitchy little job as the angles get a bit crazy. The cuts are not perfect but an epoxy fillet will hide the sins. I used an offcut from the chinelog as a template for the cuts. Since the bulkhead sides are bevelled the cut has to follow that bevel.
Using chinelog offcut to mark bulkhead.
Clamp Girl preparing to fit stem.
We found it much easier to attach the hull sides to the stem with the hull sides spread apart to the stem angle. Had to move outside to get the room.
Stem screwed on and bulkheads ready to go.
First bulkhead is in. It required considerable force to curve the hull sides around it. We first screwed the bulkhead to one hull side then brought the hull sides together by using a ratchet strap from chine to chine. We clamped a clamp to each chine and then attached the ratchet strap hook to each clamp. This worked extremely well and allowed the hull sides to be slowly brought together with little drama except for some scary creaking sounds from the stem. Some folks reported having trouble with the hull sides cracking a bit just aft of the stem during this procedure so we left two clamps around the base of the stem to help the screws hold things together. We got a small crack in the first two inches of one chinelog but it closed back up once the rest of the bulkheads were installed. A bit of epoxy will take care of that.
Screwing bulkheads in.
You can see the clamps and ratchet strap used to pull the hull sides around the second bulkhead.
The bulkhead bevels specified in the plans are dead on perfect. I have to touch up one bevel but otherwise they all fit great.
It is amazing to watch the flat ply take on such a graceful curve once persuaded around the bulkheads.
We ran out of daylight but the dry fit is complete.
Transom required the clamp and ratchet strap treatment.
It never ceases to amaze me how something always takes 4x the time I estimate. You would think I'd learn by now... I was hoping to get the chine logs glued to the hull sides, cut all of the bulkhead chine log clearance notches and maybe do a dry fit of the hull. Yeah right. I got the chine logs shaped and glued on, thats it. But it's progress.
I bevelled the top of each chine log so that the joint between it and the hull side will not collect crud, besides I think this will look cool. The mandatory 3 coats of epoxy were added and then a light sanding to level bumps etc.
The chine log is glued to the hull side with 10mm overhang which is later planed down to a bevel. A line drawn 10mm from bottom of the chine log will serve as a guide when attaching to hull side.
Chine log being dry fitted with wood screws and ply anti-crush pads. This is a perfect example of why things always take longer than anticipated. I had forgotten that I need a kryllion of these ply pads so had to stop and cut them, then wrap each one in packing tape to prevent them from becoming a permanent part of the boat. The screws are removed after the epoxy cures and the holes are then filled. Since the outside of the hull is painted no evidence of the holes will show on the finished boat.
It's been a while but I'm slowly getting back to building. I was pretty close to hull assembly stage when the build got put on hold so it won't be long before we go 3D. I just got done scarfing the chine logs and shaping the stem. The plan for this weekend is to glue the chine logs to the hull sides and cut the chine log clearance notches in the bulkheads. Hoping to do a dry assembly run real soon. I'm so out of practice blogging that I forgot to take any pictures. Instead here is a video (it's in HD) from last weekend's 3 day sail trip to Cayo Costa with the WCTSS.
And the picture album from the same trip. Click on the slide show to see it big in Picasa.
The bulkheads and side panels are almost ready for assembly. Everything has 3 coats of epoxy and I spent a lot of time sanding all visible surfaces to a nice uniform flat finish. I'm hoping the effort to do it now will pay off by not having to sand a lot at awkward angles once the boat is assembled. I think I have this epoxy coating down. It takes a bit of practice to lay down thin and unifiorm coats. Working at above 70F makes for a much nicer surface due to the epoxy flowing more easily. Normally that's not a problem here in FL but, as I have complained before, this winter we have only had a handful of days even close to 70 so some of the panels needed a bit more sanding. This one turned out well, almost a shame to sand it.
Looks like this once sanded, the final coat of varnish will bring back the shine.
The hull assembly has given some folks a bit of trouble when it comes to aligning the bulkheads with the hull side panel bottom edges. The alignment is difficult once the chine logs have been glued on. So I decided to mark and drill the side panels and bulkheads before the side panels are glued together. Panel marked with bulkhead locations.
Temporary screw holes drilled.
I aligned the bulkheads and used the pre-drilled holes in the side panels as guides to drill the bulkheads.
Now when the time comes to assemble the hull all I have to do is line up the drilled holes and everything should go together correctly. The curved and beveled sides of bulkheads 1 and 2 were impossible to clamp in place for drilling so I just drilled one locating hole per side.
Once marked and drilled the side panels got glued together with a splice. The ply has a bit of curve to it and it's amazing how much weight it took to get the ends to lie reasonably flat.